Power supply method, device, equipment and medium for main transformer-to-low switching system

Abstract

The invention discloses a power supply method, device and equipment for a main transformer to low switching system and a medium. The power supply method comprises the step of determining the load information of the main transformer to low switch according to the ratio of the current current information to the safety current information of the main transformer to low switch. And comparing the load information with the first safety threshold information and the second safety threshold information. And when the load information is greater than or equal to the first safety threshold value information and less than or equal to the second safety threshold value information, adjusting the reactive power of the main transformer to low switch through the reactive power adjusting device, and adjusting the bus voltage of the bus to be within a first range through the on-load voltage regulating transformer. Thus, the load information of the main transformer to low switch is monitored in real time, the reactive power of the main transformer to low switch system is balanced in advance so as to improve the power factor of the main transformer to low switch system, and meanwhile, the bus voltage of the bus is adjusted to be within the first range through the on-load voltage regulating transformer, so that the reliability of the main transformer to low switch system is improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of power electronics technology, and in particular to a power supply method, device, equipment and medium for a main transformer low-voltage switch system. Background Art

[0002] For the Guangdong power grid and the Pearl River Delta region, which is the load center of the entire Southern Power Grid, the current value of the main transformer low-voltage switch is large due to the heavy load, often approaching or even exceeding the set safety limit, causing the switch cabinet to heat up, requiring power restriction or load transfer, resulting in short-term power outages for users.

[0003] The current of the main transformer low-voltage switch is the vector sum of active current and reactive current. The active current divided by the current of the main transformer low-voltage switch is the power factor (power factor is also equal to active power divided by apparent power, and apparent power is the vector sum of active power and reactive power). The power factor is the effective power supply capacity of the load. Failure to fully tap the power factor will lead to excessive current. In order to improve the power factor by switching capacitor groups and reactor groups, the bus voltage of the busbar will exceed the limit. The voltage can be adjusted by on-load tap-changing transformers as an auxiliary means. However, when the current of the main transformer low-voltage switch exceeds a certain value, the voltage is adjusted by on-load tap-changing transformers, which poses a safety hazard to the internal insulation of the transformer, forming a contradiction between balancing reactive current to reduce the current of the main transformer low-voltage switch and voltage regulation. Summary of the invention

[0004] The present invention provides a power supply method, device, equipment and medium for a main transformer low-voltage switch system. By real-time monitoring of the load information of the main transformer low-voltage switch, the reactive power of the main transformer low-voltage switch system is balanced in advance to improve the power factor of the main transformer low-voltage switch system. At the same time, the bus voltage of the bus is adjusted within a first range through an on-load tap-changing transformer, thereby improving the reliability of the main transformer low-voltage switch system.

[0005] In a first aspect, an embodiment of the present invention provides a power supply method for a main transformer lower switch system, wherein the main transformer lower switch system comprises a main transformer lower switch, a busbar and an on-load tap-changing transformer; a reactive power regulation device is arranged on the busbar.

[0006] The power supply method comprises:

[0007] Acquire current current information of the main transformer low-voltage switch, and determine load information of the main transformer low-voltage switch according to a ratio of the current current information to safety current information of the main transformer low-voltage switch;

[0008] Comparing the load information with first safety threshold information and second safety threshold information, wherein both the first safety threshold information and the second safety threshold information are less than 1;

[0009] When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power of the main transformer low-voltage switch is adjusted by the reactive power regulation device to improve the power factor of the main transformer low-voltage switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer.

[0010] Optionally, after comparing the load information with the first safety threshold information and the second safety threshold information, the method further includes:

[0011] When the load information is greater than the second safety threshold information, the bus voltage of the bus is adjusted to be within a first range through the reactive power adjustment device.

[0012] Optionally, a feeder is also provided on the busbar;

[0013] The step of regulating the reactive power of the main transformer low-voltage switch by the reactive power regulating device comprises:

[0014] The reactive power of the main transformer low-voltage switch is Q1, the reactive power of the feeder is Q, and the reactive power provided by the reactive regulation device is Q2;

[0015] The reactive power of the main transformer low-voltage switch, the reactive power of the feeder and the reactive power provided by the reactive power regulation device satisfy the following conditions:

[0016] Q1=Q+Q2;

[0017] By adjusting the reactive power provided by the reactive power regulating device, the absolute value of the reactive power of the main transformer low-voltage switch is made closest to 0, so as to improve the power factor of the main transformer low-voltage switch system.

[0018] Optionally, the reactive power regulation device includes a capacitor and a reactor;

[0019] The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes:

[0020] When Q≤0, and Q1<0, if Q2>0, the capacitors that have not been put into operation are put into operation in order of small to large capacity, until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the remaining capacitors that have not been put into operation, or when there are no remaining capacitors that have not been put into operation, no capacitors will be put into operation, wherein 1 / 3≤M0≤1 / 2;

[0021] When Q≤0 and Q1<0, if Q2<0, all reactors in operation will be shut down.

[0022] Optionally, the reactive power regulation device includes a capacitor and a reactor;

[0023] The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes:

[0024] When Q≤0 and Q1>0, then Q2>0, and the capacitors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation, and then the withdrawal of the capacitors is stopped, wherein 1 / 2<M1≤2 / 3.

[0025] Optionally, the reactive power regulation device includes a capacitor and a reactor;

[0026] The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes:

[0027] When Q>0, and Q1>0, if Q2<0, the reactors that are not put into operation are put into operation in order from large to small capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that are not put into operation, no more reactors are put into operation, wherein 1 / 2<M1≤2 / 3;

[0028] When Q>0, and Q1>0, if Q2>0, the capacitors that have been put into operation are withdrawn, and the reactors that have not been put into operation are put into operation in order from small to large capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the reactor that has not been put into operation, no resistors are put into operation, wherein 1 / 3≤M0≤1 / 2.

[0029] Optionally, the reactive power regulation device includes a capacitor and a reactor;

[0030] The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes:

[0031] When Q>0 and Q1<0, then Q2<0, and the reactors that have been put into operation will be withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have been put into operation, and then the reactor withdrawal will be stopped, where 1 / 2<M1≤2 / 3.

[0032] In a second aspect, an embodiment of the present invention further provides a power supply device for a main transformer low-voltage switch system. The power supply device comprises:

[0033] An acquisition module, used for acquiring current current information of the main transformer low-voltage switch, and determining load information of the main transformer low-voltage switch according to a ratio of the current current information to safety current information of the main transformer low-voltage switch;

[0034] A comparison module, configured to compare the load information with first safety threshold information and second safety threshold information, wherein both the first safety threshold information and the second safety threshold information are less than 1;

[0035] The regulation module is used to regulate the reactive power of the main transformer low-voltage switch through the reactive regulation device when the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, so as to improve the power factor of the main transformer low-voltage switch system, and regulate the bus voltage of the bus within the first range through the on-load tap-changing transformer.

[0036] In a third aspect, an embodiment of the present invention further provides a power supply device, the power supply device comprising one or more processors and a storage device, the storage device being used to store one or more programs, when the one or more programs are executed by the one or more processors, the one or more processors implement the power supply method described in any embodiment of the present invention.

[0037] In a fourth aspect, an embodiment of the present invention further provides a storage medium on which a computer program is stored, and when the computer program is executed by a processor, any power supply method described in the present invention is implemented.

[0038] The embodiment of the present invention obtains the current current information of the main transformer low-change switch, and determines the load information of the main transformer low-change switch according to the ratio of the current current information to the safety current information of the main transformer low-change switch. The load information is compared with the first safety threshold information and the second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1. When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power of the main transformer low-change switch is adjusted by the reactive power adjustment device to improve the power factor of the main transformer low-change switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer. In this way, by real-time monitoring of the load information of the main transformer low-change switch, the reactive power of the main transformer low-change switch system is balanced in advance within the interval of the first safety threshold information and the second safety threshold information to improve the power factor of the main transformer low-change switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer, which solves the problem of not being able to simultaneously improve the load power supply capacity of the main transformer low-change switch and adjust the bus voltage, and improves the reliability of the main transformer low-change switch system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flow chart of a power supply method for a main transformer low-voltage switch system provided in Embodiment 1 of the present invention;

[0040] Figure 2 is a flow chart of another power supply method for a main transformer low-voltage switch system provided in Embodiment 2 of the present invention;

[0041] Figure 3 It is a structural schematic diagram of a power supply device of a main transformer low-voltage switch system provided in Embodiment 3 of the present invention;

[0042] Figure 4 A schematic diagram of the structure of a power supply device provided in Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] Embodiment 1

[0046] Figure 1 This is a flow chart of a power supply method for a main transformer low-voltage switch system provided in Embodiment 1 of the present invention. This embodiment is applicable to the case where the load rate of the main transformer low-voltage switch is monitored. The method can be executed by the power supply device provided in the embodiment of the present invention, and the device can be implemented in software and / or hardware. The device can be configured in the power supply equipment provided in the embodiment of the present invention.

[0047] See also Figure 1 The power supply method of the main transformer low-voltage switch system includes:

[0048] S110, obtaining current current information of the main transformer lower switch, and determining load information of the main transformer lower switch according to a ratio of the current current information to the safety current information of the main transformer lower switch.

[0049] Specifically, the main transformer low-voltage switch system includes a main transformer low-voltage switch, a busbar and an on-load tap-changing transformer. Among them, the main transformer low-voltage switch is a low-voltage side switch of the main transformer. In the power system, the function of the main transformer is to convert high voltage electricity into low voltage electricity for use by equipment of different voltage levels. The low-voltage side switch of the main transformer is a key device connecting the main transformer and the low-voltage power grid. Its main functions include controlling the on and off of the current, isolating the circuit and providing protection in case of faults. The main transformer low-voltage switch is electrically connected to the busbar. A reactive power regulating device and a feeder are arranged on the busbar. The reactive power regulating device is used to provide reactive power to the main transformer low-voltage switch system or absorb reactive power. The main transformer low-voltage switch can transmit reactive power to the main transformer low-voltage switch system, or the main transformer low-voltage switch system can transmit reactive power to the main transformer low-voltage switch. The feeder can consume the reactive power of the main transformer low-voltage switch system, or the feeder can also transmit reactive power to the main transformer low-voltage switch system.

[0050] Since the main transformer low-voltage switch is connected to the busbar and the reactive power regulation device and feeder located on the busbar, the load of the main transformer low-voltage switch is heavy, that is, the power factor of the main transformer low-voltage switch is low. Among them, the power factor can be understood as the effective power supply capacity of the load. If the power factor is low, the effective power supply capacity of the load is not fully tapped, resulting in excessive current. For this reason, the reactive power regulation device is used to provide reactive power or absorb reactive power to adjust the power factor and balance the reactive power, thereby achieving the effect of reducing the current. However, in the process of adjusting the power factor, the current information of the main transformer low-voltage switch will exceed the regulation current of the on-load tap-changing transformer, resulting in the inability to adjust the bus voltage of the busbar through the on-load tap-changing transformer.

[0051] It can be understood that in the process of balancing reactive power through the reactive power regulating device, the reduction of the total current (current information of the main transformer low-voltage switch) is a reduction relative to the current active power state. Specifically, the current information of the main transformer low-voltage switch is the vector sum of the current of active power and the current of reactive power, wherein the current of active power is constantly changing with the power consumption at different times, and the total current cannot be reduced by adjusting the current of active power, but the total current is reduced by adjusting the current of reactive power through the reactive regulating device. Since the current of active power is changing, the total current after the adjustment and reduction in the morning will still be greater than the total current after the adjustment and reduction in the afternoon. Therefore, the reduction of the total current (current information of the main transformer low-voltage switch) is a reduction relative to the current active power state, rather than a reduction under any circumstances.

[0052] To this end, the embodiment of the present invention obtains the current current information of the main transformer low-voltage switch in real time, and determines the safety current information of the main transformer low-voltage switch. Among them, the safety current information can be understood as the regulating current of the on-load tap-changing transformer, that is, if the current current information exceeds the safety current information, the on-load tap-changing transformer is locked, and the bus voltage of the bus cannot be adjusted by the on-load tap-changing transformer. And according to the ratio of the current current information and the safety current information, the load information of the main transformer low-voltage switch is determined, and the proximity of the current current information to the safety current information is determined by the load information.

[0053] S120: Compare the load information with the first safety threshold information and the second safety threshold information.

[0054] Specifically, the first safety threshold information and the second safety threshold information are both pre-set, the first safety threshold information is less than the second safety threshold information, and the first safety threshold information and the second safety threshold information are both less than 1. Exemplarily, the load information of the main transformer low-voltage switch is A, the first safety threshold information is B1, and the second safety threshold information is B2. Then the range of the first safety threshold information B1 can be 0.75≤B1≥0.8, and the range of the second safety threshold information B2 can be 0.85≤B2≤0.9. The load information A represents the proximity of the current current information to the safety current information, that is, the closer the load information A is to 1, the closer the current current information is to the safety current information. Then the load information is compared with the first safety threshold information and the second safety threshold information, and the power factor and bus voltage are adjusted according to the final comparison result.

[0055] S130. When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power of the main transformer low-voltage switch is adjusted by the reactive power adjustment device to improve the power factor of the main transformer low-voltage switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer.

[0056] Exemplarily, since the range of the first safety threshold information B1 can be 0.75≤B1≥0.8, the range of the second safety threshold information B2 can be 0.85≤B2≤0.9. Furthermore, when the load information is greater than or equal to the first safety threshold information B1, and less than or equal to the second safety threshold information B2, that is, 0.75≤A≤0.9, it indicates that the load of the main transformer low-voltage switch is heavy, and there is a tendency to lock the on-load tap-changing transformer, and it is necessary to adjust in advance. At this time, the reactive power regulation device is used to provide reactive power to the main transformer low-voltage switch system or absorb reactive power to improve the power factor of the main transformer low-voltage switch system, and the bus voltage of the bus is adjusted to the first range through the on-load tap-changing transformer. Among them, when the bus is a 10KV bus, the first range can be 10.0KV to 10.7KV. In one embodiment, in order to ensure voltage stability in accordance with the peak period, the first range can also be 10.3KV to 10.5KV. In this way, by real-time monitoring of the load information of the main transformer lowering switch, the reactive power of the main transformer lowering switch system is balanced in advance within the interval of the first safety threshold information and the second safety threshold information to improve the power factor of the main transformer lowering switch system. At the same time, the bus voltage of the bus is adjusted within the first range through the on-load tap-changing transformer, which solves the problem of not being able to simultaneously improve the load power supply capacity of the main transformer lowering switch and adjust the bus voltage, thereby improving the reliability of the main transformer lowering switch system.

[0057] It should be noted that when the load information is less than the first safety threshold range, it indicates that the current current information of the main transformer low-voltage switch is small. Even if the reactive power of the main transformer low-voltage switch is adjusted by the reactive power regulation device, the current current information will not exceed the safety current information, that is, the on-load tap-changing transformer will not be locked. The present invention does not limit the regulation method within this interval.

[0058] It should also be noted that when the load information is greater than the second safety threshold information, it means that after the reactive power of the main transformer low-voltage switch is adjusted by the reactive power regulating device, the current current information of the main transformer low-voltage switch will exceed the safety current information, that is, the on-load tap-changing transformer will be locked, and the bus voltage of the bus cannot be adjusted by the on-load tap-changing transformer. The bus voltage of the bus is adjusted by the reactive power regulating device within the first range. That is, the bus voltage of the bus is guaranteed to be qualified first, and the power factor of the main transformer low-voltage switch system is improved secondly.

[0059] In summary, the embodiment of the present invention obtains the current current information of the main transformer low-change switch, and determines the load information of the main transformer low-change switch according to the ratio of the current current information to the safety current information of the main transformer low-change switch. The load information is compared with the first safety threshold information and the second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1. And when the load information is greater than or equal to the first safety threshold information, and less than or equal to the second safety threshold information, the reactive power of the main transformer low-change switch is adjusted by the reactive adjustment device to improve the power factor of the main transformer low-change switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer. In this way, by real-time monitoring of the load information of the main transformer low-change switch, the reactive power of the main transformer low-change switch system is balanced in advance within the interval of the first safety threshold information and the second safety threshold information to improve the power factor of the main transformer low-change switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer, which solves the problem of not being able to simultaneously improve the load power supply capacity of the main transformer low-change switch and adjust the bus voltage, and improves the reliability of the main transformer low-change switch system.

[0060] Embodiment 2

[0061] Figure 2 FIG. 1 is a flow chart of another power supply method for a main transformer low-voltage switch system provided in Embodiment 2 of the present invention. Figure 2 , the power supply method comprises:

[0062] S210, obtaining current current information of the main transformer lower switch, and determining load information of the main transformer lower switch according to a ratio of the current current information to the safety current information of the main transformer lower switch.

[0063] S220: Compare the load information with the first safety threshold information and the second safety threshold information.

[0064] S230. When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power provided by the reactive adjustment device is adjusted so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0, so as to improve the power factor of the main transformer low-voltage switch system, and adjust the bus voltage of the bus within the first range through the on-load tap-changing transformer.

[0065] Specifically, let the reactive power of the main transformer low-voltage switch be Q1, the reactive power of the feeder be Q, and the reactive power provided by the reactive regulation device be Q2. The reactive power of the main transformer low-voltage switch, the reactive power of the feeder, and the reactive power provided by the reactive regulation device satisfy: Q1=Q+Q2. Among them, Q≤0 can be understood as the feeder consuming the reactive power of the main transformer low-voltage switch system, and Q>0 can be understood as the feeder delivering reactive power to the main transformer low-voltage switch system. Q1<0 can be understood as the main transformer low-voltage switch delivering reactive power to the main transformer low-voltage switch system (busbar), and Q1>0 can be understood as the main transformer low-voltage switch system (busbar) delivering reactive power to the main transformer low-voltage switch. The reactive regulation device includes capacitors and reactors, and when Q2<0, it indicates that the reactor is currently put into operation, and when Q2>0, it indicates that the capacitor is currently put into operation. Furthermore, when the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the power factor of the main transformer low-voltage switch system can be improved according to the positive and negative conditions of the reactive power Q1 of the main transformer low-voltage switch, the reactive power Q of the feeder, and the reactive power Q2 provided by the reactive regulation device.

[0066] Exemplarily, when Q≤0 and Q1<0, if Q2>0, the capacitors that have not been put into operation are put into operation in order from small to large capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the remaining capacitors that have not been put into operation, or when there are no remaining capacitors that have not been put into operation, no capacitors will be put into operation, wherein 1 / 3≤M0≤1 / 2.

[0067] Specifically, when Q≤0 and Q1<0, that is, the feeder consumes the reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits reactive power to the main transformer low-voltage switch system (busbar), if Q2>0, it indicates that the capacitor has been put into operation at this time. For example, let Q=﹣10, Q1=﹣6, indicating that the feeder consumes 10 units of reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits 6 units of reactive power to the main transformer low-voltage switch system. According to Q1=Q+Q2, it can be known that the reactive power regulation device needs to transmit 4 units of reactive power to the main transformer low-voltage switch system to balance the reactive power (-6=-10+4). In other words, at this time, the main transformer low-voltage switch system has been put into operation with a total capacity of 4 units of capacitors. In order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. In this way, capacitors can continue to be added to the system. When Q remains unchanged, it is equivalent to reducing the absolute value of Q1, so that Q1 is close to 0. Exemplarily, when Q≤0, Q1<0, and Q2>0, the capacitors that have not been put into operation are put into operation in order from small to large capacity, until the absolute value of the reactive power of the main transformer low-power switch is less than M0 times the minimum capacity of the remaining capacitors that have not been put into operation, or when there are no remaining capacitors that have not been put into operation, no capacitors are put into operation, wherein 1 / 3≤M0≤1 / 2. For example, the capacities of the capacitors that have not been put into operation are 2, 3, and 4, respectively, from small to large. After the capacitors with capacities of 2 and 4 are put into operation respectively, Q1 becomes 0 (-6+2+4=-10+4+2+4). At this time, the absolute value of Q1 (0) is less than M0 times (4×1 / 2) the minimum capacity of the remaining capacitors that have not been put into operation, and no capacitors are put into operation, so that the reactive power of the main transformer low-power switch that is finally adjusted is close to 0, and the power factor of the main transformer low-power switch system is improved.

[0068] In yet another embodiment, when Q≤0 and Q1<0, all reactors that have been put into operation are shut down.

[0069] Specifically, when Q≤0 and Q1<0, that is, the feeder consumes the reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits reactive power to the main transformer low-voltage switch system (busbar), if Q2<0, it indicates that the reactor has been put into operation at this time. For example, if Q=-1, Q1=-6 indicates that the feeder consumes 1 unit of reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits 6 units of reactive power to the main transformer low-voltage switch system. According to Q1=Q+Q2, it can be known that the reactive power regulation device needs to absorb 5 units of reactive power of the main transformer low-voltage switch system to balance the reactive power (-6=-1-5). In other words, at this time, the main transformer low-voltage switch system has put into operation a reactor with a total capacity of 5 units. In order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. In this way, the reactor can be withdrawn from the system. Exemplarily, when Q≤0, Q1<0, and Q2<0, all reactors that have been put into operation are withdrawn. For example, the capacity of the reactors that have been put into operation is 5. After withdrawing all the reactors that have been put into operation, Q1 becomes -1 (-6+5=-2-4+5), so that the reactive power Q1 of the main transformer low-voltage switch that is finally adjusted is close to 0, thereby improving the power factor of the main transformer low-voltage switch system.

[0070] It should be noted that in this embodiment, after all the reactors that have been put into operation are shut down, the absolute value of Q1 is still much greater than 0. At this time, the absolute value of Q1 can be further reduced by adding capacitors until the absolute value of Q1 is close to 0.

[0071] Exemplarily, in another embodiment, when Q≤0 and Q1>0, then Q2>0, the capacitors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation, and the withdrawal of the capacitors is stopped, wherein 1 / 2≤M1≤2 / 3.

[0072] Specifically, when Q≤0, and Q1>0, the feeder consumes the reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch system (busbar) transmits reactive power to the main transformer low-voltage switch. At this time, according to Q1=Q+Q2, it can be seen that only when Q2 is positive can the reactive power balance be guaranteed. For example, let Q=-4, Q1=6, indicating that the feeder consumes 4 units of reactive power of the main transformer low-voltage switch system, and the main transformer low-voltage switch system transmits 6 units of reactive power to the main transformer low-voltage switch. According to Q1=Q+Q2, it can be seen that the reactive power regulation device needs to transmit 10 units of reactive power to the main transformer low-voltage switch system to balance the reactive power (6=-4+10). In other words, at this time, the main transformer low-voltage switch system has been put into operation with a total capacity of 10 units of capacitors. In order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. In this way, the capacitors that have been put into operation can be withdrawn. When Q remains unchanged, it is equivalent to reducing the absolute value of Q1, so that Q1 is close to 0. Exemplarily, when Q≤0, Q1>0, and Q2>0, the capacitors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation, and the withdrawal of the capacitors is stopped, wherein 1 / 2<M1≤2 / 3. For example, the capacities of the capacitors that have been put into operation are 4, 3, 2, and 1, respectively, from large to small. After withdrawing the capacitors with a capacity of 4 and a capacity of 3, Q1 becomes -1 (6-4-3=-4+10-4-3). At this time, when the absolute value (1) of Q1 is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation (2×2 / 3), the capacitors are no longer withdrawn, so that the reactive power of the main transformer low-voltage switch that is finally adjusted is close to 0, and the power factor of the main transformer low-voltage switch system is improved.

[0073] In another embodiment, when Q>0 and Q1>0, if Q2<0, the reactors that have not been put into operation are put into operation in order from large to small capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have not been put into operation, no more reactors are put into operation, wherein 1 / 2<M1≤2 / 3.

[0074] Specifically, when Q>0, and Q1>0, that is, the feeder transmits reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch system (busbar) transmits reactive power to the main transformer low-voltage switch, if Q2<0, it indicates that the reactor has been put into operation at this time. For example, suppose Q=10, Q1=6, indicating that the feeder transmits 10 units of reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch system (busbar) transmits 6 units of reactive power to the main transformer low-voltage switch. According to Q1=Q+Q2, it can be known that the reactive power regulation device needs to absorb 4 units of reactive power of the main transformer low-voltage switch system to balance the reactive power (6=10-4). In other words, at this time, the main transformer low-voltage switch system has put into operation a reactor with a total capacity of 4 units, and in order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. In this way, reactors can continue to be added to the system. When Q remains unchanged, it is equivalent to reducing the absolute value of Q1, so that Q1 is close to 0. Exemplarily, when Q>0 and Q1>0, if Q2<0, the reactors that are not put into operation are put into operation in order from large to small capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that are not put into operation, no more reactors are put into operation, where 1 / 2<M1≤2 / 3. For example, the capacities of the reactors that are not put into operation are 4, 3, and 2, respectively, from large to small. After the reactors with capacities of 4 and 3 are put into operation respectively, Q1 becomes -1 (6-4-3=10-4-4-3). At this time, Q1 is less than 0, and the absolute value of Q1 (1) is less than M1 times (2×2 / 3) of the maximum capacity of the remaining reactors that have not been put into operation. Then, no more reactors are put into operation. In this way, the reactive power of the main transformer low-voltage switch is finally adjusted to be close to 0, thereby improving the power factor of the main transformer low-voltage switch system.

[0075] Exemplarily, in another embodiment, when Q>0 and Q1>0, if Q2>0, the capacitors that have been put into operation are withdrawn, and the reactors that have not been put into operation are put into operation in order from small to large capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the reactor that has not been put into operation, the resistor is no longer put into operation, wherein 1 / 3≤M0≤1 / 2.

[0076] Specifically, when Q>0 and Q1>0, that is, the feeder transmits reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch system (busbar) transmits reactive power to the main transformer low-voltage switch, if Q2>0, it indicates that the capacitor has been put into operation at this time. For example, let Q=6, Q1=10, indicating that the feeder transmits 6 units of reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch system (busbar) transmits 10 units of reactive power to the main transformer low-voltage switch. According to Q1=Q+Q2, it can be known that the reactive power regulation device needs to transmit 4 units of reactive power to the main transformer low-voltage switch system to balance the reactive power (10=6+4). In other words, at this time, the main transformer low-voltage switch system has put into operation a capacitor with a total capacity of 4 units, and in order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. Exemplarily, when Q>0, and Q1>0, if Q2>0, the capacitors that have been put into operation are withdrawn. At this time, the main transformer low-voltage switch system (busbar) transmits 6 units of reactive power to the main transformer low-voltage switch (i.e., Q1=10-4=6). It can be seen that the absolute value of Q1 is still far from 0 at this time. Then, the reactors that have not been put into operation are put into operation in order from small to large capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the remaining reactors that have not been put into operation, the reactors are no longer put into operation, where 1 / 3≤M0≤1 / 2. For example, after withdrawing the capacitors, the capacities of the reactors that have not been put into operation are 3, 4, and 5 from small to large. After the reactors with capacities of 3 and 4 are put into operation respectively, Q1 becomes -1 (10-4-3-4=6+4-4-3-4). At this time, Q1 is less than 0, and the absolute value of Q1 (1) is less than M0 times (5×1 / 3) of the minimum capacity of the remaining reactors that have not been put into operation. Then, no more reactors are put into operation, so that the reactive power of the main transformer low-voltage switch is finally adjusted close to 0, thereby improving the power factor of the main transformer low-voltage switch system.

[0077] In another embodiment, when Q>0 and Q1<0, then Q2<0, and the reactors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have been put into operation, and then the withdrawal of capacitors is stopped, wherein 1 / 2<M1≤2 / 3.

[0078] Specifically, when Q>0 and Q1<0, that is, the feeder transmits reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits reactive power to the main transformer low-voltage switch system (busbar), Q2 can only be less than 0, that is, only the reactor can be put into operation. For example, suppose Q=6, Q1=-4, indicating that the feeder transmits 6 units of reactive power to the main transformer low-voltage switch system, and the main transformer low-voltage switch transmits 4 units of reactive power to the main transformer low-voltage switch system (busbar). According to Q1=Q+Q2, it can be known that the reactive power regulation device needs to absorb 10 units of reactive power of the main transformer low-voltage switch system to balance the reactive power (-4=6-10). In other words, at this time, the main transformer low-voltage switch system has put into operation a reactor with a total capacity of 10 units, and in order to improve the power factor of the main transformer low-voltage switch system, it is necessary to make the reactive power of the main transformer low-voltage switch close to 0, that is, the absolute value of Q1 is close to 0. Exemplarily, when Q>0, and Q1<0, then Q2<0, and then the reactors that have been put into operation are withdrawn in order from large to small capacity, until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have been put into operation, and then the reactor is stopped from being withdrawn, wherein 1 / 2<M1≤2 / 3. For example, the capacities of the reactors that have been put into operation are 4, 3, 2, and 1 from large to small. After withdrawing the reactor with a capacity of 4, Q1 becomes 0 (-4+4=6-10+4). At this time, and the absolute value of Q1 (0) is less than M1 times (3×2 / 3) the maximum capacity of the remaining reactors that have been put into operation, the reactor is no longer withdrawn, so that the reactive power of the main transformer low-voltage switch that is finally adjusted is close to 0, thereby improving the power factor of the main transformer low-voltage switch system.

[0079] In summary, the embodiments of the present invention balance the reactive power of the main transformer lowering switch system in advance within the interval of the first safety threshold information and the second safety threshold information to improve the power factor of the main transformer lowering switch system by real-time monitoring of the load information of the main transformer lowering switch. At the same time, according to the reactive power of the main transformer lowering switch, the reactive power of the feeder and the positive and negative conditions of the reactive power provided by the reactive regulation device, different methods are adopted to make the reactive power of the main transformer lowering switch finally adjusted close to 0, thereby improving the power factor of the main transformer lowering switch system and further improving the reliability of the main transformer lowering switch system.

[0080] Embodiment 3

[0081] Figure 3 Schematic diagram of the structure of a power supply device of a main transformer low-voltage switch system provided by the third embodiment of the present invention. Figure 3 This embodiment is applicable to monitoring the load rate of the main transformer low-voltage switch. The specific structure of the power supply device is as follows:

[0082] The acquisition module 100 is used to acquire the current current information of the main transformer lower switch, and determine the load information of the main transformer lower switch according to the ratio of the current current information to the safety current information of the main transformer lower switch.

[0083] The comparison module 200 is used to compare the load information with the first safety threshold information and the second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1.

[0084] The regulation module 300 is used to adjust the reactive power of the main transformer low-voltage switch through a reactive regulation device when the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, so as to improve the power factor of the main transformer low-voltage switch system, and adjust the bus voltage of the bus within the first range through the on-load tap-changing transformer.

[0085] The regulating module 300 is further configured to regulate the bus voltage of the bus within a first range through a reactive regulating device when the load information is greater than the second safety threshold information.

[0086] The busbar is also provided with a feeder, the reactive power of the main transformer low-voltage switch is Q1, the reactive power of the feeder is Q, and the reactive power provided by the reactive regulation device is Q2;

[0087] The reactive power of the main transformer low-voltage switch, the reactive power of the feeder and the reactive power provided by the reactive regulation device meet the following requirements:

[0088] Q1=Q+Q2;

[0089] The regulating module 300 is also used to make the absolute value of the reactive power of the main transformer lower switch closest to 0 by regulating the reactive power provided by the reactive regulating device, so as to improve the power factor of the main transformer lower switch system.

[0090] The adjustment module 300 includes a first adjustment unit, a second adjustment unit, a third adjustment unit, a fourth adjustment unit, a fifth adjustment unit and a sixth adjustment unit.

[0091] The first regulating unit is used for, when Q≤0 and Q1<0, if Q2>0, to put the capacitors that have not been put into operation into operation in ascending order of capacity, until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the remaining capacitors that have not been put into operation, or when there are no remaining capacitors that have not been put into operation, no capacitors will be put into operation, wherein 1 / 3≤M0≤1 / 2.

[0092] The second regulating unit is used for shutting down all reactors that have been put into operation when Q≤0 and Q1<0 and if Q2<0.

[0093] The third regulating unit is used for, when Q≤0 and Q1>0, then Q2>0, to withdraw the capacitors that have been put into operation in order from large to small capacity, until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation, and then stop withdrawing the capacitors, wherein 1 / 2<M1≤2 / 3.

[0094] The fourth regulating unit is used for, when Q>0 and Q1>0, if Q2<0, to put the reactors that have not been put into operation into operation in order from large to small capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have not been put into operation, no more reactors will be put into operation, wherein 1 / 2<M1≤2 / 3.

[0095] The fifth regulating unit is used for withdrawing the capacitors that have been put into operation if Q2>0 when Q>0 and Q1>0, and putting the reactors that have not been put into operation into operation in order from small to large capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the reactor that has not been put into operation, the resistor is no longer put into operation, wherein 1 / 3≤M0≤1 / 2.

[0096] The sixth regulating unit is used for when Q>0 and Q1<0, then Q2<0, then the reactors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have been put into operation, and then the withdrawal of the reactors is stopped, wherein 1 / 2<M1≤2 / 3.

[0097] In summary, the acquisition module in the embodiment of the present invention is used to obtain the current current information of the main transformer low-voltage switch, and determine the load information of the main transformer low-voltage switch according to the ratio of the current current information to the safety current information of the main transformer low-voltage switch. The comparison module is used to compare the load information with the first safety threshold information and the second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1. The adjustment module is used to adjust the reactive power of the main transformer low-voltage switch through the reactive adjustment device when the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, so as to improve the power factor of the main transformer low-voltage switch system, and adjust the bus voltage of the bus through the on-load tap-changing transformer within the first range. In this way, by real-time monitoring of the load information of the main transformer lowering switch, the reactive power of the main transformer lowering switch system is balanced in advance within the interval of the first safety threshold information and the second safety threshold information to improve the power factor of the main transformer lowering switch system. At the same time, the bus voltage of the bus is adjusted within the first range through the on-load tap-changing transformer, which solves the problem of not being able to simultaneously improve the load power supply capacity of the main transformer lowering switch and adjust the bus voltage, thereby improving the reliability of the main transformer lowering switch system.

[0098] Embodiment 4

[0099] Figure 4 A schematic diagram of the structure of a power supply device provided for Embodiment 4 of the present invention, the power supply device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The power supply device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0100] like Figure 4 As shown, the power supply device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the power supply device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. The input / output (I / O) interface 15 is also connected to the bus 14.

[0101] A number of components in the power supply device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the power supply device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0102] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 performs the various methods and processes described above.

[0103] In some embodiments, the power supply method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the power supply device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the compensation method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the power supply method in any other suitable manner (e.g., by means of firmware).

[0104] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0105] Embodiment 5

[0106] Embodiment 5 of the present invention further provides a storage medium including computer executable instructions. When the computer executable instructions are executed by a computer processor, they are used to execute a power supply method for a main transformer low-voltage switch system. The power supply method includes:

[0107] Obtaining current information of the main transformer lower switch, and determining load information of the main transformer lower switch according to the ratio of the current current information to the safety current information of the main transformer lower switch;

[0108] Comparing the load information with the first safety threshold information and the second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1;

[0109] When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power of the main transformer low-voltage switch is adjusted by the reactive power adjustment device to improve the power factor of the main transformer low-voltage switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer.

[0110] Of course, the computer executable instructions of a storage medium including computer executable instructions provided by an embodiment of the present invention are not limited to the operations of the method described above, but can also execute related operations in the power supply method provided by any embodiment of the present invention.

[0111] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0112] It is worth noting that in the embodiment of the above-mentioned search device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0113] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A power supply method for a main transformer low-voltage switch system, characterized in that: The main transformer low-voltage switch system includes a main transformer low-voltage switch, a busbar and an on-load tap-changing transformer; a reactive power regulating device is arranged on the busbar; The power supply method comprises: Acquire current current information of the main transformer low-voltage switch, and determine load information of the main transformer low-voltage switch according to a ratio of the current current information to safety current information of the main transformer low-voltage switch; Comparing the load information with first safety threshold information and second safety threshold information, wherein the first safety threshold information and the second safety threshold information are both less than 1; When the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, the reactive power of the main transformer low-voltage switch is adjusted by the reactive power regulation device to improve the power factor of the main transformer low-voltage switch system, and the bus voltage of the bus is adjusted within the first range by the on-load tap-changing transformer.

2. The power supply method according to claim 1, characterized in that: After comparing the load information with the first safety threshold information and the second safety threshold information, the method further includes: When the load information is greater than the second safety threshold information, the bus voltage of the bus is adjusted to be within a first range through the reactive power adjustment device.

3. The power supply method according to claim 1, characterized in that: The busbar is also provided with a feeder; The step of regulating the reactive power of the main transformer low-voltage switch by the reactive power regulating device comprises: The reactive power of the main transformer low-voltage switch is Q1, the reactive power of the feeder is Q, and the reactive power provided by the reactive regulation device is Q2; The reactive power of the main transformer low-voltage switch, the reactive power of the feeder and the reactive power provided by the reactive power regulation device satisfy the following conditions: Q1=Q+Q2; By adjusting the reactive power provided by the reactive power regulating device, the absolute value of the reactive power of the main transformer low-voltage switch is made closest to 0, so as to improve the power factor of the main transformer low-voltage switch system.

4. The power supply method according to claim 3, characterized in that: The reactive power regulating device comprises a capacitor and a reactor; The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes: When Q≤0, and Q1<0, if Q2>0, the capacitors that have not been put into operation are put into operation in order of small to large capacity, until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the remaining capacitors that have not been put into operation, or when there are no remaining capacitors that have not been put into operation, no capacitors will be put into operation, wherein 1 / 3≤M0≤1 / 2; When Q≤0 and Q1<0, if Q2<0, all reactors in operation will be shut down.

5. The power supply method according to claim 3, characterized in that: The reactive power regulating device comprises a capacitor and a reactor; The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes: When Q≤0 and Q1>0, then Q2>0, and the capacitors that have been put into operation are withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining capacitors that have been put into operation, and then the withdrawal of the capacitors is stopped, wherein 1 / 2<M1≤2 / 3.

6. The power supply method according to claim 3, characterized in that: The reactive power regulating device comprises a capacitor and a reactor; The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes: When Q>0, and Q1>0, if Q2<0, the reactors that are not put into operation are put into operation in order from large to small capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that are not put into operation, no more reactors are put into operation, wherein 1 / 2<M1≤2 / 3; When Q>0, and Q1>0, if Q2>0, the capacitors that have been put into operation are withdrawn, and the reactors that have not been put into operation are put into operation in order from small to large capacity, so that the reactive power of the main transformer low-voltage switch is less than 0, and until the absolute value of the reactive power of the main transformer low-voltage switch is less than M0 times the minimum capacity of the reactor that has not been put into operation, no resistors are put into operation, wherein 1 / 3≤M0≤1 / 2.

7. The power supply method according to claim 3, characterized in that: The reactive power regulating device comprises a capacitor and a reactor; The step of adjusting the reactive power provided by the reactive adjustment device so that the absolute value of the reactive power of the main transformer low-voltage switch is closest to 0 includes: When Q>0 and Q1<0, then Q2<0, and the reactors that have been put into operation will be withdrawn in order from large to small capacity until the absolute value of the reactive power of the main transformer low-voltage switch is less than M1 times the maximum capacity of the remaining reactors that have been put into operation, and then the reactor withdrawal will be stopped, where 1 / 2<M1≤2 / 3.

8. A power supply device for a main transformer low-voltage switch system, the main transformer low-voltage switch system comprising a main transformer low-voltage switch, a busbar and an on-load tap-changing transformer; a reactive power regulating device is arranged on the busbar; The power supply device comprises: An acquisition module, used for acquiring current current information of the main transformer low-voltage switch, and determining load information of the main transformer low-voltage switch according to a ratio of the current current information to safety current information of the main transformer low-voltage switch; A comparison module, configured to compare the load information with first safety threshold information and second safety threshold information, wherein both the first safety threshold information and the second safety threshold information are less than 1; The regulation module is used to regulate the reactive power of the main transformer low-voltage switch through the reactive regulation device when the load information is greater than or equal to the first safety threshold information and less than or equal to the second safety threshold information, so as to improve the power factor of the main transformer low-voltage switch system, and regulate the bus voltage of the bus within the first range through the on-load tap-changing transformer.

9. A power supply device, characterized in that: The power supply device comprises: one or more processors; a storage device for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors implement the power supply method according to any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the power supply method as described in any one of claims 1 to 7 is implemented.

Images