Hybrid static phase modifier system and electronic device

Abstract

The hybrid static phase modifier system and the electronic equipment provided by the embodiments of the present disclosure comprise a control device and a power compensation device; the power compensation device comprises high and low voltage modules combined in series as power chain links of the power compensation device and connected to corresponding phases in the power grid respectively, and is used to provide power compensation for the power grid; the control device collects power grid data, determines requirements according to the power grid data, and the high and low voltage modules in the power compensation device change switching states; the high and low voltage modules provide reactive power and / or active power for the power grid through the power compensation device. The phase modifier system provided by the present disclosure adopts a modular design, and through the combination of multiple high and low voltage modules, flexible configuration according to the requirements of the power grid can be realized; the number of high and low voltage modules in the power compensation device can be changed according to requirements; the phase modifier system does not contain mechanical devices, uses electrical energy storage elements to provide power compensation for the power grid, has fast response speed, and can provide reactive power and active power for the power grid.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of energy storage, and particularly relates to a hybrid static phase modifier system and an electronic device. BACKGROUND

[0002] With the development of high proportion of new energy access and extra-high voltage direct current transmission technology at the present stage, the characteristics of the power grid change significantly, voltage support is insufficient, reactive power reserve is reduced, and the like problems frequently occur, and threaten the safety and stability of the power grid operation. In view of this situation, the power compensation capacity of the power grid needs to be further improved. The traditional mechanical phase modifier adopts a mechanical structure, has large volume, low flexibility, slow response, and is difficult to adapt to the rapid development of the power grid at present. The static var compensator (SVC) can realize dynamic compensation and has fast response, but does not have an energy storage element and cannot provide active power support for the power grid. The static synchronous phase modifier based on super capacitor can realize active support by using super capacitor as an energy storage element, but the cost of super capacitor is relatively high compared with chemical battery; due to the rapid change of power demand in the application scene, the energy storage element is frequently charged and discharged, and if the chemical battery is used as the energy storage element, the battery life will be significantly reduced. In view of the above, there is an urgent need for a new compensation device which can quickly respond to reactive power of the power grid and provide active support, and has economy and durability. SUMMARY

[0003] Embodiments of the present disclosure provide a hybrid static phase modifier system and an electronic device to solve the shortcomings of low flexibility, slow response, inability to provide active support and poor economy of the existing compensation device.

[0004] Based on the above problems, in a first aspect, embodiments of the present disclosure provide a hybrid static phase modifier system, comprising: a control device and a power compensation device;

[0005] The power compensation device comprises a plurality of high-low voltage modules; the high-low voltage modules are combined in series to form power chain links of the power compensation device; the power chain links are connected in a preset connection mode and are respectively connected to corresponding phases in the power grid, and are used to provide power compensation for the power grid;

[0006] The control device is used to collect power grid data, determine power grid demand according to the power grid data, and send a control instruction to control the high-low voltage modules in the power compensation device to change the switch state;

[0007] The high-low voltage module is used to provide reactive power and / or active power to the power grid through the power compensation device according to the switch state.

[0008] In combination with the first aspect, in a possible implementation, the high-low voltage module comprises: a power module, a capacitor module, and a battery module.

[0009] The power module comprises a plurality of power semiconductor devices; the power semiconductor devices comprise: a switch tube and a diode.

[0010] An anode of the diode is connected to an emitter of the switch tube as an output end of the power semiconductor device, a cathode of the diode is connected to a collector of the switch tube as an input end of the power semiconductor device, and a gate of the switch tube receives the control instruction and controls on-off of the switch tube according to the control instruction.

[0011] The power module is connected to the capacitor module and the battery module respectively.

[0012] The capacitor module is configured to provide reactive power to a power grid.

[0013] The battery module is configured to provide active power to the power grid.

[0014] The power module is configured to provide the reactive power and / or the active power to the power grid by controlling on-off of the capacitor module and the battery module according to the switch state.

[0015] In combination with the first aspect, in a possible implementation, the power module comprises: a first power semiconductor device, a second power semiconductor device, a third power semiconductor device, a fourth power semiconductor device, a fifth power semiconductor device, and a sixth power semiconductor device.

[0016] An output end of the first power semiconductor device is connected to an input end of the second power semiconductor device as a first alternating current port of the high-low voltage module, and an input end of the first power semiconductor device is connected to one end of the capacitor module and an input end of the third power semiconductor device respectively.

[0017] An output end of the second power semiconductor device is connected to the other end of the capacitor module and an output end of the fourth power semiconductor device respectively.

[0018] An output end of the third power semiconductor device is connected to a positive electrode of the battery module and an input end of the fifth power semiconductor device respectively.

[0019] An input end of the fourth power semiconductor device is connected to a negative electrode of the battery module and an output end of the sixth power semiconductor device respectively.

[0020] An output end of the fifth power semiconductor device is connected to an input end of the sixth power semiconductor device as a second alternating current port of the high-low voltage module.

[0021] In combination with the first aspect, in a possible implementation, the power chain section includes a preset number of high-low voltage modules and an output reactor; the preset number is determined according to the reactive power demand of the power grid;

[0022] The first alternating current port of the high-low voltage module in the power chain section, except the last-stage high-low voltage module, is connected to the second alternating current port of another high-low voltage module, and the first alternating current port of the last-stage high-low voltage module is connected to the corresponding phase in the power grid through the output reactor;

[0023] In the power compensation device, any two power chain sections include the same number of high-low voltage modules.

[0024] In combination with the first aspect, in a possible implementation, the control device determines the power demand of the power grid according to the grid data, and determines the demand voltage of each phase in the power grid respectively;

[0025] In the case that the power grid demands reactive power, the control device determines the capacitor voltage of each high-low voltage module in the power chain section in each preset period, and determines at least one high-low voltage module as the first balancing module of the current period for each power chain section according to the difference between the capacitor voltage and the preset rated voltage; the switching state of the corresponding first balancing module is determined according to the current direction of the power grid, and the output voltage of the first balancing module is determined;

[0026] In the case that the power grid demands active power, the control device determines the battery capacity of each high-low voltage module in the power chain section in each preset period, and determines at least one high-low voltage module as the second balancing module of the current period for each power chain section according to the difference between the battery capacity and the preset battery capacity; the switching state of the corresponding second balancing module is determined according to the current direction of the power grid, and the output voltage of the second balancing module is determined.

[0027] In combination with the first aspect, in a possible implementation, in the case that a high-low voltage module in the power chain section is determined as the first balancing module, the control device determines the first reference voltage of the power chain section according to the demand voltage, the output voltage of the first balancing module and the number of high-low voltage modules in the power chain section, and determines the switching state of the high-low voltage module in the power chain section, except the first balancing module, according to the first reference voltage;

[0028] In the case that the first reference voltage is greater than a first threshold value, the high-low voltage module is determined as the first switching state;

[0029] In the case that the first reference voltage is less than a first threshold value and greater than a second threshold value, the high-low voltage module is determined as the second switching state or the third switching state.

[0030] In a case where the second reference voltage is greater than a first threshold value, the high-low voltage module is determined to be in a first switching state.

[0031] In combination with the first aspect, in a possible implementation, in a case where the high-low voltage module in the power chain segment is determined to be the second equalization module, the control device determines a second reference voltage of the power chain segment according to the demand voltage, an output voltage of the second equalization module, and a number of high-low voltage modules in the power chain segment, and determines switching states of the high-low voltage modules in the power chain segment except the second equalization module according to the second reference voltage.

[0032] In a case where the second reference voltage is greater than a first threshold value, the high-low voltage module is determined to be in a first switching state.

[0033] In a case where the second reference voltage is less than the first threshold value and greater than a third threshold value, the high-low voltage module is determined to be in a fifth switching state or a sixth switching state.

[0034] In a case where the second reference voltage is less than the third threshold value and greater than a fourth threshold value, the high-low voltage module is determined to be in a second switching state or a third switching state.

[0035] In a case where the second reference voltage is less than the fourth threshold value and greater than a second threshold value, the high-low voltage module is determined to be in a seventh switching state or an eighth switching state.

[0036] In a case where the second reference voltage is less than the second threshold value, the high-low voltage module is determined to be in a fourth switching state.

[0037] In combination with the first aspect, in a possible implementation, in a case where the high-low voltage module is in the first switching state, the first power semiconductor device, the fourth power semiconductor device, and the sixth power semiconductor device are turned on, the second power semiconductor device, the third power semiconductor device, and the fifth power semiconductor device are turned off, the battery module is disconnected, and the capacitor module is turned on.

[0038] In a case where the high-low voltage module is in the second switching state, the first power semiconductor device, the third power semiconductor device, and the fifth power semiconductor device are turned on, the second power semiconductor device, the fourth power semiconductor device, and the sixth power semiconductor device are turned off, and the battery module and the capacitor module are disconnected.

[0039] In a case where the high-low voltage module is in the third switching state, the first power semiconductor device, the third power semiconductor device, and the fifth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device, and the sixth power semiconductor device are turned on, and the battery module and the capacitor module are disconnected.

[0040] In the case that the high-low voltage module is in the fourth switch state, the first power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned off, the second power semiconductor device, the third power semiconductor device and the fifth power semiconductor device are turned on, the battery module is disconnected, and the capacitor module is turned on.

[0041] In combination with the first aspect, in a possible implementation, in the case that the high-low voltage module is in the fifth switch state, the first power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned on, the second power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned off, and the battery module and the capacitor module are turned on.

[0042] In the case that the high-low voltage module is in the sixth switch state, the first power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned on, the second power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned off, the battery module is turned on, and the capacitor module is disconnected.

[0043] In the case that the high-low voltage module is in the seventh switch state, the first power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned on, the battery module is turned on, and the capacitor module is disconnected.

[0044] In the case that the high-low voltage module is in the eighth switch state, the first power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned on, and the battery module and the capacitor module are turned on.

[0045] In combination with the first aspect, in a possible implementation, in the case that the grid demands active power, the control device determines the switch state of the high-low voltage module according to the current direction of the grid and the demand voltage of the grid.

[0046] In the case that the grid demands positive active power and the current direction is the first direction, the high-low voltage module is determined to be in one of the first switch state, the second switch state, the third switch state, the fourth switch state, the fifth switch state or the seventh switch state according to the output voltage of the corresponding power chain and the demand voltage.

[0047] in a case where the grid demand active power is positive and the current direction is the second direction, determining the high-low voltage module to be one of the first switching state, the second switching state, the third switching state, the fourth switching state, the sixth switching state or the eighth switching state according to the output voltage of the corresponding power chain and the demand voltage;

[0048] in a case where the grid demand active power is negative and the current direction is the second direction, determining the high-low voltage module to be one of the first switching state, the second switching state, the third switching state, the fourth switching state, the fifth switching state or the seventh switching state according to the output voltage of the corresponding power chain and the demand voltage;

[0049] in a case where the grid demand active power is negative and the current direction is the first direction, determining the high-low voltage module to be one of the first switching state, the second switching state, the third switching state, the fourth switching state, the sixth switching state or the eighth switching state according to the output voltage of the corresponding power chain and the demand voltage.

[0050] With reference to the first aspect, in a possible implementation, in a case where the current direction is the first direction and the capacitor voltage of the first equalization module is greater than the preset rated voltage, the switching state of the first equalization module is determined to be the fourth switching state;

[0051] in a case where the current direction is the second direction and the capacitor voltage of the first equalization module is greater than the preset rated voltage, the switching state of the first equalization module is determined to be the first switching state;

[0052] in a case where the current direction is the first direction and the capacitor voltage of the first equalization module is less than the preset rated voltage, the switching state of the first equalization module is determined to be the first switching state;

[0053] in a case where the current direction is the second direction and the capacitor voltage of the first equalization module is less than the preset rated voltage, the switching state of the first equalization module is determined to be the fourth switching state.

[0054] With reference to the first aspect, in a possible implementation, in a case where the current direction is the first direction and the battery power of the second equalization module is greater than the preset power, the switching state of the second equalization module is determined to be one of the fifth switching state or the seventh switching state;

[0055] in a case where the current direction is the first direction and the battery power of the second equalization module is less than the preset power, the switching state of the second equalization module is determined to be one of the sixth switching state or the eighth switching state;

[0056] determining that the switch state of the second equalization module is one of a fifth switch state or a seventh switch state in a case that the current direction is the second direction and the battery power of the second equalization module is less than the preset power;

[0057] determining that the switch state of the second equalization module is one of a sixth switch state or an eighth switch state in a case that the current direction is the second direction and the battery power of the second equalization module is greater than the preset power.

[0058] In a second aspect, the disclosure also provides an electronic device, comprising: the hybrid static phase modifier system of any one of the first aspect.

[0059] The beneficial effects of the embodiments of the disclosure include:

[0060] The hybrid static phase modifier system and the electronic device provided by the embodiments of the disclosure include: a control device and a power compensation device; the power compensation device includes a plurality of high-low voltage modules; the high-low voltage modules are combined in series as power chain links of the power compensation device; the power chain links are connected in a preset connection mode and are respectively connected to corresponding phases in the power grid, for providing power compensation for the power grid; the control device is used to collect power grid data, determine power grid demand according to the power grid data, and send a control instruction to control the high-low voltage modules in the power compensation device to change the switch state; the high-low voltage modules are used to provide reactive power and / or active power to the power grid through the power compensation device according to the switch state. The phase modifier system provided by the disclosure adopts a modular design, and through the combination of a plurality of high-low voltage modules, it can be flexibly configured according to the needs of the power grid; and the number of configurations of the high-low voltage modules in the power compensation device can be changed according to the needs. The phase modifier system does not contain mechanical devices, uses electrical energy storage elements to provide power compensation for the power grid, has fast response speed, and can provide reactive power and active power for the power grid. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 A structural schematic diagram of the hybrid static phase modifier system provided by the embodiments of the disclosure is shown in the figure;

[0062] Figure 2 A structural schematic diagram of the high-low voltage module provided by the embodiments of the disclosure is shown in the figure;

[0063] Figure 3 A structural schematic diagram of the power module provided by the embodiments of the disclosure is shown in the figure;

[0064] Figure 4 A structural schematic diagram of the power compensation device adopting a star connection mode provided by the embodiments of the disclosure is shown in the figure;

[0065] Figure 5 A basic operation logic flowchart of the phase modifier system provided by the embodiments of the disclosure is shown in the figure;

[0066] Figure 6 A carrier modulation strategy diagram of the phase modifier system during reactive power compensation provided by the embodiments of the present disclosure;

[0067] Figure 7 A carrier modulation strategy diagram of the phase modifier system during active power support provided by the embodiments of the present disclosure. DETAILED DESCRIPTION

[0068] The embodiments of the present disclosure provide a hybrid static phase modifier system and an electronic device. The preferred embodiments described herein are used to illustrate and explain the present disclosure, and are not used to limit the present disclosure. The embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0069] The embodiments of the present disclosure provide a hybrid static phase modifier system, as shown in the drawings, comprising a control device 1 and a power compensation device 2. Figure 1

[0070] The power compensation device 2 comprises a plurality of high-low voltage modules 21. The high-low voltage modules 21 are connected in series to form power chain links 22 of the power compensation device 2. The power chain links 22 are connected in a predetermined connection mode and are connected to corresponding phases in the power grid, respectively, for providing power compensation for the power grid.

[0071] The control device 1 is used to collect power grid data and determine power grid demand according to the power grid data, and send control instructions to control the high-low voltage modules 21 in the power compensation device 2 to change the switching state.

[0072] The high-low voltage module 21 is used to provide reactive power and / or active power to the power grid through the power compensation device 2 according to the switching state.

[0073] In the embodiments of the present disclosure, the phase modifier system is a device applied to a power system for power compensation, which can be arranged in a converter station of a direct current transmission, a new energy power generation station (for example, a wind power station and a photovoltaic power station, etc.) and other weak areas of the power grid, for suppressing power grid fluctuations and avoiding voltage instability.

[0074] The control device 1 can be a computer device capable of collecting power grid data in real time, determining the current power grid operating state according to the power grid data, and determining the demand of the power grid for reactive power or active power. According to the power grid demand, the switching state of the high-low voltage module 21 in the power compensation device 2 is controlled, so that the corresponding high-low voltage module 21 provides reactive power and / or active power to the power grid, so that the power compensation device 2 provides power compensation for the power grid.

[0075] ​The power compensation device 2 can be a cascade type complete device composed of multiple power chain links 22. The power chain links 22 in the power compensation device 2 are composed of multiple high-low voltage modules 21 connected in series in a certain arrangement. The power chain links 22 are connected according to a preset connection mode. Each power chain link 22 is connected to one phase in the power grid and is used to provide power compensation. The preset connection mode can be a star connection, a delta connection, a double star connection, etc. and can be selected according to actual conditions.

[0076] Compared with the traditional mechanical phase modifier, the phase modifier system provided by the present disclosure adopts electrical elements as energy storage units, has no mechanical structure, adopts a static structure, is composed of power electronic devices and control devices, has a reduced size, and has a fast response speed. Meanwhile, the phase modifier system adopts a modular configuration method, can flexibly change the performance of the phase modifier according to the power grid, is convenient for expansion and maintenance, and can adapt to various power grid conditions. Compared with the SVC, the phase modifier system can provide active power support for the power grid.

[0077] In another embodiment provided by the present disclosure, as shown in Figure 2 The high-low voltage module 21 includes a power module 211, a capacitor module 212 and a battery module 213.

[0078] The power module 211 includes multiple power semiconductor devices. The power semiconductor devices include a switch tube and a diode.

[0079] The emitter of the switch tube is connected to the anode of the diode as the output end of the power semiconductor device. The collector of the switch tube is connected to the cathode of the diode as the input end of the power semiconductor device. The gate of the switch tube receives a control instruction and controls the on-off of the switch tube according to the control instruction.

[0080] The power module 211 is connected to the capacitor module 212 and the battery module 213.

[0081] The capacitor module 212 is used to provide reactive power to the power grid.

[0082] The battery module 213 is used to provide active power to the power grid.

[0083] The power module 211 is used to provide reactive power and / or active power to the power grid by controlling the on-off of the capacitor module 212 and the battery module 213 according to the switch state.

[0084] In the embodiment of the present disclosure, the high-low voltage module 21 includes the capacitor module 212, the battery module 213 and the power module 211. The capacitor module 212 can include at least one capacitor as an energy storage element. The capacitor module stores electric field energy and provides capacitive reactive power to the power grid to offset inductive reactive power generated by an inductive load, so as to improve the power factor of the power grid system and improve the voltage stability.

[0085] The battery module 213 can include at least one battery as an energy storage element. The battery module stores chemical energy, which can be converted into electrical energy when the grid has a positive demand for active power, and outputs the electrical energy to the grid, thereby providing active power to the grid to meet the demand of load consumption; when the grid has a negative demand for active power, the active power can be absorbed by charging the battery module 213.

[0086] The battery module in the present disclosure can be a chemical battery, which has a significant cost advantage compared to a super capacitor.

[0087] The power module 211 can include a plurality of power semiconductor devices. By controlling the on-off combination of the power semiconductor devices, the on-off of the capacitor module 212 and the battery module 213 can be controlled, and the corresponding power can be output to the grid.

[0088] The power semiconductor device is composed of a switch tube and a diode. The switch tube can be an insulated gate bipolar transistor (IGBT). The on-off between the collector and the emitter can be controlled by applying a signal to the gate, thereby controlling the on-off of the switch tube. The diode is used to provide a path for reverse current to avoid reverse breakdown of the switch tube, protect the switch tube and maintain normal operation of the circuit.

[0089] Further, the capacitance of the capacitor module 212 can be determined according to the following formula (1).

[0090] (1)

[0091] Wherein is the minimum required capacitance of the capacitor module 212; is the rated voltage of the capacitor module 212; is the reactive capacity of the high-low voltage module 21; is the allowable voltage fluctuation rate, generally not greater than 5%; ω is the grid angular frequency.

[0092] Further, the battery module 213 can be formed by connecting a plurality of battery cells in series. The number of battery cells in the battery module 213 can be determined by first determining the number of high-low voltage modules 21 in the power chain 22, and then determining the number of battery cells in series.

[0093] The number of high-low voltage modules 21 can be determined according to the following formula (2).

[0094] (2)

[0095] Wherein, is the number of high-low voltage modules 21; is the maximum reactive power demand; is the rated current of the AC side of the module; is the rated voltage of the AC side of the module.

[0096] The number of series-connected battery cells of the battery module 213 can be determined according to formula (3) as follows.

[0097] (3)

[0098] wherein, is the number of series-connected battery cells of the battery module 213; is the maximum active power demand; is the charge-discharge time; is the redundancy coefficient; is the capacity of the battery cell; is the rated voltage of the battery cell; is the power conversion efficiency, which can be determined according to the technical parameters of the battery cell; is the depth of discharge of the battery cell.

[0099] The above and can be determined in advance in the design process according to the load type, power, power factor and operating state of the power grid, as well as the dynamic demand of various working conditions.

[0100] Through flexible configuration of the capacitor module and the battery module, the hybrid static phase modifier system provided by the present disclosure realizes comprehensive coverage of various power grid compensation demands, and can make corresponding adjustments to the capacitor module and the battery module according to the development and changes of the power grid, thereby realizing economical use of resources.

[0101] In yet another embodiment of the present disclosure, as shown in Figure 3 , the power module 211 includes a first power semiconductor device 2111, a second power semiconductor device 2112, a third power semiconductor device 2113, a fourth power semiconductor device 2114, a fifth power semiconductor device 2115 and a sixth power semiconductor device 2116;

[0102] The output end of the first power semiconductor device 2111 is connected to the input end of the second power semiconductor device 2112, serving as a first AC port 2117 of the high-low voltage module 21, and the input end of the first power semiconductor device 2111 is connected to one end of the capacitor module 212 and the input end of the third power semiconductor device 2113, respectively;

[0103] The output end of the second power semiconductor device 2112 is connected to the other end of the capacitor module 212 and the output end of the fourth power semiconductor device 2114, respectively;

[0104] The output end of the third power semiconductor device 2113 is connected with the positive pole of the battery module 213 and the input end of the fifth power semiconductor device 2115 respectively;

[0105] The input end of the fourth power semiconductor device 2114 is connected with the negative pole of the battery module 213 and the output end of the sixth power semiconductor device 2116 respectively;

[0106] The output end of the fifth power semiconductor device 2115 is connected with the input end of the sixth power semiconductor device 2116, as the second alternating current port 2118 of the high-low voltage module 21.

[0107] In the embodiment of the present disclosure, the first power semiconductor device 2111 and the second power semiconductor device 2112 form the high-voltage device of the power module 211. In actual application, the elements in the high-voltage device need to withstand higher voltage than the low-voltage device, so as to avoid breakdown damage, and the semiconductor device (including: switch tube and diode) in the first power semiconductor device 2111 and the second power semiconductor device 2112 should have voltage stress level greater than the rated voltage of the capacitor module 212 . Considering the influence of voltage change in the process of capacitor charging and discharging, sufficient safety margin should be designed in actual engineering.

[0108] The third power semiconductor device 2113, the fourth power semiconductor device 2114, the fifth power semiconductor device 2115 and the sixth power semiconductor device 2116 together form the low-voltage device of the power module 211. In actual application, the low-voltage device is connected with other high-low voltage modules 21, and the semiconductor device with relatively low voltage stress level can be selected. Among them, the voltage stress level of the third power semiconductor device 2113 and the fourth power semiconductor device 2114 should be greater than , the rated voltage of the battery module 213, . The voltage stress level of the third power semiconductor device 2113 and the fourth power semiconductor device 2114 should be greater than . Considering the influence of voltage change in the process of battery and capacitor charging and discharging, sufficient safety margin should be designed in actual engineering.

[0109] In another embodiment provided by the present disclosure, the power chain 22 includes a preset number of high-low voltage modules 21 and an output reactor; the preset number is determined according to the reactive power demand of the power grid;

[0110] The first alternating current port 2117 of the high-low voltage module in the power chain 22, except the last-stage high-low voltage module, is connected with the second alternating current port 2118 of another high-low voltage module, and the first alternating current port 2117 of the last-stage high-low voltage module in the power chain 22 is connected with the corresponding phase in the power grid through the output reactor.

[0111] In the power compensation device 2 , any two power links 22 include the same number of high and low voltage modules 21 .

[0112] In the embodiment of the present disclosure, the preset number can be used to first determine the number of high and low voltage modules of the entire power compensation device according to the above formula (2), and then further determine the number of high and low voltage modules of each power link of the power compensation device.

[0113] The power chain link 22 of the power compensation device 2 is composed of multiple high and low voltage modules 21 and output reactors connected in series. Each power chain link 22 is connected to one phase of the power grid and provides power compensation to the grid through the complete set of devices (i.e., power compensation devices). For example, the power chain link 22 in the power compensation device 2 is connected in a star configuration. Figure 4 As shown, the low-voltage device side of the first high- and low-voltage module of each power link 22 is connected via the second AC port 2118, and the low-voltage device side of the secondary high- and low-voltage module in the power link 22 is connected to the high-voltage device side of the first high- and low-voltage module (i.e., the second AC port 2118 of the secondary high- and low-voltage module is connected to the first AC port 2117 of the first high- and low-voltage module). In this way, the high- and low-voltage modules 21 in the power link 22 are combined in series; the first AC port 2117 of the final high- and low-voltage module in the power link 22 is connected to one phase of the power grid via the output inductor 23.

[0114] The reactor can achieve dynamic balance of the power system through its inductive characteristics during the reactive power compensation process.

[0115] In another embodiment provided by the present disclosure, the control device 1 determines the power demand in the power grid based on the power grid data, and separately determines the required voltage of each phase in the power grid;

[0116] When the grid demands reactive power, the control device determines the capacitor voltage of each high- and low-voltage module in the power chain link in each preset cycle, and determines at least one high- and low-voltage module for each power chain link as the first balancing module of the current cycle based on the difference between the capacitor voltage and the preset rated voltage; determines the switching state of the corresponding first balancing module based on the current direction of the grid, and determines the output voltage of the first balancing module;

[0117] When the grid demands active power, the control device determines the battery charge of each high-voltage and low-voltage module in the power chain link in each preset cycle, and determines at least one high-voltage and low-voltage module for each power chain link as the second balancing module for this cycle based on the difference between the battery charge and the preset battery charge. The control device also determines the switching state of the corresponding second balancing module based on the current direction of the grid and determines the output voltage of the second balancing module.

[0118] In the embodiments of the present disclosure, the control device 1 can collect power grid data, wherein the power grid data can include: power grid voltage, power grid current and power grid frequency. The control device 1 can calculate the power grid demand power by using the grid control algorithm, and then solve the demand voltage of each phase The demand voltage is the voltage level that the power grid needs to maintain during the operation of the power grid in order to maintain the stability of the entire system and the power supply quality. In the present disclosure, the demand voltage is taken as one of the reference bases for power compensation.

[0119] When the power grid requires reactive power, the control device 1 detects the capacitance voltage of the capacitance module 212 of all high-low voltage modules 21 in each power chain 22 in each preset period, compares the capacitance voltage with the preset rated voltage, and determines the absolute value of the difference between the two for each high-low voltage module 21 in each power chain, and determines the high-low voltage module 21 with the maximum absolute value as the first balancing module in this preset period.

[0120] The preset rated voltage is a value determined in advance according to the capacitance rated voltage. When the capacitance voltage is greater than this value, it can be considered that the module voltage is too high, and the switch state that can discharge the capacitance needs to be selected; when the capacitance voltage is less than this value, it can be considered that the module voltage is too low, and the switch state that can charge the capacitance needs to be selected. Because the direction of the power grid current is different under the same switch state, it will cause the charging and discharging state of the capacitance module to be different, so the control device needs to switch the switch state of the first balancing module according to the direction of the current. That is, when the power grid requires reactive power, the switch state of the first balancing module can be determined as the switch state in which the battery module is disconnected and the capacitance module can be charged and discharged (i.e., the first switch state and the fourth switch state).

[0121] The first balancing module can be the high-low voltage module with the maximum deviation from the rated voltage in each power chain that provides reactive power for the power grid. The control module can sample the output voltage of the high-low voltage module, and determine the corresponding reference voltage for other high-low voltage modules in the power chain according to the output voltage; and further according to the reference voltage, formulate the corresponding modulation strategy for the high-low voltage modules in the power chain (i.e., adjust the switch state of the high-low voltage module).

[0122] When the grid requires active power, the control device 1 detects the power of the battery module 213 of all high-low voltage modules 21 in each preset period, compares the power of the battery module 213 with the preset battery power, and selects the switch state of the battery module 213. When the power of the battery module is greater than the preset value, it is considered that the module can provide active power to the grid, and the switch state of the battery module is selected to discharge; when the power of the battery module is less than the preset value, it is considered that the module can absorb active power from the grid, and the switch state of the battery module is selected to charge.

[0123] When the grid requires positive active power, determine the high-low voltage module with the maximum power in each power chain, and determine this high-low voltage module as the second balancing module in this preset period, and select the switch state of the battery to discharge according to the grid current.

[0124] When the grid requires negative active power, determine the high-low voltage module with the minimum power in each power chain. Determine this high-low voltage module as the second balancing module in this preset period, and select the switch state of the battery to discharge according to the grid current.

[0125] The second balancing module can be the high-low voltage module with the maximum deviation from the preset battery power in each power chain that provides active power to the grid. The control module can sample the output voltage of the high-low voltage module, and determine the corresponding reference voltage for other high-low voltage modules in the power chain according to the output voltage; and further according to the reference voltage, formulate the corresponding modulation strategy (i.e. adjust the switch state of the high-low voltage module) for the high-low voltage module in the power chain.

[0126] The preset period can be an integer multiple of the fundamental period, and the fundamental period represents the shortest time interval required for the signal to repeat itself. The preset battery power can be the average value of the power of the battery module 213 of all high-low voltage modules 21 in the power chain 22.

[0127] In each preset period, according to the grid power requirement, a new high-low voltage module 21 is selected as the first or second balancing module for balancing the state deviation of the battery and the capacitor caused by the inconsistency of the components during system operation.

[0128] It should be noted that the number of balancing modules selected in each cycle in the above implementation process can be adjusted according to the actual grid requirement, for example, two high-low voltage modules are determined in each power chain as the first or second balancing module of the current period, and the specific implementation and the idea of the embodiment are completely the same.

[0129] The above steps can be executed as shown in the flowchart of Figure 5 .

[0130] In yet another embodiment of the present disclosure, in the case where the high-low voltage module in the power chain segment is determined as the first equalization module, the control device determines a first reference voltage of the power chain segment according to the demand voltage, the output voltage of the first equalization module, and the number of high-low voltage modules in the power chain segment, and determines the switching state of the high-low voltage module in the power chain segment other than the first equalization module according to the first reference voltage.

[0131] In the case where the first reference voltage is greater than a first threshold value, the high-low voltage module is determined as the first switching state.

[0132] In the case where the first reference voltage is less than the first threshold value and greater than a second threshold value, the high-low voltage module is determined as the second switching state or the third switching state.

[0133] In the case where the first reference voltage is less than the second threshold value, the high-low voltage module is determined as the fourth switching state.

[0134] In the embodiment of the present disclosure, the control device 1 determines the output voltage of the high-low voltage module 21 selected as the first equalization module or the second equalization module, and obtains the reference voltage of the power chain segment corresponding to the phase according to the demand voltage of the corresponding phase in the power grid and the number of high-low voltage modules 21 in the power chain segment 22 corresponding to the phase. The reference voltage can be determined according to the following formula (4).

[0135] (4)

[0136] Wherein, is the reference voltage; is the demand voltage of the corresponding phase, is the output voltage of the corresponding high-low voltage module (i.e. the first equalization module or the second equalization module).

[0137] The first reference voltage can be the modulation voltage of each high-low voltage module 21 in the power chain segment 22 in the process of providing reactive power for the power grid, and the control device 1 can send a control instruction to change the switching state of each high-low voltage module in the power chain segment other than the first equalization module according to the modulation voltage.

[0138] The first threshold value can be the voltage value at the connection between the power module 211 and the capacitor module 212 in the high-low voltage module 21 , and the second threshold value can be .

[0139] That is, for each high-low voltage module, when , the control device 1 controls the corresponding high-low voltage module to be in the first switching state; when , the control device 1 controls the corresponding high-low voltage module to be in the second or third switching state; and when In the case that the high-low voltage module is determined as the second equalization module in the power chain link, the control device determines a second reference voltage of the power chain link according to the demand voltage, the output voltage of the second equalization module, and the number of high-low voltage modules in the power chain link, and determines the switching state of the high-low voltage module other than the second equalization module in the power chain link according to the second reference voltage. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0140] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. Figure 6 The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0141] In the case that the high-low voltage module is determined as the second equalization module in the power chain link, the control device determines a second reference voltage of the power chain link according to the demand voltage, the output voltage of the second equalization module, and the number of high-low voltage modules in the power chain link, and determines the switching state of the high-low voltage module other than the second equalization module in the power chain link according to the second reference voltage. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0142] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0143] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0144] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0145] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0146] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0147] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0148] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid.

[0149] The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. The first reference voltage is a voltage provided by the power chain link to the power grid, and the second reference voltage is a voltage provided by the power chain link to the power grid. In the case where the high-low voltage module 21 is in the first switching state, the control device 1 controls the corresponding high-low voltage module to be in the fifth or sixth switching state; when In the case where the high-low voltage module 21 is in the second switching state, the control device 1 controls the corresponding high-low voltage module to be in the second or third switching state; when In the case where the high-low voltage module 21 is in the seventh switching state, the control device 1 controls the corresponding high-low voltage module to be in the seventh or eighth switching state; when In the case where the high-low voltage module 21 is in the third switching state, the control device 1 controls the corresponding high-low voltage module to be in the third switching state. Wherein, The second reference voltage is the voltage of the capacitor module 212.

[0150] Taking the voltage output at the connection between the power module and the capacitor module as a triangular wave for example, the carrier modulation strategy of the phase-modulator system during active power support is as shown in FIG. 8. Figure 7

[0151] In another embodiment of the present disclosure, in the case where the high-low voltage module 21 is in the first switching state, the first power semiconductor device 2111, the fourth power semiconductor device 2114 and the sixth power semiconductor device 2116 are turned on, the second power semiconductor device 2112, the third power semiconductor device 2113 and the fifth power semiconductor device 2115 are turned off, the battery module 213 is disconnected, and the capacitor module 212 is turned on.

[0152] In the case where the high-low voltage module 21 is in the second switching state, the first power semiconductor device 2111, the third power semiconductor device 2113 and the fifth power semiconductor device 2115 are turned on, the second power semiconductor device 2112, the fourth power semiconductor device 2114 and the sixth power semiconductor device 2116 are turned off, the battery module 213 and the capacitor module 212 are disconnected.

[0153] In the case where the high-low voltage module 21 is in the third switching state, the first power semiconductor device 2111, the third power semiconductor device 2113 and the fifth power semiconductor device 2115 are turned off, the second power semiconductor device 2112, the fourth power semiconductor device 2114 and the sixth power semiconductor device 2116 are turned on, the battery module 213 and the capacitor module 212 are disconnected.

[0154] In the case where the high-low voltage module 21 is in the fourth switching state, the first power semiconductor device 2111, the fourth power semiconductor device 2114 and the sixth power semiconductor device 2116 are turned off, the second power semiconductor device 2112, the third power semiconductor device 2113 and the fifth power semiconductor device 2115 are turned on, the battery module 213 is disconnected, and the capacitor module 212 is turned on.

[0155] ​In the embodiments of the present disclosure, the switching states of the first power semiconductor device 2111 and the second power semiconductor device 2112, the third power semiconductor device 2113 and the fourth power semiconductor device 2114, and the fifth power semiconductor device 2115 and the sixth power semiconductor device 2116 of the high-low voltage module 21 are complementary.

[0156] When the battery module 213 is in the off state, the high-low voltage module 21 cannot provide active power to the power grid. When the capacitor module 212 is in the on state, the capacitor module 212 can provide reactive power to the power grid, and the capacitor module 212 is charged and discharged according to the current direction. When the battery module 213 and the capacitor module 212 are both in the off state, the high-low voltage module 21 has no effect on the power grid.

[0157] In another embodiment of the present disclosure, when the high-low voltage module 21 is in the fifth switching state, the first power semiconductor device 2111, the fourth power semiconductor device 2114, and the fifth power semiconductor device 2115 are turned on, the second power semiconductor device 2112, the third power semiconductor device 2113, and the sixth power semiconductor device 2116 are turned off, and the battery module 213 and the capacitor module 212 are turned on.

[0158] When the high-low voltage module 21 is in the sixth switching state, the first power semiconductor device 2111, the third power semiconductor device 2113, and the sixth power semiconductor device 2116 are turned on, the second power semiconductor device 2112, the fourth power semiconductor device 2114, and the fifth power semiconductor device 2115 are turned off, the battery module 213 is turned on, and the capacitor module 212 is turned off.

[0159] When the high-low voltage module 21 is in the seventh switching state, the first power semiconductor device 2111, the third power semiconductor device 2113, and the sixth power semiconductor device 2116 are turned off, the second power semiconductor device 2112, the fourth power semiconductor device 2114, and the fifth power semiconductor device 2115 are turned on, the battery module 213 is turned on, and the capacitor module 212 is turned off.

[0160] When the high-low voltage module 21 is in the eighth switching state, the first power semiconductor device 2111, the fourth power semiconductor device 2114, and the fifth power semiconductor device 2115 are turned off, the second power semiconductor device 2112, the fourth power semiconductor device 2114, and the sixth power semiconductor device 2116 are turned on, and the battery module 213 and the capacitor module 212 are turned on.

[0161] In the embodiment of the present disclosure, when the battery module 213 is in the on state, the high-low voltage module 21 can provide active power to the power grid, and charge or discharge the battery module according to the positive or negative active power demand of the power grid. When the battery module 213 and the capacitor module 212 are both in the on state, the high-low voltage module 21 can provide active power and reactive power to the power grid.

[0162] Here, one high-low voltage module switch state table shown in Table 1 is provided as an example.

[0163]

[0164] Table 1: High-low voltage module switch state table

[0165] In the above table, 1 represents that the power semiconductor device is in the on state, and 0 represents that the power semiconductor device is in the off state; is the rated voltage of the capacitor module 212, is the rated voltage of the battery module 213.

[0166] According to the above table, the high-low voltage module 21 provided by the embodiment of the present disclosure can provide eight switch states in total and output seven level states; if then the input level state is five. In each level state, the battery module 213 and the capacitor module 212 have different charging and discharging relationships according to the current direction.

[0167] In another embodiment of the present disclosure, when the power grid requires active power, the control device determines the switch state of the high-low voltage module according to the current direction of the power grid and the required voltage of the power grid;

[0168] When the power grid requires positive active power and the current direction is the first direction, the high-low voltage module is determined to be one of the first switch state, the second switch state, the third switch state, the fourth switch state, the fifth switch state or the seventh switch state according to the output voltage and the required voltage of the corresponding power chain;

[0169] When the power grid requires positive active power and the current direction is the second direction, the high-low voltage module is determined to be one of the first switch state, the second switch state, the third switch state, the fourth switch state, the sixth switch state or the eighth switch state according to the output voltage and the required voltage of the corresponding power chain;

[0170] When the power grid requires negative active power and the current direction is the second direction, the high-low voltage module is determined to be one of the first switch state, the second switch state, the third switch state, the fourth switch state, the fifth switch state or the seventh switch state according to the output voltage and the required voltage of the corresponding power chain;

[0171] When the active power required by the power grid is negative and the current direction is the first direction, the high and low voltage modules are determined to be in one of the first switching state, the second switching state, the third switching state, the fourth switching state, the sixth switching state or the eighth switching state according to the output voltage and the required voltage of the corresponding power chain link.

[0172] In the embodiment of the present disclosure, the current can be the current of each phase line of the power grid , the first direction can refer to , the second direction can refer to .

[0173] Since the direction of current in the AC power grid changes periodically, if the high and low voltage modules 21 are in the same switching state, the change in current direction may cause the battery module 213 to frequently change its charge and discharge state, thereby reducing the battery life.

[0174] The control device 1 provided in the embodiment of the present disclosure can also change the switching state of the high and low voltage modules 21 according to the direction of the current, so that the battery module 213 remains in the charging or discharging state.

[0175] The charge and discharge requirements of the battery module 213 can be determined based on the total voltage output by the power link 22 and the required voltage of the corresponding phase. The total voltage output by the power chain link 22 can be determined according to the following formula (5):

[0176] (5)

[0177] in, is the total voltage output by the power link 22; for The corresponding power link 22 The output voltage of the high and low voltage module 21; The output voltage is The number of submodules of the case; Indicates the switch status of the high and low voltage module 21.

[0178] The control device can adjust the switch state of each high and low voltage module according to the total output voltage of the power chain link, so that , so that the phase regulator can meet the current power demand of the power grid.

[0179] When the battery module 213 requires active discharge, the control device 1 will change the switch state of the corresponding high and low voltage modules 21 according to the current direction. When , the switch state is determined to be the fifth switch state or the seventh switch state; when , it is determined that the switch state is the sixth switch state or the eighth switch state.

[0180] In the case that the battery module 213 needs active charging, the control device 1 will change the switch state of the corresponding high-low voltage module 21 according to the current direction. When the current direction is the first direction, the switch state is determined as the fifth switch state or the seventh switch state; when the current direction is the second direction, the switch state is determined as the sixth switch state or the eighth switch state.

[0181] In this way, the repeated switching of the battery module 213 in different control periods can be avoided, and the simultaneous existence of discharging and charging can be avoided, thereby improving the service life of the battery module.

[0182] In another embodiment provided by the present disclosure, in the case that the current direction is the first direction and the capacitor voltage of the first equalization module is greater than the preset rated voltage, the switch state of the first equalization module is determined as the fourth switch state.

[0183] In the case that the current direction is the second direction and the capacitor voltage of the first equalization module is greater than the preset rated voltage, the switch state of the first equalization module is determined as the first switch state.

[0184] In the case that the current direction is the first direction and the capacitor voltage of the first equalization module is less than the preset rated voltage, the switch state of the first equalization module is determined as the first switch state.

[0185] In the case that the current direction is the second direction and the capacitor voltage of the first equalization module is less than the preset rated voltage, the switch state of the first equalization module is determined as the fourth switch state.

[0186] In the embodiment of the present disclosure, the first equalization module is a high-low voltage module with the largest deviation between the capacitor voltage and the rated voltage in a power chain. When the capacitor voltage of the first equalization module is greater than the rated voltage, it indicates that the charge stored in the capacitor module of the high-low voltage module is relatively large, and it needs to be continuously discharged to reduce the charge stored therein, so as to reduce the output voltage and maintain the stability of the power chain. In this case, the switch state of the first equalization module can be determined according to the current direction to be in a state that enables the capacitor to be discharged.

[0187] When the capacitor voltage of the first equalization module is less than the rated voltage, it indicates that the charge stored in the capacitor module of the high-low voltage module is relatively small, and it needs to be continuously charged to increase the charge stored therein, so as to increase the output voltage. In this case, the switch state of the first equalization module can be determined according to the current direction to be in a state that enables the capacitor to be charged.

[0188] In another embodiment provided by the present disclosure, in the case that the current direction is the first direction and the battery capacity of the second equalization module is greater than the preset capacity, the switch state of the second equalization module is determined as one of the fifth switch state or the seventh switch state.​​

[0189] In a case where the current direction is the first direction and the battery power of the second equalization module is less than the preset power, the switch state of the second equalization module is determined as one of the sixth switch state or the eighth switch state.

[0190] In a case where the current direction is the second direction and the battery power of the second equalization module is less than the preset power, the switch state of the second equalization module is determined as one of the fifth switch state or the seventh switch state.

[0191] In a case where the current direction is the second direction and the battery power of the second equalization module is greater than the preset power, the switch state of the second equalization module is determined as one of the sixth switch state or the eighth switch state.

[0192] In the embodiments of the present disclosure, the second equalization module is a high-low voltage module with the largest deviation of the battery power from the rated power in a power chain link. When the battery power is greater than the rated power, it indicates that the stored power in the battery module is higher than the stored power in other high-low voltage modules in the power chain link. The second equalization module needs to be continuously discharged to make the stored power return to a level close to that of other high-low voltage modules in the power chain link, so as to stabilize the active power output by the power chain link. In this case, the switch state of the second equalization module can be determined according to the current direction to be in a switch state that enables the battery module to be discharged.

[0193] When the battery power is less than the rated power, it indicates that the stored power in the battery module is lower than the stored power in other high-low voltage modules in the power chain link. The second equalization module needs to be continuously charged to make the stored power increase to a level close to that of other high-low voltage modules in the power chain link, so as to stabilize the active power absorbed by the power chain link. In this case, the switch state of the second equalization module can be determined according to the current direction to be in a switch state that enables the battery module to be charged.

[0194] The present disclosure also provides an electronic device comprising the hybrid static phase modifier system provided in any of the above embodiments.

[0195] From the above description of the embodiments, those skilled in the art can clearly understand that the embodiments of the present disclosure can be implemented by hardware, or by means of software and necessary general hardware platforms. Based on such understanding, the technical solutions of the embodiments of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a U disk, a mobile hard disk, etc.), and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present disclosure.

[0196] Those skilled in the art can understand that the modules or flows in the drawings are not necessarily required for implementing the present disclosure.

[0197] Those skilled in the art can understand that the modules in the devices in the embodiments can be distributed in the devices in the embodiments according to the embodiment description, or can be changed to be located in one or more devices different from the embodiments. The modules in the above embodiments can be combined into one module, or can be further split into multiple sub-modules.

[0198] The serial numbers of the embodiments of the present disclosure are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0199] Obviously, those skilled in the art can make various modifications and variations to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure belong to the scope of the claims of the present disclosure and the equivalent technologies thereof, the present disclosure also intends to include these modifications and variations.

Claims

1. A hybrid static phase condenser system, characterized in that: include: Control devices and power compensation devices; The power compensation device includes a plurality of high and low voltage modules; The high and low voltage modules are connected in series to form power links of the power compensation device; the power links are connected in a preset manner and are respectively connected to corresponding phases in the power grid to provide power compensation for the power grid; The control device is used to collect grid data, determine grid demand based on the grid data, and send control instructions to control the high and low voltage modules in the power compensation device to change the switch state; The high and low voltage modules are used to provide reactive power and / or active power to the power grid through the power compensation device according to the switch state; The high and low voltage modules include: a power module, a capacitor module and a battery module; The power module is connected to the capacitor module and the battery module respectively; the power module is used to provide reactive power and / or active power to the power grid by controlling the on / off of the capacitor module and the battery module according to the switch state; The capacitor module is used to provide reactive power to the power grid; The battery module is used to provide active power to the power grid; The control device is also used to change the switching state of the high and low voltage modules according to the direction of the current, so that the battery module remains in the charging or discharging state.

2. The system according to claim 1, wherein The power module includes a plurality of power semiconductor devices; the power semiconductor devices include: a switch tube and a diode; The emitter of the switching tube is connected to the positive electrode of the diode as the output end of the power semiconductor device, the collector of the switching tube is connected to the negative electrode of the diode as the input end of the power semiconductor device, and the gate of the switching tube receives the control instruction and controls the on and off of the switching tube according to the control instruction.

3. The system according to claim 2, wherein: The power module includes a first power semiconductor device, a second power semiconductor device, a third power semiconductor device, a fourth power semiconductor device, a fifth power semiconductor device and a sixth power semiconductor device; The output end of the first power semiconductor device is connected to the input end of the second power semiconductor device, serving as the first AC port of the high and low voltage modules, and the input end of the first power semiconductor device is connected to one end of the capacitor module and the input end of the third power semiconductor device respectively; The output end of the second power semiconductor device is connected to the other end of the capacitor module and the output end of the fourth power semiconductor device respectively; The output end of the third power semiconductor device is connected to the positive electrode of the battery module and the input end of the fifth power semiconductor device respectively; The input end of the fourth power semiconductor device is respectively connected to the negative electrode of the battery module and the output end of the sixth power semiconductor device; The output end of the fifth power semiconductor device is connected to the input end of the sixth power semiconductor device, serving as the second AC port of the high and low voltage module.

4. The system according to claim 1, wherein: The power chain includes a preset number of high and low voltage modules and output reactors; the preset number is determined according to the reactive power demand of the power grid; The first AC port of the high and low voltage modules other than the final high and low voltage module in the power chain is connected to the second AC port of another high and low voltage module, and the first AC port of the final high and low voltage module in the power chain is connected to the corresponding phase in the power grid through the output reactor; In the power compensation device, any two power links include the same number of high and low voltage modules.

5. The system according to claim 3, wherein: The control device determines the power demand of the power grid according to the power grid data, and determines the required voltage of each phase in the power grid respectively; When the grid requires reactive power, the control device determines the capacitor voltage of each high-voltage and low-voltage module in the power chain in each preset cycle, and determines at least one high-voltage and low-voltage module for each power chain as the first balancing module in this cycle based on the difference between the capacitor voltage and the preset rated voltage; Determining a switch state of a corresponding first balancing module according to a current direction of the power grid, and determining an output voltage of the first balancing module; When the power grid requires active power, the control device determines the battery power of each high-voltage and low-voltage module in the power chain link in each preset cycle, and determines at least one high-voltage and low-voltage module for each power chain link as the second balancing module of the current cycle based on the difference between the battery power and the preset battery power; determines the switching state of the corresponding second balancing module based on the current direction of the power grid, and determines the output voltage of the second balancing module.

6. The system according to claim 5, wherein: In a case where a high- and low-voltage module in a power link is determined as a first balancing module, the control device determines a first reference voltage of the power link according to the required voltage, the output voltage of the first balancing module, and the number of high- and low-voltage modules in the power link; and determines the switching states of the high- and low-voltage modules in the power link other than the first balancing module according to the first reference voltage; When the first reference voltage is greater than a first threshold, determining that the high and low voltage modules are in a first switch state; When the first reference voltage is less than a first threshold and greater than a second threshold, determining that the high and low voltage modules are in the second switching state or the third switching state; When the first reference voltage is less than the second threshold, the high and low voltage modules are determined to be in the fourth switch state.

7. The system according to claim 5, wherein: When a high- and low-voltage module is determined as a second balancing module in a power chain, the control device determines a second reference voltage of the power chain according to the required voltage, the output voltage of the second balancing module, and the number of high- and low-voltage modules in the power chain; and determines the switching states of the high- and low-voltage modules in the power chain other than the second balancing module according to the second reference voltage; When the second reference voltage is greater than the first threshold, determining that the high and low voltage modules are in the first switch state; When the second reference voltage is less than the first threshold and greater than the third threshold, determining that the high and low voltage modules are in the fifth switching state or the sixth switching state; When the second reference voltage is less than the third threshold and greater than the fourth threshold, determining that the high and low voltage modules are in the second switching state or the third switching state; When the second reference voltage is less than the fourth threshold and greater than the second threshold, determining that the high and low voltage modules are in the seventh switching state or the eighth switching state; When the second reference voltage is less than a second threshold, the high and low voltage module is determined to be in a fourth switch state.

8. The system according to claim 6, wherein: When the high and low voltage modules are in the first switching state, the first power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned on, the second power semiconductor device, the third power semiconductor device and the fifth power semiconductor device are turned off, the battery module is disconnected, and the capacitor module is turned on; When the high and low voltage modules are in the second switching state, the first power semiconductor device, the third power semiconductor device and the fifth power semiconductor device are turned on, the second power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned off, and the battery module and the capacitor module are disconnected; When the high and low voltage modules are in the third switching state, the first power semiconductor device, the third power semiconductor device and the fifth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned on, and the battery module and the capacitor module are disconnected; When the high and low voltage module is in the fourth switching state, the first power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned off, the second power semiconductor device, the third power semiconductor device and the fifth power semiconductor device are turned on, the battery module is disconnected, and the capacitor module is turned on.

9. The system according to claim 7, wherein: When the high and low voltage module is in the fifth switching state, the first power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned on, the second power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned off, and the battery module and the capacitor module are turned on; When the high and low voltage module is in the sixth switching state, the first power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned on, the second power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned off, the battery module is turned on, and the capacitor module is disconnected; When the high and low voltage module is in the seventh switching state, the first power semiconductor device, the third power semiconductor device and the sixth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned on, the battery module is turned on, and the capacitor module is disconnected; When the high and low voltage module is in the eighth switching state, the first power semiconductor device, the fourth power semiconductor device and the fifth power semiconductor device are turned off, the second power semiconductor device, the fourth power semiconductor device and the sixth power semiconductor device are turned on, and the battery module and the capacitor module are turned on.

10. The system according to claim 7, wherein: When the grid requires active power, the control device determines the switch state of the high and low voltage modules according to the current direction of the grid and the required voltage of the grid; When the grid active power requirement is positive and the current direction is the first direction, determining that the high and low voltage modules are in one of the first switching state, the second switching state, the third switching state, the fourth switching state, the fifth switching state, or the seventh switching state according to the output voltage of the corresponding power link and the required voltage; When the grid active power requirement is positive and the current direction is the second direction, determining that the high and low voltage modules are in one of the first switching state, the second switching state, the third switching state, the fourth switching state, the sixth switching state, or the eighth switching state according to the output voltage of the corresponding power link and the required voltage; When the grid required active power is negative and the current direction is the second direction, determining, according to the output voltage of the corresponding power link and the required voltage, whether the high and low voltage modules are in the first switching state, the second switching state, the third switching state, the fourth switching state, the fifth switching state, or the seventh switching state; When the active power required by the power grid is negative and the current direction is the first direction, the high and low voltage modules are determined to be in one of the first switching state, the second switching state, the third switching state, the fourth switching state, the sixth switching state or the eighth switching state according to the output voltage of the corresponding power chain link and the required voltage.

11. The system according to claim 5, wherein: When the current direction is the first direction and the capacitor voltage of the first balancing module is greater than a preset rated voltage, determining that the switch state of the first balancing module is a fourth switch state; When the current direction is the second direction and the capacitor voltage of the first balancing module is greater than a preset rated voltage, determining that the switch state of the first balancing module is the first switch state; When the current direction is the first direction and the capacitor voltage of the first balancing module is less than a preset rated voltage, determining that the switch state of the first balancing module is the first switch state; When the current direction is the second direction and the capacitor voltage of the first balancing module is less than a preset rated voltage, the switch state of the first balancing module is determined to be the fourth switch state.

12. The system according to claim 5, wherein: When the current direction is the first direction and the battery power of the second balancing module is greater than a preset power, determining that the switching state of the second balancing module is one of the fifth switching state or the seventh switching state; When the current direction is the first direction and the battery power of the second balancing module is less than a preset power, determining that the switching state of the second balancing module is one of the sixth switching state or the eighth switching state; When the current direction is the second direction and the battery power of the second balancing module is less than a preset power, determining that the switching state of the second balancing module is one of the fifth switching state or the seventh switching state; When the current direction is the second direction and the battery power of the second balancing module is greater than a preset power, the switching state of the second balancing module is determined to be one of the sixth switching state and the eighth switching state.

13. An electronic device, characterized in that: include: The hybrid static phase condenser system according to claims 1-12.

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