TWI814174B - Voltage control method - Google Patents

Abstract

A voltage control method provides a power regulation system and an artificial intelligence algorithm to control the voltage on a three-phase feeder line from a load side of a transformer to a client load in a power distribution system. Specifically, the power regulation system is connected to the three-phase feeder line on the load side of the transformer, and connected in parallel with the client load. Subsequently, the artificial intelligence algorithm is used to analyze three-phase voltage on the three-phase feeder line of the load side to generate three phase compensation powers, and make the sum of the three phase compensation powers equal to zero. According to the three phase compensation powers, the power regulation system adjusts the voltage amplitudes and voltage phase angles of different single-phase feeder lines respectively, to control the three single-phase voltages provided from the load side of the transformer to the client load.

Description

Voltage control method

The present invention relates to a voltage control method, and in particular to a method applied to control the user terminal voltage of a power distribution system.

In terms of functions, the main components of the power system can be roughly divided into three subsystems: power generation, power transmission, and power distribution. The power transmission system connects the power generation system and the power distribution system. Its function is to transport the electric energy produced by the power generation system to the substation or large industrial and commercial users near the user end; and then through the power distribution system in the substation, the electric energy transmitted by the transmission system is Appropriate voltage levels are distributed to the loads at each user end. Among them, the factors that affect the power quality of the distribution system mainly include three-phase imbalance and short-term large currents during power supply.

Electric power companies are committed to maintaining the balance of three-phase voltage and current regardless of the stages of power generation, transmission or distribution. The ideal three-phase voltage and current are equal in magnitude for each phase, and the phase angle difference between any two phases is 120°. If the magnitude or angle of the three-phase voltage and current deviates from the above conditions, it is called three-phase voltage and current imbalance. In reality, the imbalance of three-phase voltage and current is a long-standing problem.

Since the feeder structure of the power distribution system is relatively complex, and the time at which each user's load is put into and out of the system is uncertain, the three-phase voltage and current imbalance will be more significant in the power distribution system, and the voltage and current between the transmission system and the distribution system are Imbalances affect each other. In terms of voltage unbalance, when three When the phase voltage deviation is too large, causing the voltage to become unbalanced, it will also lead to the emergence of unbalanced current, which will lead to problems such as temperature rise, efficiency drop, and loss increase of electrical equipment. Therefore, voltage imbalance has a huge impact on the electrical equipment at the user end, and it is necessary to conduct research to solve the problem of voltage imbalance at the user end.

However, most of the current technologies focus on improving the three-phase current imbalance, with less discussion on voltage imbalance and lack of practical feasibility. For example, the method of transformer wiring adjustment or feeder reorganization requires continuous switching and phase switching according to different load users. However, the actual user load has high time variability, so the effect is not effective; and power electronic transformers have rated power capacity. Due to limitations, it is currently unable to replace traditional power transformers; power spring devices (electric springs) may be limited by the settings of critical loads and noncritical loads, and may not be applicable to all users. Intelligent soft switches (Soft Open Points, SOP) can only be used in contact switches, and their use places are relatively limited.

When engaged in power distribution projects or system dispatching to avoid equipment overload and isolate faults, load transfer operations are sometimes required. When load transfer is performed in a power distribution system in a non-power outage manner, the transfer feeders belong to different substations and the loads on the two feeders are different. Therefore, when the load is transferred from the original power supply feeder to the new power supply feeder, in addition to the possible unbalance of the three-phase voltage and current, the impact of the voltage amplitude difference and voltage phase angle difference between different feeders may also cause "short-term "High current" phenomenon, an unexpected abnormal power flow will occur at the moment the contact switch is turned on. This phenomenon may cause the protective relay to operate, causing regional power outages, thereby affecting the reliability of power supply.

For short-term large currents in power transfer, there are currently several possible improvement methods, including: On Load Tap Changer (OLTC), static reactive power compensator (static var compensator, SVC), static Synchronous compensation (Static Synchronous Compensator, STATCOM), shunt capacitor, and phase shift transformer. Among them, OLTC, SVC, STATCOM Control methods such as these all aim at correcting the voltage amplitude and do not consider changes in voltage phase angle. Although they can improve the voltage difference between the two ends of the contact switch, they are not effective in dealing with the phase angle difference, so there is still a high chance. Generate large current.

In addition, although the voltage magnitude and phase angle can be improved simultaneously by using a phase-shifting transformer, the phase-shifting transformer must be connected in series to the circuit, which will affect the reliability of the power grid and make it difficult to popularize and apply it.

One object of the present invention is to provide a voltage control method that can be used to simultaneously solve the problem of three-phase unbalance in the power distribution system and the problem of transferring medium and short-term large currents.

One object of the present invention is to provide a voltage control method that utilizes a distributed energy storage system to improve the power quality of a power distribution system.

In order to achieve the above object, the present invention uses a voltage control method to control the voltage of a power system. This power system includes a three-phase power supply and a transformer. The transformer has a power side and a load side. The power side is connected to the three-phase power supply. The load side has a three-phase feeder, which includes a U-phase feeder, a V-phase feeder and a W A phase feeder is used to provide three-phase voltage to a load, in which the U-phase feeder provides a U-phase voltage amplitude and a U-phase voltage phase angle, and the V-phase feeder provides a V-phase voltage amplitude and a V-phase voltage phase angle, And the W-phase feeder provides a W-phase voltage amplitude and a W-phase voltage phase angle. The above method includes: connecting a power conditioning system to the three-phase feeder on the load side of the transformer, and connecting the power conditioning system in parallel with the load; providing an artificial intelligence algorithm to analyze the three-phase voltage on the load side to generate Three-phase compensation power, and the sum of the three-phase compensation power is zero; and the power adjustment system adjusts the U-phase voltage amplitude and U-phase voltage phase angle of the U-phase feeder according to the three-phase compensation power, and adjusts the V of the V-phase feeder. phase voltage amplitude and V-phase voltage phase angle, and adjust the W-phase voltage amplitude and W-phase voltage phase angle of the W-phase feeder to control the transformer respectively. The load side of the device provides three-phase voltage to the load.

In one embodiment, the power conditioning system includes an energy storage device. The energy storage device provides a U-phase power line, a V-phase power line and a W-phase power line. The U-phase power line is connected to the U-phase feeder, and the V-phase power line is connected to the U-phase feeder. The power line is connected to the V-phase feeder line, and the W-phase power line is connected to the W-phase feeder line.

In one embodiment, the above method further includes: providing a feedback control mechanism so that the power system generates a voltage amplitude feedback signal and a voltage phase angle feedback signal; and the artificial intelligence algorithm refers to the feedback signal returned by the power system. The voltage amplitude feedback signal and voltage phase angle feedback signal are used to generate three-phase compensation power.

In one embodiment, the power system includes a first branch line, a second branch line and a tie switch. The first branch line and the second branch line are both electrically connected to the three-phase power supply, and the tie switch is connected to the first branch line and the second branch line. between branches. The above method further includes: connecting the power side of the transformer to at least one of the first branch line and the second branch line in parallel to the tie switch.

In one embodiment, the two ends of the tie switch have a voltage amplitude difference and a voltage phase angle difference. The above method further includes: activating the power regulation system to make both the voltage amplitude difference and the voltage phase angle difference smaller; And when the voltage amplitude difference and voltage phase angle difference become smaller to meet a threshold condition, the tie switch forms a path state, so that the load on the first branch line can receive the power transferred from the second branch line through the tie switch without interruption of power supply. Comes electricity.

In one embodiment, the above method further includes: an artificial intelligence algorithm determines a target voltage amplitude and a target voltage phase angle based on the voltage at one of the two ends of the tie switch; and provides a feedback control mechanism to make the power The system generates a voltage amplitude feedback signal, a voltage phase angle feedback signal and a current feedback signal; and the artificial intelligence algorithm receives the voltage amplitude feedback signal, voltage phase angle feedback signal and current returned from the power system. feedback signal and refer to the target voltage amplitude and target voltage phase angle to generate The three-phase compensation power makes both the voltage amplitude difference and the voltage phase angle difference approach zero.

In one embodiment, the above method further includes: providing a segmented switch, disposed on one of the first branch line and the second branch line, and located between the three-phase power supply and the tie switch; and causing the segmented switch to form a Open circuit condition, subsequently stopping the power regulation system.

In one embodiment, the sectional switch is provided on the first branch. The above method further includes: providing a second transformer and a second power conditioning system. The second transformer has a second power side and a second load side. The second power conditioning system is connected to the second load side; and the second power supply side is connected to the first branch line and is located between the segment switch and the three-phase power supply.

In one embodiment, the above method further includes: the power conditioning system provides a controllable current source, and the artificial intelligence algorithm performs a current calculation to control the controllable current source.

The method of the present invention uses the power regulation system to separately control the voltage amplitude and voltage phase angle on different single-phase feeders on the load side of the distribution transformer or the user-end load under the condition that the sum of the three-phase compensation power is zero, so as to achieve three Phase voltage balance. Moreover, this method can also be used to adjust the voltage on the feeders at both ends of the tie switch in a transfer system to avoid short-term large currents during transfer.

100:Power system

110: Three-phase power supply

120,120A,120B: Distribution transformer

130:Load

121:Power side

122:Load side

122u: U phase feeder

122v:V phase feeder

122w:W phase feeder

140:Underground cable

150, 150A, 150B: Power conditioning system

152:Energy storage device

150u: U phase power cord

150v: V phase power cord

150w:W phase power cord

160:Artificial Intelligence Algorithm

170:Bus

200, 200A: Power system

210:Contact switch

210A, 210B: transfer point

220, 220A, 220B: Distribution transformer

230: Segment switch

240A, 240B: transfer transformer

250, 250A, 250B: Power conditioning system

A, B: Branch line

CPu, CPv, CPw: compensation power

SA, SB: three-phase equivalent power supply

S10: Feedback control machine rotation

S11~S14, S16~S17: Steps of feedback control machine rotation

Figure 1 is a schematic diagram of the basic architecture of a power system applying the voltage control method of the present invention.

FIG. 2 is a schematic diagram of a feedback control mechanism according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a power system architecture used to improve the transfer of medium and short-term large currents according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of a power system architecture for simultaneously improving three-phase voltage balance and transferring short- and medium-term large currents according to an embodiment of the present invention.

The aforementioned and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of a preferred embodiment with reference to the drawings. Directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only used to refer to the directions of the accompanying drawings. Therefore, these directional terms are only used to illustrate and not to limit the present invention.

Figure 1 is a schematic diagram of the basic circuit structure of a power system applying the voltage control method of the present invention. The power system 100 in this embodiment takes a single feeder network as an example. This single feeder network is part of a power distribution system. Its basic circuit structure includes a three-phase power supply 110, a distribution transformer 120 and a load 130. The three-phase power supply 110 includes a three-phase equivalent power supply, such as three-phase power transmitted from a power transmission system, or three-phase power transferred from another power distribution system. The distribution transformer 120 has a power side 121 (also called a primary side) and a load side 122 (also called a secondary side). The power side 121 is connected to the three-phase power supply 110, and the load side 122 provides a three-phase feeder, which passes through An underground cable 140 transmits power to the user's load 130 . In one embodiment, the voltage level of the three-phase power supply 110 is 11.4kV or 22.8kV, and the voltage of the load side 122 of the distribution transformer 120 is 220V/380V.

The feeders on the load side 122 include a U-phase feeder 122u, a V-phase feeder 122v and a W-phase feeder 122w for providing three-phase voltages to the load 130 . U-phase feeder 122u provides a U-phase voltage amplitude and a U-phase voltage phase angle; V-phase feeder 122v provides a V-phase voltage amplitude and a V-phase voltage phase angle; and W-phase feeder 122w provides a W-phase voltage amplitude And a W-phase voltage phase angle.

In order to improve the three-phase voltage imbalance on the feeder of the load side 122 of the distribution transformer 120, this embodiment connects a power conditioning system 150 to the feeder of the load side 122 of the distribution transformer 120, so that it is connected in parallel with the load 130, and provides a The artificial intelligence algorithm 160, the power adjustment system 150 is based on artificial intelligence The power commands provided by the smart algorithm 160 are used to respectively adjust the three-phase power of the feeder on the load side 122 . The power conditioning system 150 includes an energy storage device 152 connected in parallel with the load 130 to the three-phase feeder of the load side 122 of the distribution transformer 120 . The energy storage device 152 provides a U-phase power line 150u, a V-phase power line 150v and a W-phase power line 150w, wherein the U-phase power line 150u is connected to the U-phase feeder 122u, and the V-phase power line 150v is connected to the V-phase Feeder 122v, and W-phase power line 150w is connected to W-phase feeder 122w. The power lines of the power conditioning system 150 and the feed lines of the load side 122 may be connected by means of busbars 170 .

The artificial intelligence algorithm 160 analyzes the three-phase voltages on the load side 122 to generate three single-phase compensation powers CPu, CPv, and CPw, and the sum of the three-phase compensation powers CPu, CPv, and CPw is zero. In practice, the compensation power CPu, CPv, CPw of each single phase is an apparent power. The power adjustment system 150 adjusts the U-phase voltage amplitude and U-phase voltage phase angle of the U-phase feeder 122u, and adjusts the V-phase voltage amplitude and V of the V-phase feeder 122v according to the three single-phase compensation powers CPu, CPv, and CPw. phase voltage angle, and adjust the W-phase voltage amplitude and W-phase voltage angle of the W-phase feeder 122w to respectively control the three-phase voltages on the load side of the transformer.

。不平衡指標d0為各相電壓中零序成分與正序成分之比例；不平衡指標d2為各相電壓中負序成分與正序成分之比例。終止條件為最大疊代次數MaxItr(100次)或適應函數小於1%。 Since there are many artificial intelligence algorithms 160 and it is impossible to describe them one by one, the particle swarm optimization algorithm (Particle swarm optimization) is used here to solve the three-phase compensation powers CPu, CPv, and CPw required for three single phases. Based on the three-phase compensation powers CPu, CPv, and CPw, the power conditioning system 150 injects current into different feeders to actually achieve the effect of regulating the power of each phase of the feeder from the load side 122 to the user end. The fitness function of the particle swarm optimization algorithm is recommended to be based on the quadratic power of the imbalance index (d0, d2). For example, the least sum of squares method is used to increase convergence. The formula is:

. The unbalance index d0 is the ratio of the zero sequence component and the positive sequence component in each phase voltage; the unbalance index d2 is the ratio of the negative sequence component and the positive sequence component in each phase voltage. The termination condition is the maximum number of iterations MaxItr (100 times) or the fitness function is less than 1%.

FIG. 2 is a schematic diagram of a feedback control mechanism according to an embodiment of the present invention. In order to reduce the voltage amplitude difference and voltage phase angle difference between different feeders, for example: reduce the voltage amplitude difference and voltage phase angle imbalance between feeders of different phases, or reduce the voltage amplitude difference and voltage phase angle difference between feeders at both ends of the tie switch. Based on the voltage amplitude difference and voltage phase angle difference, the artificial intelligence algorithm 160 of the present invention cooperates with a feedback control machine (S10) to obtain the compensation powers CPu, CPv, and CPw of each phase required by the power conditioning system 150.

First, the artificial intelligence algorithm 160 obtains the current voltage amplitude feedback signal (S11), voltage phase angle feedback signal (S12), and current feedback signal (S13) returned from the power system 100. In this embodiment, the voltage amplitude feedback signal (S11) and the voltage phase angle feedback signal (S12) are generated by Fourier transforming (S15) the voltage signal (S14) of the power system 100. According to the voltage amplitude feedback signal (S11) and voltage phase angle feedback signal (S12) of the current voltage on different feeders, the artificial intelligence algorithm 160 determines a target voltage amplitude (S16) and a target voltage phase angle (S17) , which makes the voltage amplitude difference and voltage phase angle difference between different feeders closer to zero. Next, the artificial intelligence algorithm 160 calculates the real work and virtual work required by the power conditioning system 150 based on the target voltage amplitude and target voltage phase angle, and provides corresponding compensation powers CPu, CPv, and CPw to different feeders respectively. The power adjustment system 150 adjusts the voltage amplitude and voltage phase angle of different feeders respectively according to the compensation powers CPu, CPv, and CPw of different feeders, so as to promote the voltage on the user feeder in the power system 100 to be closer to balance. By repeatedly running the above process until the voltage amplitude difference and voltage phase angle difference are lower than a threshold condition, for example, when the adaptation function of the artificial intelligence algorithm 160 is less than 1%, the goal can be regarded as achieved.

In addition to improving the problem of three-phase voltage imbalance, the voltage control method of the present invention can also be used to improve the problem of transferring medium and short-term large currents.

FIG. 3 is a schematic diagram of a power system architecture used to improve the transfer of medium and short-term large currents according to an embodiment of the present invention. The power system 200 includes a branch line A, a branch line B and a contact switch 210, where the branch line A has a distribution transformer 220, a section switch 230 and a power conditioning system 250. Branch A and Branch B are connected to the same transmission system through two different substations. These two different substations can be regarded as two different three-phase equivalent power supplies SA and SB, providing different three-phase voltages to branch line A and branch line B respectively. In addition, in this embodiment, transfer transformers 240A and 240B can be installed on branch line A and branch line B respectively according to actual needs, between two three-phase equivalent power supplies SA and SB and the tie switch 210 . The end of branch line A and the end of branch line B are connected through a tie switch 210, whereby power can be selectively supplied to each other. In this embodiment, the segment switch 230 is provided on the branch line A and is located between its three-phase equivalent power supply SA and the tie switch 210 . In normal times, branch line A and branch line B are powered by their respective three-phase equivalent power supplies SA and SB, and do not need to transfer power to each other. Therefore, the tie switch 210 is in the off-circuit state, and the segment switch 230 is in the on-circuit state.

When the load of branch line A and branch line B is greater, the voltage amplitude difference and voltage phase angle difference between the bus bars of the two transfer points 210A and 210B will be greater, causing an abnormal voltage to occur at the moment when the tie switch 210 forms a path. Large current. In order to solve this problem, this embodiment sets the power conditioning system 250 on the load side of the distribution transformer 220A at the transfer point 210A at the end of branch line A, and cooperates with the artificial intelligence algorithm 160 to implement the voltage control method of the present invention to reduce the size of the tie switch. The voltage amplitude difference and voltage phase angle difference between the two ends of 210.

After adding the power conditioning system 250, the power supply transfer process from branch line B to branch line A is: the power conditioning system 250 starts to operate through manual or automatic startup; the voltage control method of the present invention is implemented to reduce the voltage between the two ends of the tie switch 210. Voltage amplitude difference and voltage phase angle difference; when both the voltage amplitude difference and the voltage phase angle difference between the two ends of the tie switch 210 become smaller and meet a threshold condition, the tie switch 210 forms a pass state and causes branch line B to Start supplying power to branch line A, so that the load on branch line A can receive the power transferred from branch line B through the contact switch 210 without interruption; then, to end the transfer, the segment switch 230 is Open circuit state; finally, the operation of the power conditioning system 250 is stopped.

In order to reduce the voltage amplitude difference and voltage phase angle difference between the two ends of the tie switch 210, the artificial intelligence algorithm 160 determines a target voltage amplitude and a target voltage based on the voltage at at least one of the two ends of the tie switch 210. phase angle; and the power adjustment system 250 operates according to the feedback control mechanism proposed by the present invention (S10), obtains the voltage amplitude difference and voltage phase angle difference between the two ends from the tie switch 210, and then obtains the power adjustment system through the artificial intelligence algorithm 160 The required power command of 250 makes the aforementioned two differences close to 0 to achieve the feedback target.

Figure 4 shows that the voltage control method and power regulation system of the present invention are suitable for application in two different locations on branch line A and branch line B of the power system 200A: one is located on branch line A (the left dotted box in Figure 4) or branch line B , to improve the voltage imbalance problem between different phase feeders on the same branch line; the second is located at the transfer point (right dotted box in Figure 4), that is, the end of the two lines A or/and B, to improve connection The problem of voltage imbalance between the same-phase feeders on different branches A and B at both ends of the switch 210 is thereby avoided to avoid the occurrence of short-term large current.

Since Figure 4 is only a schematic diagram and the actual application architecture generally depends on different needs, the transfer transformer is omitted. The transformers shown in Figure 4 are all distribution transformers. In Figure 4, the power conditioning system 150A in the left dotted box is configured on branch A and is connected in parallel with a load on the load side of the distribution transformer 120A. It is mainly responsible for improving the three-phase voltage imbalance problem of its adjacent load. The distribution transformer The 120A power supply side is connected between the sectional switch 230 on branch line A and the three-phase equivalent power supply SA; the power conditioning systems 250A and 250B in the right dotted box are respectively configured with two transfer points 210A and 210B, and are mainly responsible for improving The problem of transferring large current. In one embodiment, the power conditioning systems 250A and 250B located at both ends of the tie switch 210 may be the same. In this case, both ends of the tie switch 210 share a power conditioning system. In Figure 4, the downward arrows on the left side of the power conditioning systems 150A, 150B, 250A and 250B all represent user feeders or loads, which are connected in parallel with the power conditioning systems 150A, 150B, 250A and 250B at the distribution transformer respectively. Load side of 120A, 120B, 220A and 220B.

The power conditioning system 250A and/or 250B of this embodiment provides a controllable current source, and after the artificial intelligence algorithm 160 performs the power calculation, a current calculation is performed to obtain a current command to control the controllable current source pair. The compensation current of the power system 200 or 200A further causes both the voltage amplitude difference and the voltage phase angle difference across the tie switch 210 to approach 0.

In this embodiment, the artificial intelligence algorithm 160 sends the three-phase compensation powers CPu, CPv, and CPw to the power conditioning systems 250A and/or 250B in each iteration under the premise that the circuit architecture of the power systems 200 and 200A is unknown, so that The power conditioning system 250A and/or 250B sends a set of compensation current values accordingly. Then, in conjunction with the voltage amplitude feedback, voltage phase angle feedback and current feedback, capture the three-phase voltage values of the bus 170 at this time and observe whether the three-phase voltage unbalance rate (ie, the adaptation function) is improved, and repeat the overlapping generation process until the user-side voltage unbalance rate is within 1%, and finally a set of appropriate compensation current solutions are found; and the total compensation apparent power of the three phases is 0VA, whereby the voltage amplitude and voltage of the three-phase power can be adjusted phase angle. In one embodiment, when the absolute value of the three-phase total compensated apparent power is less than 10 ^-4 VA, it is regarded as 0VA.

To sum up, the method of the present invention utilizes a power regulation system and a feedback control machine which includes feedback of voltage amplitude and voltage phase angle, and can respectively control the three-phase compensation power under the condition that the sum of the three-phase compensation power is zero. The voltage amplitude and voltage phase angle on different single-phase feeders on the load side of the distribution transformer or user-end load to achieve three-phase voltage balance. In addition, the method of the present invention can also be used to adjust the voltage on the feeders at both ends of the tie switch in a power transfer system to avoid short-term large currents during power transfer. Accordingly, the present invention has different technical features from the conventional techniques, and it is difficult for a person with ordinary knowledge in the field to easily ascertain the concept of the present invention from the conventional techniques. Therefore, the present invention should be novel and progressive.

However, the above are only preferred embodiments of the present invention, and should not be used to limit the scope of the present invention. Equivalent changes and modifications are still within the scope of the patent of the present invention. In addition, any embodiment or patentable scope of the present invention does not need to achieve all the purposes, advantages or features disclosed in the present invention. In addition, the abstract section and title are only used to assist in searching patent documents and are not intended to limit the scope of the invention.

100:Power system

110: Three-phase power supply

120:Distribution transformer

130:Load

121:Power side

122:Load side

122u: U phase feeder

122v:V phase feeder

122w:W phase feeder

140:Underground cable

150:Power adjustment system

152:Energy storage device

150u: U phase power cord

150v: V phase power cord

150w:W phase power cord

160:Artificial Intelligence Algorithm

170:Bus

CPu, CPv, CPw: compensation power

Claims (9)

A voltage control method suitable for controlling the voltage of a power system, wherein the power system includes a three-phase power supply and a transformer, the transformer has a power supply side and a load side, the power supply side is connected to the three-phase power supply, and the load side There is a three-phase feeder, which includes a U-phase feeder, a V-phase feeder and a W-phase feeder, used to provide three-phase voltage to a load, wherein the U-phase feeder provides a U-phase voltage amplitude and a U-phase voltage phase angle. , the V-phase feeder provides a V-phase voltage amplitude and a V-phase voltage phase angle, and the W-phase feeder provides a W-phase voltage amplitude and a W-phase voltage phase angle, the method includes: placing the load on the transformer The three-phase feeder on the side is connected to a power conditioning system, and the power conditioning system is connected in parallel with the load; an artificial intelligence algorithm is provided to analyze the three-phase voltage on the load side to generate three-phase compensation power, and Make the sum of the three-phase compensation power equal to zero; and the power adjustment system respectively adjusts the U-phase voltage amplitude and the U-phase voltage phase angle of the U-phase feeder according to the three-phase compensation power, and adjusts the U-phase voltage phase angle of the V-phase feeder. The V-phase voltage amplitude and the V-phase voltage phase angle, and the W-phase voltage amplitude and the W-phase voltage phase angle of the W-phase feeder are adjusted to respectively control the load side of the transformer to provide the load. three-phase voltage. The method of claim 1, wherein the power conditioning system includes an energy storage device that provides a U-phase power line, a V-phase power line, and a W-phase power line, wherein the U-phase power line is connected In the U-phase feeder line, the V-phase power line is connected to the V-phase feeder line, and the W-phase power line is connected to the W-phase feeder line. The method described in claim 1 further includes: providing a feedback control mechanism to cause the power system to generate a voltage amplitude feedback signal and a voltage phase angle feedback signal; and The artificial intelligence algorithm refers to the voltage amplitude feedback signal and the voltage phase angle feedback signal returned from the power system to generate the three-phase compensation power. The method of claim 1, wherein the power system includes a first branch line, a second branch line and a contact switch, the first branch line and the second branch line are both electrically connected to the three-phase power supply, and the contact switch The switch is connected between the first branch line and the second branch line, and the method further includes: connecting the power side of the transformer in parallel with at least one of the first branch line and the second branch line to the tie switch. The method described in claim 4, wherein the two ends of the contact switch have a voltage amplitude difference and a voltage phase angle difference, the method further includes: activating the power conditioning system to make the voltage amplitude difference and the voltage phase angle difference Both the angle differences become smaller; and when the voltage amplitude difference and the voltage phase angle difference become small enough to meet a threshold condition, the contact switch forms a pass state, so that the load on the first branch line is in an uninterruptible power supply situation. Next, receive the power transferred from the second branch line through the contact switch. The method described in claim 5 further includes: the artificial intelligence algorithm determines a target voltage amplitude and a target voltage phase angle based on the voltage at one of the two ends of the tie switch; and provides a feedback control machine. to cause the power system to generate a voltage amplitude feedback signal, a voltage phase angle feedback signal and a current feedback signal; and the artificial intelligence algorithm receives the voltage amplitude feedback signal returned from the power system, The voltage phase angle feedback signal and the current feedback signal are referred to the target voltage amplitude and the target voltage phase angle to generate the three-phase compensation power, causing both the voltage amplitude difference and the voltage phase angle difference to approach zero. The method of claim 5 further includes: providing a sectional switch, disposed on one of the first branch line and the second branch line, and located between the three-phase power supply and the tie switch; and The sectional switch is brought into an open-circuit state, and then the power conditioning system is stopped. The method of claim 7, wherein the segment switch is disposed on the first branch line, the method further includes: providing a second transformer and a second power conditioning system, the second transformer having a second power side and a second load side, wherein the second power conditioning system is connected to the second load side; and the second power supply side is connected to the first branch and is located between the sectional switch and the three-phase power supply. The method of claim 1 further includes: the power conditioning system provides a controllable current source, and the artificial intelligence algorithm performs a current calculation to control the controllable current source.

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