KR20120138145A - Intelligent cabinet-panel having energy managing function in the smart grid environment - Google Patents

Abstract

PURPOSE: An intelligent cabinet panel having an energy management function in smart grid environment is provided to prevent unnecessary power consumption by blocking exiting current unnecessarily consumed in a transformer of a power converter connected to a system. CONSTITUTION: A first power converter device(11) and a second power converter(19) are located in different power systems. A battery management system(21) controls charging and discharging in an energy storage(17). A breaker(101) blocks main wiring or a part of wiring according to the control of an energy management part(130). A first switch(103) is located between the breaker and the first power converter. A second switch(105) is located between the breaker and the second converter. [Reference numerals] (101) Breaker; (103) First switch; (105) Second switch; (107) Detector; (109) Display part; (11) First power converter device; (111) Input part; (113) Communication part; (13) Commercial AC power side; (130) Energy management part; (131) System controller; (133) Monitoring part; (135) Power calculator; (137) Exciting current controller; (15) Smart meter; (17) Energy storage; (19) Second power converter; (21) BMS; (23) Load; (25) Electricity safety monitoring device; (27) Energy management server; (29) Manager terminal; (AA) New and renewable energy device; (BB) Intelligent panel board

Description

Intelligent Cabinet-Panel Having Energy Managing Function in the Smart Grid Environment

The present invention relates to an intelligent distribution board having an energy management function in a smart grid environment.

Up to now, distribution boards have been recognized as electrical devices for distributing incoming power to each electric power station installed in a collective power source such as a building. Conventional distribution boards include a molded case circuit breaker (MCCB) connected to the power inlet side of the enclosure, and a plurality of branch breakers (wiring breakers, earth leakage breakers, etc.) or switches.

If leakage current or overcurrent occurs in any one or more branch circuits, the branch circuit breaker installed at the front end of the circuit detects the overcurrent or leakage current and trips the circuit, thereby disconnecting the fault line from the power supply. This prevents the failure of any one point from propagating to the other circuit side.

In recent years, the distribution panel, which has been developed and expanded in use, goes beyond this simple power distribution function to measure voltage and current, calculate the amount of power used, display through display devices, analyze power accidents by analyzing power waveforms, and communicate with remote sites. There is a tendency to digitize with various intelligent functions. As a prior art for such a digital distribution panel, reference may be made to Korean Patent Registration No. 0999999 (Invention: Digital Distribution Panel).

Renewable energy such as photovoltaic power generation is also transmitted to a power system through a distribution panel or charged to a storage device such as a rechargeable battery, and the charged energy is again supplied with power to various electronic devices or transmitted to the system.

On the other hand, Smart Grid is a technology that knows electricity consumption, supply amount, and power line status by fusion of information and communication technology in the power grid, which can maximize energy efficiency. The core of the smart grid is to integrate information and communication technologies such as Zigbee and power line communication into the power grid, allowing consumers and utilities to exchange information (eg, real-time electricity bills) in real time. Therefore, in addition to the energy supplied from the commercial AC power, general management is required for the smart grid era.

In addition, a power conditioning system (PCS) for converting power is provided on a grid connected from a commercial AC grid to an energy storage device or from a renewable energy device to an AC grid. Even when the transformer is not doing its job, it consumes unnecessary excitation current. New intelligent distribution boards must be able to block these unnecessary power consumptions.

Furthermore, the conventional distribution panel is designed in such a way that the amount of power in the branch circuit can not be measured other than the power in the main circuit breaker circuit due to product price or the like, but accurate power measurement is also required in each branch circuit.

An object of the present invention is to provide an intelligent distribution board having an energy management function in a smart grid environment.

Specifically, an object of the present invention is for grid linkage of a power conversion device for converting power of renewable energy or energy storage device for storage in an energy storage device (ESS) for the purpose of linkage with a commercial AC grid. It is to provide an intelligent distribution board that can reduce unnecessary power consumption in the transformer.

Another object of the present invention is to accurately analyze the power consumption of each branch circuit from the power information measured by the main circuit breaker and the current information measured by each branch breaker when the power is branched from the main circuit breaker to each branch breaker. To provide an intelligent distribution panel.

In order to achieve the above object, the intelligent distribution panel according to the present invention includes a blocking unit and a system control unit.

The cut-off unit includes a first power converter for connecting a renewable energy device to a grid or a second power converter for connecting an energy storage device to a grid, and a main wiring provided on a grid branched to a commercial AC power supply side and a load side. A breaker and a branch breaker are provided to branch the power on the grid.

The grid control unit controls the power conversion device in accordance with an electric charge provided from a smart meter connected to the commercial AC power supply, thereby charging the energy storage device to the energy storage device or stored in the energy storage device. Energy is discharged through the block.

For example, the grid controller may control the second power converter to charge the energy storage device with energy distributed through the blocking unit when the electric charge is low. On the contrary, when the electric charge is expensive, the system controller may control the second power converter so that the energy storage device charged in the energy storage device is discharged.

According to an embodiment, an intelligent distribution panel of the present invention may be provided between the first and second power converters and the cutoff unit, respectively, to control the switch unit and the first switch unit and the second switch unit to control the system. The excitation current control unit may further include.

Here, the excitation current control unit, when the first and the second power converter is in the idle state (for example, when there is no charge or discharge of the energy storage device through the second power converter), the first switch unit and By opening the second switch unit to turn off the system between the first and second power converters and the breaker, respectively, it is possible to block consumption of the excitation current in the first and second power converters.

According to another embodiment of the present disclosure, the intelligent distribution panel may include: a detector configured to measure current consumption for each branch in the blocking unit; A display unit for displaying the information so that the information can be visually recognized; And a power calculation unit configured to receive the quarterly current consumption from the detection unit, calculate a quarterly power consumption proportional to the quarterly current consumption based on the power consumption value of the main wiring, and display the same on the display unit. can do.

In addition, the detector may measure the leakage current of each branch in the blocking unit, and the power calculation unit uses the quarterly leakage current value measured by the detector to determine effective power consumption due to leakage in the branch. It may be calculated by the following equation and displayed on the display unit.

≪ Equation &

Active power consumption due to leakage = sensed effective leakage current × voltage

In addition, the power calculation unit may calculate the power consumption of each breaker in the breaker according to the following equation to display on the display.

≪ Equation &

Breaker Power Consumption = Voltage Drop × Current

Here, the voltage drop is a voltage difference between the input terminal and the output terminal of the circuit breaker.

Intelligent distribution panel according to the present invention provides a smart grid environment, in particular energy management function according to the electricity rate information provided in real time.

In addition, the intelligent distribution panel of the present invention can block the unnecessary power consumption by blocking the excitation current that can be unnecessarily consumed in the transformer of the power converter connected to the grid to store or reverse the energy of the power system in the energy storage device. have.

In addition, according to the present invention, by displaying the power consumption due to leakage current less than the rated breaking current to operate the earth leakage breaker consumed by the earth leakage through the intelligent distribution panel, it can provide a function to save power and safety.

In addition, according to the present invention, it is possible to provide a function of an intelligent home distribution panel that can additionally perform safety management by using measured values such as current, leakage current, voltage, and temperature from distributed power supplies measured through the intelligent distribution panel. There is an advantage.

1 is a view showing an energy management system having an intelligent distribution panel according to an embodiment of the present invention, and
2 is a block diagram of a power conversion apparatus according to an embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the drawings.

Referring to FIG. 1, the intelligent distribution panel 100 according to an embodiment of the present invention is connected to a power system including a renewable energy control device as well as a commercial AC power source to manage the overall energy.

The intelligent distribution panel 100 includes a first power conversion system (PCS) 11 provided on the renewable energy device side, a smart meter 15 provided on the commercial AC power supply side 13, The second power converter 19, the battery management system (BMS) 21, and other various loads 23 provided on the energy storage device 17 side are connected.

Here, the commercial AC power supply side 13 means a system of a commercial AC power supply, and is not necessarily limited to a power supply supplier, but includes a power importer, and loads 23 through an intelligent distribution panel 100. To power. The load 23 corresponds to a side that consumes electric power, such as a home appliance or an electric vehicle (EV) charger.

The smart meter 15 is an electronic electricity meter, which can be metered according to a smart grid environment, and can receive electricity rates in real time through two-way communication with a power company. The intelligent distribution board 100 can read the real-time electricity bill from the smart meter 15. In FIG. 1, the smart meter 15 is illustrated as being installed outside the intelligent distribution panel 100, but may be installed as an internal configuration of the intelligent distribution panel 100.

The first power converter 11 and the second power converter 19 are provided between different power systems and used to interconnect the systems. The renewable energy produced by the renewable energy device is converted into a form suitable for the system in the first power converter 11 and then transmitted to the energy storage device 17 or the load 23 through the intelligent distribution panel 100. .

In addition, the power distributed from the intelligent distribution panel 100 to the energy storage device 17 is converted into direct current by the second power converter 19 to be charged in the energy storage device 17, and to the energy storage device 17. The charged energy is converted into alternating current by the second power converter 19 and provided to the load 23 or other commercial AC power supply side 13. In addition to the example shown in FIG. 1, the power converters 11 and 19 may be provided anywhere on the system where the shape conversion of power is required.

The battery operating device 21 controls the charging or discharging of the energy storage device 17.

In addition, the intelligent distribution panel 100 may be connected to the electrical safety monitoring device 25 for monitoring the renewable energy device. The electrical safety monitoring device 25 monitors renewable energy devices, and when a fault condition occurs, the circuit can be disconnected from the power supply. Send to 100.

The intelligent distribution panel 100 includes a breaker 101, a first switch unit 103, a second switch unit 105, a detector 107, a display unit 109, an input unit 111, a communication unit 113, and an energy management unit. Including the 130, it is possible to perform intelligent energy management for the smart grid era beyond simple power distribution, and to comprehensively perform the blocking of unnecessary excitation currents and the monitoring of quarterly power consumption.

The breaker 101 distributes the power on the power system, including a main circuit breaker (MCCB) and a plurality of branch breakers (wiring breakers, earth leakage breakers, etc.) or switchgear. Shut off the system in case of leakage current. In addition, the blocking unit 101 may block the main wiring or some branch wiring if necessary under the control of the energy management unit 130.

The first switch unit 103 and the second switch unit 105 correspond to a relay switch or a semiconductor switch such as a transistor, and the like, and are switched under the control of the energy management unit 130 to cut off or connect the corresponding power system. do. The switch unit may be provided anywhere on the system, which is not limited to the first switch unit 103 and the second switch unit 105 shown in FIG. 1, and which needs to be regulated by the energy management unit 130.

The first switch unit 103 of FIG. 1 is provided between the breaker unit 101 and the first power converter 11 to separate the system when there is an unnecessary excitation current consumption in the first power converter 11. To prevent the consumption of the excitation current. Similarly, the second switch unit 105 is provided between the breaker 101 and the second power converter 19 to isolate the system when there is an unnecessary excitation current consumption in the second power converter 19. Prevents the consumption of excitation currents.

The detection unit 107 includes a current sensor or a voltage sensor provided on the main circuit breaker and the branch circuit breaker in the breaker 101, an amplifying circuit for amplifying an output signal of the current sensor or the voltage sensor, and a digital signal output of the amplifying circuit. A conversion circuit for converting the circuit into a circuit is provided, and the voltage value on the system and the current value in the branched wiring are detected. The current sensor corresponds to a zero current transformer (ZCT) or a current transformer (CT) for sensing current, and the voltage sensor corresponds to a potential transformer (PT) for detecting a voltage. do. The current sensor needs to be installed in each branch to detect the quarterly power consumption, but the voltage sensor may be installed only in the main wiring.

The detector 107 provides the detected current value or voltage value to the energy manager 130.

The display unit 109 displays on the screen so that the user visually recognizes a graphic interface for receiving various information, an alarm, or a user's control command provided by the energy management unit 130. It may be displayed through a lamp, etc., the input unit 111 receives various information or control commands from the user and provides the energy management unit 130.

The communication unit 113 includes a communication interface capable of communicating with an external device such as an external energy management server 27 or an administrator terminal 29 to mediate communication between the energy management unit 130 and the external device. In general, the general management state by the energy management unit 130 is provided to the manager terminal 29 through the external energy management server 27.

The energy management unit 130 controls the overall operation of the intelligent distribution panel 100 of the present invention. Basically, the energy management unit 130 may perform basic control operations for the display unit 109, the input unit 111, and the communication unit 113, and these functions are not characteristic parts of the present invention. do.

However, first, the distribution of energy on the system will be briefly described. The commercial AC grid, that is, the AC power of the commercial AC power supply side 13 is supplied to the system via the smart meter 15 and the blocking unit 101, and the renewable energy produced by the renewable energy device is the first power converter. (11), power is supplied to the system via the first switch unit 103 and the breaker unit 101.

On the other hand, renewable energy produced by the AC power and the renewable energy device of the commercial AC power supply side 13 may be stored in the energy storage device 17 as needed, energy stored in the energy storage device 17 is also required. Can be discharged to the system. Such system control by charging to the energy storage device 17 and discharge control from the energy storage device 17 is particularly performed by the energy management unit 130.

Energy management by the energy management unit 130 is made in the form of blocking the control of the system and unnecessary power, for this purpose, the system control unit 131, the monitoring unit 133, the power output unit 135 and the excitation current control unit ( 137) to perform characteristic energy management of the present invention.

The grid control unit 131 controls the second power converter 19 to control charging or discharging between the renewable energy or commercial AC power supply side 13 and the energy storage device 17.

First, the renewable energy produced by the renewable energy device or the energy supplied from the commercial AC power supply side 13 passes through the cut-off unit 101, the second switch unit 105, and the second power converter 19. The power stored in the storage device 17 and stored in the energy storage device 17 is supplied to the load 23 or the commercial AC power supply side 13 through the reverse path. At this time, the second power converter 19 forms a charging or discharging path thereof, and the operation of the second power converter 19 is controlled by the system controller 131.

Here, the system control unit 131 reads the real-time electricity rate information based on the smart grid from the smart meter 15, and automatically charges the renewable energy or commercial AC power to the energy storage device 17 according to the rate information. The energy stored in the energy storage device 17 may be controlled to be discharged to the commercial AC power supply side 13 or the load 23.

For example, the system control unit 131 charges the energy storage device 17 with renewable energy or commercial AC power when the electric charge is low, and the commercial AC power supply side 13 or the load 23 when the electric charge is expensive. The second power converter 19 may be controlled to discharge the same. As another example of control, the system control unit 101 may charge the energy storage device 17 during the day time when the renewable energy using solar heat is transmitted, and discharge the energy storage device 17 at night time.

Under the control of the grid control unit 131, the energy distributed through the intelligent distribution panel 100 is not simply charged or discharged by an electrical factor, but based on various factors including economic factors by a smart grid. It can be managed by a comprehensive energy management method.

The power calculating unit 135 calculates and displays not only the total power consumption on the main wiring, but also the power consumption on the branch wiring, and the effective power consumption due to the leakage of electricity in each branch.

The power value in the main wiring can be confirmed by receiving the output value of the separate power meter installed in the breaker 101 through the detector 107.

To detect the quarterly power consumption, the power calculation unit 135 uses that the power consumption in each branch is proportional to the current value in each branch. The power calculation unit 135 receives the voltage value and the current value at the branch breaker from the detector 107, and then calculates the quarterly power value proportional to the current value at each branch breaker from the power value at the main wiring. .

The power calculator 135 may display the quarterly current value and the power value through the display unit 109, or provide the branched current value and the power value to an external energy management server 27.

In this way, it is possible to accurately measure the power of each branch breaker without having to provide expensive power measuring equipment for each branch breaker. In addition, the power calculation unit 135 can directly control the power consumption by comparing the power value calculated for each quarter with the power pattern previously stored in the storage medium, and directly cut off the system for each quarter according to a separate power control algorithm. It may be.

In addition, the power calculating unit 135 may calculate the effective power consumption due to leakage of electricity such as a short circuit and display the same through the display unit 109. In this case, the effective power consumption due to the short circuit may be obtained as in Equation 1 below.

The leakage current can be detected by using an image current transformer ZCT in the detector 107.

Through this, the intelligent distribution panel 100 can calculate and manage the power consumption due to leakage even in a state in which the leakage is less than the rated leakage current, which is the reference of the circuit breaker operation, and thus is not blocked by the circuit breaker.

In addition, according to an embodiment of the present invention, the power calculation unit 135 may calculate and display the power consumption of the circuit breaker itself. In this case, the power consumption of the circuit breaker itself may be calculated as in Equation 2 below.

Here, the voltage drop in the breaker refers to the voltage difference between the input terminal and the output terminal of the circuit breaker. Of course, depending on the direction of the power system, the input and output terminals of the breaker may be opposite to each other.

In addition, if necessary, the power calculation unit 135 may cause the detection unit 107 to generate a trip signal for operating the trip unit of the main wiring breaker or the branch breaker of the breaker 101, thereby shutting down the system.

The monitoring unit 133 receives and processes various types of information related to renewable energy from the electrical safety monitoring device 25, and provides the external energy management server 27 through the communication unit 113 to the administrator of the renewable energy device. Allows you to monitor normal operation and manage safety.

The excitation current control unit 137 checks the first power converter 11 and the second power converter 19 and, if there is no need for operation, cuts off the system to block unnecessary excitation current consumption.

For example, if there is no supply of renewable energy from the renewable energy device, the excitation current control unit 137 operates the first switch unit 103 to between the breaker 101 and the first power converter 11. Shut off the connected grid.

In addition, the excitation current control unit 137 checks the control state of the battery operating device 21 and determines that there is no charge or discharge to the energy storage device 17, that is, the role of the second power converter 19 is unnecessary. If it is determined that the case, by operating the second switch unit 105 to cut off the system connected between the breaker 101 and the second power converter 19.

Here, the first power converter 11 and the second power converter 19 will be described using the second power converter 19 shown in FIG. 2 as an example. 2, the second power converter 19 includes a DC / DC converter 201, an inverter unit 203, a filter unit 205, and a transformer 207.

The DC / DC converter 201 adjusts the magnitude of the DC voltage provided in the DC system like the energy storage device 17 and the inverter unit 203. An inverter unit 203 is provided between the DC / DC converter 201 and the transformer 207 to convert direct current into alternating current or direct current into direct current, and the filter unit 205 includes the inverter unit 203 and the transformer 207. ) To filter the signal of the desired frequency band. The transformer 207 is a grid-connected transformer and is used to link different types of power systems (eg, between three-phase alternating current and single phase alternating current).

By this configuration, the second power converter 19 converts an AC power source, for example, a three-phase AC power source of 380V (volts) into a DC power source that can charge the energy storage device 17, The DC power converted by the power converter 19 is charged in the energy storage device 17.

On the contrary, the energy stored in the energy storage device 17 is converted into AC power through the DC / DC conversion unit 210, the inverter unit 220, the filter unit 230, and the transformer 207, so that the load 23 or It is supplied to the commercial AC power supply side 13.

As described in the background art, the transformer 207 consumes an excitation current which is basically a quiescent current even when there is no charge or discharge of the energy storage device 17. The excitation current control unit 137 checks the battery operating device 21 and when there is no charge or discharge of the energy storage device 17, opens the second switch unit 105 to connect the grid to the second power conversion device 19. To prevent the excitation current from being supplied.

Similarly, the excitation current control unit 137 opens the first switch unit 103 when there is no energy supply from the renewable energy device to cut off the grid connection to the first power converter 11 so that the excitation current is not supplied. will be.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

Claims (6)

In the intelligent distribution panel,
Branching with a main power circuit breaker provided on a grid branched to a first power converter or a second power converter connecting an energy storage device to the grid, and a commercial AC power source and a load side respectively. Breaker for branching the power on the system having a circuit breaker;
By controlling the second power converter in accordance with the electric charge provided from the smart meter connected to the commercial AC power supply, the energy stored in the energy storage device is charged or stored in the energy storage device. Intelligent distribution panel including a grid control unit for discharging through the blocking unit.
The method of claim 1,
The system control unit,
When the electric charge is low, the second power conversion device is controlled to charge the energy storage device with energy distributed through the blocking unit,
And when the electric charge is high, controlling the second power converter to discharge the energy storage device charged in the energy storage device.
The method of claim 1,
A first switch unit and a second switch unit provided between the first and second power converters and the blocking unit to control the system; And
When the first and second power converters are in the idle state, the first switch unit and the second switch unit are opened to turn off the system between the first and second power converters and the cutoff unit, respectively. Intelligent distribution panel further comprising an excitation current control unit for blocking the consumption of the excitation current in the first and second power converter.
The method of claim 1,
A detector for measuring current consumption for each branch in the blocking unit;
A display unit for displaying the information so that the information can be visually recognized; And
The apparatus may further include a power calculation unit configured to receive the quarterly current consumption from the detection unit, calculate a quarterly power consumption proportional to the quarterly current consumption based on the power consumption value of the main wiring, and display the same by the display unit. Intelligent distribution board.
5. The method of claim 4,
The detection unit also measures the leakage current for each branch in the blocking unit,
And the power calculation unit calculates and displays the effective power consumption due to the short circuit leakage in the branch using the following quarterly leakage current value measured by the detection unit and displays the calculated power in the following equation.
≪ Equation &
Active power consumption due to leakage = sensed effective leakage current × voltage
5. The method of claim 4,
The power calculation unit,
The power consumption of each breaker in the breaker is calculated according to the following equation and displayed on the display unit,
≪ Equation &
Breaker Power Consumption = Voltage Drop × Current
And the voltage drop is a voltage difference between an input terminal and an output terminal of the circuit breaker.

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