WO2012019484A1

WO2012019484A1 - Control method and system for regulating voltage of power supply

Info

Publication number: WO2012019484A1
Application number: PCT/CN2011/075896
Authority: WO
Inventors: 王迪; 熊勇
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-08-09
Filing date: 2011-06-17
Publication date: 2012-02-16
Also published as: CN101908827A; CN101908827B

Abstract

A control method and system for regulating the voltage of a power supply. The method includes the following steps: defining an input state set and an output state set; defining pulse width modulation (PWM) fuzzy control rules, wherein the control result corresponding to the output state is obtained by the control rules according to the corresponding relationship between various combinations of the input states and various output states; regulating the voltage of the power supply according to the control result. By determining inputs, fuzzification and defuzzification, the response speed of the PWM voltage-regulating system in battery management is increased, the battery management function is optimized, and the output dynamic performance is improved.

Description

Control method and system for power supply voltage regulation

The invention belongs to the technical field of communication power sources, and particularly relates to a control method and system for power supply voltage regulation. Background technique

In today's era, information technology and communication technology are developing rapidly, the coverage of communication networks is becoming wider and wider, and a large number of communication base stations are being put into construction. The demand for communication equipment by major telecommunications and mobile communication operators is increasing, and it is necessary as a communication equipment. The indispensable power supply communication power supply equipment has also greatly increased its demand. In such a market context, it is important to improve the performance of existing communication portfolio power supplies. Battery management has become a very important module in combined power monitoring systems due to the battery life of the combined power supply. Pulse Width Modulation (PWM) voltage regulation system is an important part of battery management, and its performance optimization is important for improving system performance.

In the current combined power monitoring system using PWM voltage regulation, an incremental closed-loop control system is commonly used. Compared with the current limiting mode of the smart rectifier, the PWM method is simple and reliable, and it is not prone to unexpected errors (such as rectifier failure, communication interruption, large load transients, etc.); the biggest shortcoming is that the control response is very slow. If the user adjusts the battery charging voltage range to a large value, the PWM method may take several minutes to adjust the rectifier output to the rated voltage point. This is also a congenital deficiency of the closed-loop control system. For a faster response, it is likely to pay the price of system oscillations.

In the digital control system that is suitable for use, in addition to the closed-loop control system, there are proportional differential integration controllers (PCR, Proportion Integration Differentiation) and fuzzy control algorithms. For HD control, due to the large difference in the combined power supply application environment, the configured rectifier, electricity The differences between the types of pool groups are also large. The PID controller parameters determined by the experimental method are very limited and cannot be widely applied. The fuzzy control algorithm needs to have a deep understanding of the behavior of the designed control object. Due to the complexity and high reliability requirements of the communication power supply, the design difficulty is quite large. Therefore, there is no successful attempt in the communication power supply. And application. Summary of the invention

The main technical problem to be solved by the present invention is to provide a control method and system for power supply voltage regulation, optimize battery management functions, and improve output dynamic performance.

In order to solve the above technical problem, the present invention provides a control method for power supply voltage regulation, including the steps:

Defining an input state set and an output state set, defining a PWM fuzzy control rule, wherein the PWM fuzzy control rule obtains a control result corresponding to the output state according to a correspondence between different combinations of input states and different output states; and performing power according to the PWM fuzzy control rule Control of voltage regulation.

Further, the input state set includes a voltage deviation state set, a voltage change state set, and a current deviation state set.

Further, the voltage deviation state set includes the following state members: the output voltage is too low, the output voltage is low, the output voltage is just right, the output voltage is high, and the output voltage is too high; the voltage change state set includes the following state members: output voltage drop Too fast, the output voltage drops, the output voltage remains the same, the output voltage rises, and the output voltage rises too fast; the current deviation state set includes the following state members: battery current is too low, battery current is low, battery current is just right, battery current High, battery current is too high.

Further, in the voltage deviation state set, the interval value in which the state member is the output voltage is suitable, and the voltage deviation is within -0.3V~0.3V; the state member is the interval value in which the output voltage is high, including the voltage deviation in the - 1V 0V or less; the state member is the interval value of the output voltage is low, including the voltage deviation within 0V~1V; the state member is the interval value package whose output voltage is too high The voltage deviation is outside -0.5V; the interval value of the state member that the output voltage is too low includes the voltage deviation being outside 0.5V.

Further, in the voltage change state set, the interval value of the state member that the output voltage remains unchanged includes a voltage change rate between -0.1V and 0.1V; and the state member is an interval value of the output voltage rise. Including the voltage change rate is between -0.4V and 0V; the state member is that the voltage rises too fast, the interval value includes the voltage change rate is less than -0.3V; the state member is the voltage drop interval value including the voltage change The rate is between 0V and 0.4V; the state member is that the interval in which the voltage drops too fast includes the rate of change of the voltage greater than 0.3V.

In the current deviation state set, the interval value of the state member being the battery current is suitable, and the deviation of the battery charging current is within 90%-10%; the state member is the interval value of the battery current including the battery charging current. The deviation is between 100% and 140%; the interval value of the state member that the battery current is too high includes the battery charging current deviation greater than 120%; the state member is the battery current low interval value including the battery charging current deviation Between 60% and 100%; the state member is that the battery current is too low in the interval value including the battery charging current deviation is less than 80%.

Further, the set of output states includes the following output states: the output voltage should drop a lot, the output voltage should decrease, the output voltage should be maintained, the output voltage should rise, and the output voltage should rise a lot.

Preferably, the PWM fuzzy control rule obtains a control result corresponding to the output state according to a corresponding relationship between different combinations of input states and different output states, and specifically includes at least one of the following: the input state combination is: the battery current is too high, and the output The voltage drops too fast, and the corresponding output state is: The output voltage should be maintained;

The input state combination is: the battery current is too high, and the output voltage drops too fast, other voltage changes state, the corresponding output state is: the output voltage should drop a lot;

The input state combination is: the battery current is high, and the output voltage drops or the output voltage drops too fast, and the corresponding output state is: The output voltage should be maintained; The input state is combined as follows: The battery current is high, and the output voltage remains unchanged or the output voltage rises. The corresponding output state is: The output voltage should be reduced;

The input state is combined as follows: The battery current is just right, and the output voltage is too low or the output voltage is low or the output voltage is just right. The corresponding output state is: The output voltage should be maintained;

The input state combination is: The battery current is just right, and the output voltage is high, and the corresponding output state is: The output voltage should be reduced;

The input state combination is: The battery current is just right, and the output voltage is too high, the corresponding output state is: The output voltage should drop ^^;

The input state combination is: battery current is low, and the output voltage is too low or the output voltage is 氐, the corresponding output state is: The output voltage should be raised;

The input state is combined as follows: The battery current is low, and the output voltage is just right. The corresponding output state is: The output voltage should be maintained;

The input state combination is: The battery current is low, and the output voltage is high, and the corresponding output state is: The output voltage should be lowered;

The input state is combined as follows: The battery current is low, and the output voltage is too high, and the corresponding output state is: The output voltage should drop by more than 4 ;;

The input state is combined as follows: The battery current is too low, and the output voltage is too high. The corresponding output state is: The output voltage should rise a lot;

The input state combination is: The battery current is too low, and the output voltage is low, and the corresponding output state is: The output voltage should be raised;

The input state is combined as follows: The battery current is too low, and the output voltage is just right. The corresponding output state is: The output voltage should be maintained;

The input state combination is: The battery current is too high, and the output voltage is high, and the corresponding output state is: The output voltage should be lowered;

The input state combination is: Battery current is too low, and the output voltage is too high, corresponding to the output state To: The output voltage should drop a lot.

A control system for power supply voltage regulation, comprising a monitoring unit, a PWM fuzzy control unit and a rectifier, wherein:

The monitoring unit is used to detect the actual output voltage of the rectifier and the actual charging current of the battery. The PWM fuzzy control unit defines an input state set and an output state set, defines a PWM fuzzy control rule, and then according to the monitoring result of the monitoring unit, according to different combinations of input states Corresponding relationship with different output states obtains a control result corresponding to the output state, and performs control adjustment of the power supply voltage of the rectifier according to the control result of the output state.

Further, the input state set defined by the PWM fuzzy control unit includes a voltage deviation state set, a voltage change state set, and a current deviation state set.

Further, the set of voltage deviation states defined by the PWM fuzzy control unit includes the following state members: the output voltage is too low, the output voltage is low, the output voltage is just right, the output voltage is high, and the output voltage is too high; the PWM fuzzy control unit defines The set of voltage change states includes the following state members: the output voltage drops too fast, the output voltage drops, the output voltage remains unchanged, the output voltage rises, and the output voltage rises too fast; the set of current deviation states defined by the PWM fuzzy control unit includes the following states Members: Battery current is too low, battery current is low, battery current is just right, battery current is high, and battery current is high.

Further, the set of output states defined by the PWM fuzzy control unit includes the following output states: the output voltage should drop more, the output voltage should decrease, the output voltage should be maintained, the output voltage should rise, and the output voltage should rise a lot.

The input state combination is: Battery current is too high, and the output voltage drops too fast The voltage change state, the corresponding output state is: The output voltage should drop a lot; The input state combination is: The battery current is high, and the output voltage drops or the output voltage drops too fast, and the corresponding output state is: The output voltage should be maintained;

The input state is combined as follows: The battery current is high, and the output voltage remains unchanged or the output voltage rises. The corresponding output state is: The output voltage should be reduced;

The input state combination is: The battery current is just right, and the output voltage is too high, the corresponding output state is: The output voltage should drop ^ L more;

The input state combination is: The battery current is too low, and the output voltage is too low, the corresponding output state is: The output voltage should rise a lot;

The input state is combined as follows: The battery current is too low, and the output voltage is just right. The corresponding output state is: The output voltage should be maintained; The input state combination is: The battery current is too high, and the output voltage is high, and the corresponding output state is: The output voltage should be lowered;

The input state combination is: The battery current is too low, and the output voltage is too high, the corresponding output state is: The output voltage should drop a lot;

The input state combination is: The battery current is too low, and the output voltage is too high. The corresponding output state is: The output voltage should drop a lot.

The beneficial effects of the present invention are as follows: Compared with the prior art, the present invention obtains a fuzzy output by determining an accurate input state member, and blurring; finally, transforming the fuzzy output set into an accurate output by using a certain defuzzification rule, using fuzzy control Logic accelerates the response speed of the PWM voltage regulation system in battery management, optimizes battery management functions, and improves output dynamic performance. DRAWINGS

1 is a flowchart of a method for controlling power supply voltage regulation according to an embodiment of the present invention; FIG. 2 is a fuzzy curve of a voltage deviation EV according to an embodiment of the present invention;

3 is a fuzzy curve of a voltage variation error DV according to an embodiment of the present invention; FIG. 4 is a fuzzy curve of a current deviation EC according to an embodiment of the present invention;

FIG. 5 is a block diagram of a control system for power supply voltage regulation according to an embodiment of the present invention. detailed description

The present invention will be further described in detail below with reference to the accompanying drawings.

The invention is applied in a communication power system, utilizes fuzzy control logic, accelerates the response speed of the PWM voltage regulation system in the battery management, optimizes the battery management function, and improves the output dynamic performance as follows: selecting the reality related to the PWM voltage regulation in the power supply system The physical state variables, in the power monitoring, accurately monitor these signals, and compare with the target state, determine the precise input members, fuzzy, and obtain the fuzzy output; finally, through a certain solution fuzzy rule, convert the fuzzy output set into Accurate output. In order to facilitate the understanding of the PWM voltage regulation fuzzy control discussed later, firstly, the method of closed-loop voltage regulation and current limiting currently used is explained:

The monitoring unit detects the actual output voltage of the rectifier and the actual charging current of the battery.

When the battery is not charged with a large current, if the actual output voltage of the rectifier is equal to the specified charging voltage (generally in the range [target voltage -0.05, target voltage +0.09]), no adjustment is needed; if the output voltage is higher than the target voltage , the output must be lowered, that is, the voltage is adjusted downward according to the error range between the output voltage and the target voltage, and the output voltage is lower than the target voltage, and the output is adjusted in a stable step of 0.1V 0.2V. .

When the actual charging current of the battery is too large, the output voltage is unconditionally adjusted downwards, and the logic of the current limiting voltage regulation is performed to ensure that the battery is neither overcharged nor undercharged, and generally the battery charging current is maintained near the set current limit value. (90%~110%). The current limit target value of the battery is calculated from the battery capacity X charge current ratio. If the battery is charged with excessive current, the voltage is reduced by a large step (0.5V); if the battery is charged with a large current, the voltage is lowered in a smaller step (0.1~0.3V). If all the batteries have a small charging current or a small current discharge, the output voltage is raised, and the step size is generally 0.1~0.3V.

Specific embodiments of the present invention are described in detail below.

Assume that a combined power system has components such as AC input, AC-DC converter, DC output, battery, and monitoring unit. Among them, the monitoring unit can accurately and real-time detect the voltage of the DC output, the charging current of the battery; and adjust the voltage of the rectifier through the PWM method to control the charging voltage of the battery and limit the charging current.

Referring to FIG. 1 , FIG. 1 is a flowchart of a PWM voltage modulation fuzzy control method, which includes the following steps:

S101. Select a suitable PWM voltage-regulated real state variable according to the configuration and performance of the communication combined power system. In this embodiment, three physical quantities of “voltage deviation”, “voltage deviation variation”, and “current deviation” are selected as fuzzy controllers. Accurate input variable fuzzy set, select "duty cycle change" Then the fuzzy set of the precise output variables of this fuzzy controller. The main control target of the PWM voltage regulation system is the output voltage, and the final control purpose is the charging current of the battery. Therefore, the function of the control system also determines the selection of the input state variable to a certain extent.

S102. Perform effective and reliable detection on the selected state variables. The power monitoring unit requires a high level of accuracy in the output voltage and battery charging current. On the hardware, the detection circuit can use components with high precision and good stability, and cooperate with the software to de-scramble using algorithms such as digital filtering, so that the detection accuracy of the voltage can reach 0.5% and the error is ±0.1V. The accuracy of the battery current Up to 1%, error ± 0.1A. On the other hand, from a real-time perspective, the monitoring unit periodically detects the output voltage and the battery current in two hundred milliseconds; the output voltage is periodically adjusted every second. Therefore, from the perspective of data reliability and timeliness, the output voltage and battery current are also suitable as input variables for the control system.

S103. Divide a state member of the input and output fuzzy set of the PWM voltage regulation fuzzy control system according to performance requirements such as output voltage regulation of the communication power source and battery charge management, and determine a corresponding input member set according to the detected physical quantity value. status.

In this embodiment, the system performs the division of the fuzzy system input and output variable member sets, as follows:

1) Define four precise input physical quantities:

VOL — TARGET target output voltage

VOL OUT actual output voltage (measured voltage)

CUR LIMITED current limit

CUR_OUT Actual charging current (measuring current)

2) Define a precise output physical quantity:

N duty cycle data value

3) Define three precise control inputs:

EV = VOL— TARGET - VOL OUT voltage deviation (difference between target output voltage and actual output voltage) DV= VOL— OUT ( N ) - VOL OUT ( Nl ) Voltage change

EC = CUR- LIMITED - CUR- OUT Current deviation (the difference between the current limit and the actual charge)

4) Define a precise control output:

Ν Ν = Ν + 占空比 duty cycle change t

This embodiment defines the state of the following input member sets:

1) Voltage deviation EV:

EV L output voltage is too high

EVNS output voltage 4氐

EVZE output voltage is just right

EVPS output voltage is high

EVPL output voltage is too high

2) Voltage change 4匕 DV:

DVNL output voltage drops too fast

DVNS output voltage drop

DVZE output voltage remains unchanged

DVPS output voltage rises

DVPL output voltage rises too fast

3) Current deviation EC:

ECNL battery current is too high

ECNS battery current is low

ECZE battery current is just right

ECPS battery current is high

ECPL battery current is too high

At the same time, the following states of the precise output state member set are defined: 1) Output variables:

The ONL output voltage should be lower

The ONS output voltage should drop 4氐

OZE output voltage should be maintained

OPS output voltage should rise

OPL output voltage should rise a lot

Among them, the value range of the status member is absolute FALSE to absolute TRUE. Since the monitoring system uses the microcontroller to control the PWM voltage regulation, the output register is one byte, so the value range of each fuzzy state member is defined from absolute TRUE (255) to absolute FALSE (0).

S104: Quantify each state member of the divided fuzzy set, and give a fuzzy curve of the error, and obtain a corresponding quantized value according to the state member value of the input variable, and the fuzzy quantization curve.

For convenience of calculation, the present invention multiplies voltage error, battery current error, voltage variation, etc. by 10 times and then rounds up. The following is introduced separately.

For the voltage error, the output voltage deviation is within ±0.1V, and the error is 0, which satisfies the accuracy requirements of the present invention for the output voltage. The voltage deviation EV blur curve is shown in Figure 2. The error is within ±3 (±0.3V), which means EVZE; within ±10, it means EVPS or EVNS; outside of ±5, it means EVPL or EVNL. Of course, these thresholds are all adjustable.

As shown in Figure 3, the voltage change is the amount of change in output voltage per second. If the rate of change of voltage is within ±1 (-0.1V~0.1V), the error is considered to be 0, indicating DVZE; within -4 to 0 (-0.4V-0V), the voltage is considered to rise, indicating DVPS. When it is -0.2V, the value is 255; if it is less than -2 ( <-0.2V), the voltage rise is considered too fast, indicating DVPL. When the value is less than -0.5V, the value is 255; within 0~4 (0V~0.4V), the voltage is considered to decrease, indicating DVNS. When it is 0.2V, the value is 255; if it is greater than 2 O0.2V), the voltage drop is considered too fast, indicating DVNL. When it is greater than 0.5V, the value is 255; these thresholds are also adjustable. As shown in Figure 4, if the battery charging current deviation is within ±1 (90%~110%), the error is 0; within -4~0 (100%~140%), the battery current is considered high, indicating ECPS , when -2 ( 120% ), the value is 255; less than -2 ( >120%), the battery current is considered too high, indicating ECPL, less than -5 (>150%), the value is 255; at 0~ Within 4 (60%~100%), the battery current is considered low, indicating ECNS, when 2 (80%), the value is 255; if it is greater than 2 (<80%), the battery current is too low, indicating ECNL, greater than 5 (<50%), the value is 255. Of course, these thresholds can be adjusted according to the actual situation.

S105. Develop a control rule of the PWM voltage regulation fuzzy controller, and obtain a state member of the output variable according to the control rule.

The PWM voltage regulation fuzzy rule established in this embodiment is as follows:

If ECPL and DVNL then OZE

If the battery current is too high but the output voltage drops too fast, the output voltage should be maintained; if ECPL and ( DVNS or DVZE or DVPS or DVPL ) then ONL If the battery current is too high, but the output voltage does not drop quickly (output voltage drops too The output voltage should drop a lot;

If ECPS and ( DVNL or DVNS ) then OZE

If the battery current is high, but the output voltage drops or falls too fast, the output voltage should be maintained;

If ECPS and ( DVZE or DVPS or DVPL ) then ONS

If the battery current is high, but the output voltage remains the same or rises, the output voltage should be reduced;

If ECZE and ( EVNL or EVNS or EVZE ) then OZE

If the battery current is just right and the output voltage is too low / low / just right, the output voltage should be maintained;

If ECZE and ( EVPS ) then ONS

If the battery current is just right and the output voltage is high, the output voltage should be reduced; If ECZE and ( EVPL ) then ONL

If the battery current is just right and the output voltage is too high, the output voltage should drop by more than ;; if ECNS and ( EVNL or EVNS ) then OPS

If the battery current is low and the output voltage is too low/low, the output voltage should rise; if ECNS and ( EVZE ) then OZE

If the battery current is low and the output voltage is just right, the output voltage should be maintained; if ECNS and ( EVPS ) then ONS

If the battery current is low and the output voltage is high, the output voltage should be reduced;

If ECNS and ( EVPL ) then ONL

If the battery current is low and the output voltage is too high, the output voltage should drop ^^; if ECNL and EVNL then OPL

If the battery current is too low and the output voltage is too low, the output voltage should rise a lot; if ECNL and EVNS then OPS

If the battery current is too low and the output voltage is 氐, the output voltage should rise;

If ECNS and ( EVZE ) then OZE

If the battery current is too low and the output voltage is just right, the output voltage should be maintained; if ECNS and ( EVPS ) then ONS

If the battery current is too low and the output voltage is high, the output voltage should be reduced;

If ECNS and ( EVPL ) then ONL

If the battery current is too low and the output voltage is too high, the output voltage should drop by ^^.

Regarding the PWM fuzzy control rule, in the present embodiment, when designing the control rule, the PWM closed-loop voltage regulation logic is largely followed. The fundamental purpose of the monitoring unit to control the output voltage is to limit the battery charging current, and then adjust the output voltage appropriately after controlling the battery charging current.

Here are a few typical examples for analysis:

1) If the battery current is large but the output voltage drops too fast, indicating that the current rectifier has hardware limit current, at this time: PWM adjustment does not make much sense, so keep the current voltage; 2) If the battery current is large but the voltage does not drop quickly, in order to protect the battery from overcharging, the output voltage should be drastically reduced immediately, and the voltage difference between the rectifier and the battery should be reduced, thereby reducing the battery current and achieving the purpose of current limiting. ;

3) When the battery current is just right, the output voltage is relatively low, indicating that the system has reduced the output voltage to achieve control of the battery current, then the output voltage must be controlled and cannot be increased; otherwise, if the battery current is appropriate When the output voltage is higher than the target voltage, the output voltage needs to be reduced to the target voltage at this time, without having to consider that the battery charging current is reduced;

4) When the battery current is low, if the output voltage is lower than the target value, increase the output voltage while observing the battery current. If the battery is still not overcharged when it rises to the target voltage, the output can be stabilized at the target voltage. If the battery has overcharged during the voltage regulation, stop the voltage regulation to stabilize the charging current. Of course, if the output voltage is higher than the target value, you don't have to worry about overcharging of the battery. Just lower the output voltage to the target value.

S106, defuzzification process. By dequantifying the weighted average calculation, an accurate N output can be obtained. The weight coefficient selected here will be adjusted according to the control effect, mainly based on the combined power output performance and battery management characteristics, combined with PWM voltage limiting current limiting logic, so that the control effect develops in the expected direction.

It should be noted that the control of the PWM duty ratio of the output voltage adjustment 1N must be limited to a certain range, such as (-TN, +TN). When ONL is absolute TRUE (255), it is -30 (the corresponding output voltage is lowered by 0.5V); when ONS is absolute TRUE (255), the corresponding N is -6 (the corresponding output voltage is lowered by 0.1V). When OPL is absolute TRUE (255), it is 30 (corresponding output voltage is increased by 0.5V); when OPS is absolute TRUE (255), the corresponding N is -6 (corresponding output voltage is increased by 0.1 V).

When deblurring, the weighting coefficient is adjusted in real time to achieve the purpose of adjusting the output PWM control signal, thereby accelerating the adjustment speed of the output voltage in the case of stabilizing the system output.

The following examples illustrate the power to illustrate: If the battery current is large, but the voltage does not drop quickly, in order to prevent the battery from overcharging, the output voltage needs to be greatly reduced. According to this control rule, the fuzzy output ONL is obtained. The invention firstly gives a higher weight coefficient of "battery current", and gives a lower weight coefficient of "the voltage does not drop very quickly". When ONL is absolute TRUE (255), it is - 30, and the corresponding output voltage is Down 0.5V. After the down adjustment is completed, observe the output of the system again. If the battery current is still large, the fuzzy controller continues to output ONL and continues to reduce the output voltage by 0.5V. After adjusting several times, there will be a case where the battery current is large and the output voltage is low, or the battery current is just right and the output voltage is low. At this time, the stable battery current still has a relatively heavy weight coefficient. After charging for a certain period of time, the discharge voltage will rise as the battery voltage rises, and the battery charge current will decrease. At this time, the output performance of the system will be improved—that is, increasing the output voltage will have a heavier weight coefficient, and the battery is charged. The weight of the current control will decrease, and the fuzzy controller will execute the control rule of "If the battery current is low and the output voltage is low, the output voltage should rise" or "If the battery current is just right and the output voltage is low, keep the current voltage".

The following describes the PWM mode voltage regulation fuzzy control process described above.

Mainly for the normal charging of battery current and high current charging.

When the actual application is applied, the configuration of a DC communication power system is as follows: Battery capacity 300Ah, 6 rectifiers, load output 30A. In addition, the charging current ratio is 0.15C, the equalizing voltage is set to 56.4V, the float voltage is 53.5V, and the battery voltage is 50V. Battery charge current limit value is calculated as:

Current limit value = total battery capacity X charge current ratio

Regardless of the temperature compensation of the battery charging current, the battery current limit is 300 χ 0.15 = 45 Α. When the system has a power outage, the battery supplies power to the load, and then the power supply is restored. At this time, assuming that the battery voltage is 46V, the rectifier voltage starts to adjust from 45.0V to the average charging voltage of 56.4V:

Initially, when the rectifier voltage is lower than 46V of the battery voltage, the battery will not be charged. The pool is still in a discharged state, and the input fuzzy state is ECNL and EV L. At this time, the output should be OPL, that is, the driving output voltage rises rapidly, and the step of voltage rise is 0.5V. At this point, the fuzzy input that determines the output of the system is the battery current error and voltage error.

When the output voltage rises above 46V, the rectifier starts to charge the battery, and gradually takes over the load. The discharge current of the battery gradually decreases and begins to transition to charging. At this time, the input fuzzy state is still ECNL and EVNL, and the output is also Still OPL, the drive output voltage rises rapidly, and the step of voltage rise is 0.5V. At this point, it is determined that the fuzzy input of the system output is still the battery current error and the voltage error.

Observe the output voltage. When it rises to about 50V, the battery starts to have charging current. At the beginning, the charging current is very small. The input fuzzy state is ECNS and EVNL. At this time, the output should be OPS, and the rate of voltage rise will be relatively slow, up. The step size is 0.2V.

When the output voltage continues to rise and the target voltage is approaching, the battery's charging current will be larger. If the fuzzy state of the charging current reaches ECZE, the fuzzy state of the voltage is EVNS or EVZE. At this time, the output is OZE, and the current voltage is maintained, and the charging is advanced. If the voltage regulation performance of the rectifier is not good, the charging current may be possible. The ECPS will appear for a short time. At this time, the input state of the voltage is EVZE or EVPS. In this case, the battery charging current needs to be reduced, and the ONS is output, and the ONS is adjusted down by 0.1V steps until the current fuzzy state reaches ECZE, and the output is OZE.

If the battery is charged to a certain extent, the charging current will decrease until the fuzzy state of the charging current reaches ECNS. At this time, the output voltage is either EVNS or EVZE, then the output is OPS or OZE: If the output voltage does not reach the target voltage, It is slowly adjusted upwards at 0.1V until the target voltage is reached. If the output voltage has reached the target voltage, the output voltage is no longer adjusted, so that the output voltage can be stabilized at the target value.

The above is a typical example of the current-limit voltage regulation fuzzy control logic during the battery charge and discharge current change when the power is turned off to the incoming call. The state of charge of the battery is from ECNL to ECNS, then to ECZE (may experience a brief ECPS state, mainly depending on the regulator's voltage regulation performance), according to the electricity The change in the current of the cell adjusts the output voltage until the output is stable and the charge current limit is achieved. The ECPL situation does not generally occur. When the system is powered off, the battery is discharged to a certain extent, causing the battery to be removed from the system. When the system power is restored, the battery will be reconnected to the system through the DC contactor. At this time, the battery may be charged at a high current. When ECPS or ECPL occurs, the adjustment of the output voltage is determined according to the error of the voltage: If the fuzzy state is DV L, it means that the rectifier cannot supply enough output, and the hardware has been down-regulated to maintain the output. Adjust and keep it; if the fuzzy state is DVNS, the software will continue to slightly lower the output voltage to reduce the battery charging current; if the fuzzy state is DVPS, DVPL or DVZE, the software needs to stop the upward voltage, the voltage will be large Decrease until the battery's charging current reaches ECZE, and then gradually bring the output voltage closer to the target value.

According to the method described above, the embodiment further discloses a control system for power supply voltage regulation. As shown in FIG. 5, the monitoring unit 501 includes a PWM fuzzy control unit 502 and a rectifier 503, wherein:

The monitoring unit 501 is configured to detect the actual output voltage of the rectifier 503 and the actual charging current of the battery. The PWM fuzzy control unit 502 defines an input state set and an output state set, and then quantizes the input and output states, defines a PWM fuzzy control rule, and then according to The monitoring result of the monitoring unit 501 controls the adjustment of the power supply voltage of the rectifier 503 in accordance with the PWM fuzzy control rule.

The input state set defined by the P WM fuzzy control unit 502 includes a voltage deviation state set, a voltage deviation change state set, and a current deviation state set.

The set of voltage deviation states defined by the PWM fuzzy control unit 502 includes that the output voltage is too low, the output voltage is low, the output voltage is just right, the output voltage is high, and the output voltage is too high; the voltage deviation change state set defined by the PWM fuzzy control unit Including the output voltage drops too fast, the output voltage drops, the output voltage remains unchanged, the output voltage rises, and the output voltage rises too fast; the current deviation state set defined by the PWM fuzzy control unit includes the battery current is too low, the battery The current, the battery current is just right, the battery current is high, and the battery current is high.

The set of output states defined by the PWM fuzzy control unit 502 includes that the output voltage should drop a lot, the output voltage should decrease, the output voltage should be maintained, the output voltage should rise, and the output voltage should rise a lot.

The PWM fuzzy control rule defined by the PWM fuzzy control unit 502 includes at least one of the following:

The input state combination is: The battery current is too high, and the output voltage drops too fast, the corresponding output state is: The output voltage should be maintained;

The input state is combined as follows: The battery current is high, and the output voltage drops or the output voltage drops too fast. The corresponding output state is: The output voltage should be maintained;

The input state combination is: battery current is low, and the output voltage is too low or the output voltage is 4氐, the corresponding output state is: The output voltage should be raised;

The input state is combined as follows: the battery current is too high, and the output voltage is high, and the corresponding output state is: The output voltage should be lowered;

In summary, the embodiment of the present invention selects a real physical state variable related to PWM voltage regulation in a power supply system in an existing combined power supply monitoring system that is regulated by P WM mode. Accurate monitoring is performed, and compared with the target state, the members of the precise input are determined, and the fuzzy output is obtained, and the fuzzy output is obtained. Finally, the fuzzy output set is converted into the accurate output by a certain solution fuzzy rule. Improve battery management performance by optimizing the PWM voltage regulation system. By using fuzzy control logic, it not only ensures the stability of the system, but also speeds up the response speed of the PWM voltage regulation system in current battery management. It can optimize the battery management function, perform efficient battery management, and improve the dynamic performance of the output.

The above is a further detailed description of the present invention in connection with the specific embodiments, and the specific embodiments of the present invention are not limited to the description. It is to be understood by those skilled in the art that the present invention may be practiced without departing from the spirit and scope of the invention.

Claims

Claim

A control method for power supply voltage regulation, comprising the steps of: defining an input state set and an output state set, defining a pulse width modulation (PWM) fuzzy control rule, the PWM fuzzy control rule being different according to different combinations of input states The corresponding relationship with the different output states is obtained, and the control result corresponding to the output state is obtained; the control and adjustment of the power supply voltage is performed according to the PWM fuzzy control rule.

2. The method of claim 1 wherein the set of input states comprises a set of voltage deviation states, a set of voltage change states, and a set of current bias states.

3. The method according to claim 2, wherein the voltage deviation state set comprises the following state members: the output voltage is too low, the output voltage is low, the output voltage is just right, the output voltage is high, and the output voltage is too high;

The set of voltage change states includes the following state members: the output voltage drops too fast, the output voltage drops, the output voltage remains unchanged, the output voltage rises, and the output voltage rises too fast;

The current bias state set includes the following state members: battery current is too low, battery current is low, battery current is just right, battery current is high, and battery current is too high.

The method according to claim 3, wherein in the set of voltage deviation states, the interval value in which the state member is the output voltage is suitable, and the voltage deviation is within -0.3V~0.3V; The interval value of the output voltage is high, and the voltage deviation is within -1V~0V; the interval value of the state member being the output voltage is low, and the voltage deviation is within 0V~1V; the state member is the interval value of the output voltage being too high. Including the voltage deviation is outside -0.5 V; the state member is that the output voltage is too low for the interval value including the voltage deviation outside 0.5V.

The method according to claim 3, wherein in the set of voltage change states, the interval value of the state member that the output voltage remains unchanged includes a voltage change rate between -0.1V and 0.1V. The interval value of the state member for the output voltage rise includes a voltage change rate between -0.4V and 0V; the state member is that the voltage rises too fast, and the interval value includes the voltage The rate of change is less than -0.3 V; the interval value of the state member is the voltage drop including the voltage change rate between 0V and 0.4V; the state member is the interval where the voltage drops too fast, including the rate of change of the voltage greater than 0.3 V.

The method according to claim 3, wherein in the current deviation state set, the interval value of the state member that the battery current is just right includes the deviation of the battery charging current within 90% to 110%; The value of the interval in which the battery current is high includes the deviation of the battery charging current between 100% and 140%; the value of the state member that the battery current is too high includes the deviation of the charging current of the battery is greater than 120%; The interval value of the battery current is low, and the deviation of the battery charging current is between 60% and 100%; the interval value of the state member that the battery current is too low includes the deviation of the battery charging current being less than 80%.

7. The method of claim 1, wherein the set of output states comprises the following output states: the output voltage should drop by ^^. The output voltage should be lowered, the output voltage should be maintained, the output voltage should be raised, and the output The voltage should rise a lot.

The method according to any one of claims 1 to 4, wherein the PWM fuzzy control rule obtains a control result corresponding to the output state according to a corresponding relationship between different combinations of input states and different output states, specifically including At least one of the following:

The input state combination is: The battery current is just right, and the output voltage is too low or the output voltage Low or output voltage is just right, the corresponding output state is: The output voltage should be maintained;

The input state combination is: The battery current is just right, and the output voltage is too high, the corresponding output state is: The output voltage should drop a lot;

The input state combination is: The battery current is low, and the output voltage is high, and the corresponding output is: The output voltage should be lowered;

The input state combination is: The battery current is too low, and the output voltage is too 4 氐, the corresponding output state is: The output voltage should rise a lot;

9. A control system for power supply voltage regulation, comprising: a monitoring unit, a PWM fuzzy control unit, and a rectifier, wherein: The monitoring unit is used to detect the actual output voltage of the rectifier and the actual charging current of the battery.

The PWM fuzzy control unit defines an input state set and an output state set, defines a PWM fuzzy control rule, and then obtains a control result corresponding to the output state according to a monitoring result of the monitoring unit, according to a corresponding relationship between different combinations of input states and different output states, and The control of the power supply voltage of the rectifier is performed according to the control result of the output state.

10. The system of claim 9, wherein the set of input states defined by the PWM fuzzy control unit comprises a set of voltage deviation states, a set of voltage change states, and a set of current bias states.

11. The system according to claim 10, wherein the set of voltage deviation states defined by the PWM fuzzy control unit comprises the following state members: the output voltage is too low, the output voltage is low, the output voltage is just right, and the output voltage is high. The output voltage is too high;

The set of voltage change states defined by the PWM fuzzy control unit includes the following state members: the output voltage drops too fast, the output voltage drops, the output voltage remains unchanged, the output voltage rises, and the output voltage rises too fast;

The set of current deviation states defined by the PWM fuzzy control unit includes the following state members: battery current Tai, battery current, battery current is just right, battery current is high, and battery current is high.

12. The system of claim 9, wherein the set of output states defined by the PWM fuzzy control unit comprises the following output states: the output voltage should drop a lot, the output voltage should decrease, the output voltage should be maintained, and the output voltage should Raise, the output voltage should rise a lot.

The system according to any one of claims 9 to 12, wherein the PWM fuzzy control rule obtains a control result corresponding to the output state according to a correspondence between different combinations of input states and different output states, specifically including At least one of the following:

The input state combination is: The battery current is too high, and the output voltage drops too fast, corresponding output The status is: The output voltage should be maintained;

The input state is combined as follows: the battery current is low, and the output voltage is too low or the output voltage is ^ 氐, the corresponding output state is: The output voltage should be raised;

The input state combination is: The battery current is low, and the output voltage is high, corresponding to the output ^! The fire state is: The output voltage should be reduced;

The input state combination is: The battery current is low, and the output voltage is too high, and the corresponding output state is: The output voltage should drop too much;

The input state combination is: The battery current is too low, and the output voltage is low, and the corresponding output state is: The output voltage should be raised; The input state is combined as follows: The battery current is too low, and the output voltage is just right. The corresponding output state is: The output voltage should be maintained;

The input state combination is: The battery current is too low, and the output voltage is high, and the corresponding output state is: The output voltage should be lowered;

The input state combination is: The battery current is too low, and the output voltage is too high, corresponding to the 3⁄4 output state: The output voltage should drop a lot;