A voltage regulating module, a voltage regulating control method, a flexible voltage regulating device and a power system

Abstract

The present application relates to a kind of voltage regulating module, voltage regulating control method, flexible voltage regulating device and power system, the voltage regulating module is by multiple thyristor bridge arms with auxiliary switching circuit parallel, the middle connecting point of each bridge arm is the input of voltage regulating module, one end after multiple thyristor bridge arms parallel as first output terminal, the other end as second output terminal, multiple thyristor bridge arms are based on the control signal received by flexible voltage regulating control method, turn on or turn off, realize the step regulation of output voltage, can effectively solve the problem that traditional on-load regulating switch is caused by the mechanical transmission part, leading to long voltage regulating response time, not across the voltage regulating, the number of switch actions is limited, perfect instead on-load regulating switch for voltage regulating, it is favorable to improve the voltage regulating performance of on-load regulating transformer, prolong the service life of on-load regulating transformer.

Description

Technical Field

[0001] This invention relates to the field of power system technology, specifically to a voltage regulating module, a voltage regulating control method, a flexible voltage regulating device, and a power system. Background Technology

[0002] As power systems grow larger and more complex, their operational complexity also increases, posing numerous challenges to stable voltage operation. To meet the requirements of power system voltage stability, on-load tap changer (OLTC) voltage regulation is currently the most mature and commonly used technology. Although OLTC has the advantage of adjusting its winding taps to regulate voltage without interrupting power supply, it requires complex mechanical and electrical components during switching. During on-load voltage regulation, each closing and opening of the mechanical contacts of the on-load tap changer generates a large electric arc, which may damage the contacts, thus affecting the voltage regulation performance of the transformer and shortening its service life. At the same time, the on-load tap changer has a mechanical transmission part, resulting in a long voltage regulation response time, slow action speed, inability to cross-taper voltage regulation, and inability to perform dynamic on-load voltage regulation. The number of switch actions is limited, and the mechanical transmission part is prone to failure. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention proposes a voltage regulating module, a voltage regulating control method, a series-parallel flexible voltage regulating device, and a power system.

[0004] In a first aspect, the present invention provides a voltage regulating module suitable for a series-parallel type flexible voltage regulating device, the voltage regulating module comprising multiple thyristor bridge arms with auxiliary switching circuits, multiple input terminals, a first output terminal, and a second output terminal; One end of the multiple thyristor bridge arms connected in parallel serves as the first output terminal, and the other end serves as the second output terminal; One end of each input terminal is connected to the middle connection point of a thyristor bridge arm; The other end of each input terminal is connected to the tap corresponding to each input terminal in an external multi-winding multi-tap transformer. The plurality of thyristor bridge arms are used to turn on or off based on the received control signals to achieve graded adjustment of the output voltage of the voltage regulation module.

[0005] Optionally, each of the thyristor bridge arms includes an upper bridge arm and a lower bridge arm, one end of the upper bridge arm is connected to one end of the lower bridge arm, the other ends of all the upper bridge arms are connected to form a first output terminal, and the other ends of all the lower bridge arms are connected to form a second output terminal.

[0006] Optionally, both the upper bridge arm and the lower bridge arm include a main circuit and an auxiliary switching circuit connected in parallel; the main circuit includes forward and reverse thyristors; the auxiliary switching circuit includes a current-limiting resistor and forward and reverse thyristors connected in series. The upper bridge arm and the lower bridge arm are used to turn on or off the forward and reverse thyristors based on the received control signal, switch the range of the voltage regulation module, and realize the graded adjustment of the output voltage of the voltage regulation module.

[0007] Optionally, during normal operation without shifting gears, at the same time, only one of the main circuits of the upper bridge arm has its forward and reverse thyristors conducting, and only one of the main circuits of the lower bridge arm has its forward and reverse thyristors conducting, while the thyristors of the auxiliary switching circuits of all bridge arms are not conducting.

[0008] Optionally, during gear shifting, the main circuit of the outgoing axle arm, the main circuit of the incoming axle arm, and the auxiliary shifting circuit work together to achieve smooth gear shifting.

[0009] Optionally, each of the thyristor bridge arms adopts a modular design, and the modular structure of each thyristor bridge arm is divided into upper and lower layers. The lower layer consists of forward and reverse thyristors for the main circuit, and the upper layer consists of current-limiting resistors and forward and reverse thyristors for the auxiliary switching circuit.

[0010] Optionally, the forward and reverse thyristors are press-fit thyristors, with a heat sink between two adjacent press-fit thyristors, and the teeth of the heat sink are vertical.

[0011] Optionally, the forward and reverse thyristors in the auxiliary switching circuit are thyristors whose rated on-current is less than the rated current of the auxiliary switching circuit.

[0012] Optionally, the voltage regulating module further includes a silent fan for dissipating heat from the thyristor.

[0013] Optionally, the voltage regulating module further includes: a first output copper busbar, a second output copper busbar, and multiple input copper busbars; The first output copper busbar is connected to the first output terminal, the second output copper busbar is connected to the second output terminal, and each input copper busbar is connected to one input terminal. The first output copper bus and the second output copper bus are used to lead out the first output terminal and the second output terminal; Each of the input copper busbars is used to bring out each of the input terminals.

[0014] A second aspect of the present invention also provides a voltage regulation control method applicable to the voltage regulation module described in the first aspect of the present invention, the method comprising: Based on the output voltage requirements of the voltage regulation module, the switching range of the voltage regulation module is obtained; Based on the switching gear and the current gear of the voltage regulation module, the bridge arm corresponding to the current gear and the bridge arm corresponding to the switching gear are controlled to realize the graded adjustment of the output voltage of the voltage regulation module.

[0015] Optionally, controlling the bridge arm corresponding to the current gear and the bridge arm corresponding to the switching gear based on the switching gear of the voltage regulating module includes: Based on the switching gear and the current gear of the voltage regulation module, the main circuit of the bridge arm corresponding to the current gear is disconnected, and the auxiliary switching circuit of the bridge arm corresponding to the switching gear is turned on. Based on the current in the main circuit of the bridge arm corresponding to the current gear, control the auxiliary switching circuit of the bridge arm corresponding to the switching gear to be disconnected. Based on the current in the auxiliary switching circuit of the bridge arm corresponding to the switching gear, the main circuit of the bridge arm corresponding to the switching gear is controlled to be turned on.

[0016] Optionally, controlling the auxiliary switching circuit of the bridge arm corresponding to the switching gear to disconnect based on the current in the main circuit of the bridge arm corresponding to the current gear includes: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the trigger pulses of the forward and reverse thyristors in the auxiliary switching circuit of the bridge arm corresponding to the switching gear are canceled.

[0017] Optionally, controlling the main circuit of the bridge arm corresponding to the switching gear to be turned on based on the current in the auxiliary switching circuit of the bridge arm corresponding to the switching gear includes: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the forward and reverse thyristors in the main circuit of the bridge arm corresponding to the gear being switched are activated.

[0018] Optionally, before determining the switching position of the voltage regulator module based on its output voltage requirement, the method further includes: Based on the start command of the voltage regulating module, the initial gear of the voltage regulating module is obtained; Based on the initial gear position of the voltage regulating module, the main circuit of the upper axle arm corresponding to the initial gear position is turned on, and the main circuit of the lower axle arm corresponding to the initial gear position is turned on.

[0019] A third aspect of the present invention also provides a series-parallel type flexible voltage regulating device, the voltage regulating device comprising: an input terminal, a multi-winding multi-tap transformer, multiple voltage regulating modules, multiple series transformers, and multiple output terminals; The input terminal is connected to the three-phase high-voltage winding of the multi-winding multi-tap transformer and the three-phase high-voltage winding of each of the series transformers. The three-phase high-voltage winding of each of the series transformers is also connected to one of the output terminals; Each of the voltage regulating modules is connected to a low-voltage winding of one phase of the multi-winding multi-tap transformer and a low-voltage winding of one phase of the series transformer. Each input terminal is connected to an external power source, and each output terminal is connected to an external load. The plurality of voltage regulating modules are the voltage regulating modules described in the first aspect of the present invention.

[0020] Optionally, the multi-winding multi-tap transformer includes: a plurality of low-voltage windings; each of the low-voltage windings includes a plurality of taps; One end of the three-phase high-voltage winding is connected to the input terminal, and the other end of the three-phase high-voltage winding is connected to form the neutral point on the high-voltage side of the transformer. Each tap of each of the low-voltage windings is connected to an input terminal of one of the voltage regulating modules.

[0021] Optionally, the first output terminal of each voltage regulating module is connected to one end of one phase low-voltage winding of one of the series transformers, and the other ends of the three phase low-voltage windings of each series transformer are connected to the second output terminal of each voltage regulating module and grounded. One end of the high-voltage winding in each of the series transformers is connected to the input terminal, and the other end of the high-voltage winding in each of the series transformers is connected to one of the output terminals.

[0022] Optionally, the number of voltage regulating modules in the series-parallel flexible voltage regulating device is three times the number of series transformers.

[0023] Optionally, the voltage regulating device further includes: a controller; The controller is connected to the energy extraction winding in the multi-winding multi-tap transformer, and the energy extraction winding in the multi-winding multi-tap transformer adopts a star connection method.

[0024] A fourth aspect of the present invention also provides a power system comprising the series-parallel voltage regulating device described in the third aspect of the present invention.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a voltage regulating module, a voltage regulating control method, a flexible voltage regulating device, and a power system. The voltage regulating module consists of multiple thyristor bridge arms connected in parallel with auxiliary switching circuits. The middle connection point of each bridge arm is the input of the voltage regulating module. One end of the multiple thyristor bridge arms connected in parallel serves as the first output terminal, and the other end serves as the second output terminal. Based on the control signal received from the flexible voltage regulating control method, the multiple thyristor bridge arms are turned on or off to achieve graded regulation of the output voltage. This effectively solves the problems of long voltage regulation response time, inability to cross voltage ranges, and limited number of switching operations caused by the mechanical transmission part of traditional on-load tap changers. It perfectly replaces on-load tap changers for voltage regulation, which is beneficial to improving the voltage regulation performance of on-load tap changers and extending the service life of on-load tap changers.

[0026] This multi-feeder series-parallel flexible voltage regulating device can effectively solve the problem of voltage and current interruption in the voltage regulation process of thyristor-based series-parallel hybrid transformer voltage regulation technology. Moreover, the device can simultaneously realize differentiated automatic, fast, and independent voltage regulation of multiple feeders. Attached Figure Description

[0027] Figure 1 A schematic diagram of a voltage regulating module provided by the present invention; Figure 2 This is a schematic diagram of a single bridge arm main circuit structure design for a voltage regulating module provided by the present invention; Figure 3 This is a schematic diagram of the auxiliary switching circuit structure design for a single bridge arm of a voltage regulating module provided by the present invention; Figure 4 This is a schematic diagram of the overall structural design of a voltage regulating module provided by the present invention; Figure 5 A schematic diagram of a voltage regulation module topology provided by the present invention; Figure 6 This is a schematic diagram of the current path of a voltage regulating module in position 1, as provided by the present invention. Figure 7 A schematic diagram of the current path during voltage regulation module gear switching provided by the present invention; Figure 8 A schematic diagram of the current path during voltage regulation module gear switching provided by the present invention; Figure 9 This is a schematic diagram of the current path of a voltage regulating module in position 2, as provided by the present invention. Figure 10 A flowchart of a voltage regulation control method provided by the present invention; Figure 11 A flowchart of a voltage regulation control method provided by the present invention; Figure 12 A schematic diagram of a single-feeder voltage regulation device topology provided by the present invention; Figure 13 A schematic diagram of a two-feeder voltage regulating device topology provided by the present invention; Figure 14 This is a schematic diagram of a multi-feeder voltage regulation device topology provided by the present invention. Detailed Implementation

[0028] Example 1: Figure 1 This is a schematic diagram of a voltage regulating module provided by the present invention, applicable to series-parallel flexible voltage regulating devices, such as... Figure 1 As shown, the voltage regulating module may include multiple thyristor bridge arms with auxiliary switching circuits, multiple input terminals, a first output terminal, and a second output terminal; one end of the multiple thyristor bridge arms with auxiliary switching circuits connected in parallel serves as the first output terminal, and the other end serves as the second output terminal; one end of each input terminal is connected to the middle connection point of a thyristor bridge arm; the other end of each input terminal is connected to the tap corresponding to each input terminal in an external multi-winding multi-tap transformer; the multiple thyristor bridge arms with auxiliary switching circuits are used to turn on or off based on the received control signal to realize graded regulation of the output voltage of the voltage regulating module.

[0029] It should be noted that in some scenarios, the voltage regulating module can also be referred to as a thyristor-based voltage regulation module with auxiliary switching circuit, a k-arm voltage regulating module, or a k-arm regulating module. This invention addresses the problem that in existing traditional on-load tap changer technology, the mechanical contacts generate large arcs during each closing and opening, potentially damaging the contacts and causing malfunctions in other mechanical transmission components, thus affecting the transformer's voltage regulation performance and shortening its lifespan. The invention uses a thyristor-based k-arm (i.e., multiple thyristor arms) voltage regulating module to replace the traditional mechanical on-load tap changer, eliminating mechanical damage and preserving the transformer's lifespan.

[0030] Traditional on-load tap changers have mechanical transmission parts, which limits the number of times the switch can be operated. This invention uses a thyristor-based k-bridge arm voltage regulating module to replace the traditional mechanical on-load tap changer, eliminating the limitation on the number of switching operations.

[0031] For example, one end of the multiple thyristor bridge arms connected in parallel serves as the first output terminal, and the other end serves as the second output terminal.

[0032] Optionally, each of the thyristor bridge arms includes an upper bridge arm and a lower bridge arm, one end of the upper bridge arm is connected to one end of the lower bridge arm, the other ends of all the upper bridge arms are connected to form a first output terminal, and the other ends of all the lower bridge arms are connected to form a second output terminal.

[0033] For example, the upper bridge arm and the lower bridge arm are connected in series to form each thyristor bridge arm, with one end of the upper bridge arm serving as one end of each thyristor bridge arm and the other end of the lower bridge arm serving as the other end of each thyristor bridge arm.

[0034] Optionally, both the upper bridge arm and the lower bridge arm include a main circuit and an auxiliary switching circuit connected in parallel; the main circuit includes forward and reverse thyristors; the auxiliary switching circuit includes a current-limiting resistor and forward and reverse thyristors connected in series; the upper bridge arm and the lower bridge arm are used to turn on or off the forward and reverse thyristors based on the received control signal, switch the voltage regulation module's range, and realize graded regulation of the voltage regulation module's output voltage.

[0035] In normal operation without gear shifting, at any given time, only one thyristor in the main circuit of the upper bridge arm and only one thyristor in the main circuit of the lower bridge arm are conducting. All thyristors in the auxiliary switching circuits are not conducting. During gear shifting, the main circuits of the exiting and entering bridge arms, along with the auxiliary switching circuits, cooperate to achieve smooth gear shifting. The thyristors in the auxiliary switching circuits have a rated on-state current less than the rated current of the auxiliary switching circuit.

[0036] It should be noted that traditional on-load tap changers have mechanical transmission components, resulting in long voltage regulation response times, slow operation, and the inability to adjust voltage across different ranges, thus hindering dynamic on-load voltage regulation. This invention uses a thyristor-based k-bridge arm voltage regulation module to replace the traditional mechanical on-load tap changer. Thyristors offer fast response times and can achieve cross-range adjustment; due to the fast response time, dynamic adjustment is also possible.

[0037] The voltage regulation technology of a thyristor-based series-parallel hybrid transformer suffers from voltage and current interruption during range switching due to the zero-crossing turn-off characteristic of thyristors. This invention addresses this issue by employing a thyristor-based k-arm voltage regulation module with an auxiliary switching circuit. During range switching, the trigger pulse of the thyristor in the main circuit of the arm about to be deactivated is first canceled, while the current-limiting resistor of the arm about to be activated is simultaneously activated. Then, when the current in the main circuit of the arm about to be deactivated is detected to be 0, the trigger pulse of the thyristor in the auxiliary regulation circuit of the arm about to be activated is canceled. Finally, when the current in the auxiliary regulation circuit of the arm about to be activated is detected to be 0, a trigger pulse is sent to the thyristor in the main circuit of the arm about to be activated, and the current-limiting resistor is deactivated. Through the coordination of the main circuit and the auxiliary switching circuit, the problem of voltage and current interruption during voltage regulation in the thyristor-based series-parallel hybrid transformer voltage regulation technology can be solved.

[0038] Voltage regulation principle: The total n of the k-bridge arm regulation module 2-n+1 speed settings: the more bridge arms there are, the more speed settings there are, and the higher the adjustment precision. During normal operation, at any given time, only one set of the k upper bridge arm main circuit anti-correlated thyristors can be turned on, and only one set of the k lower bridge arm main circuit anti-correlated thyristors can also be turned on. The auxiliary circuit anti-correlated thyristors are all off. Thus, each upper and lower bridge arm has one set of main circuit anti-correlated thyristors turned on, allowing selection of different tap voltages of the multi-tap winding as the output voltage of the adjustment module (i.e., the voltage regulator module). Assume the voltage of the first tap of the multi-tap winding is U1, the voltage of the second tap is U2, and so on, with the voltage of the nth tap being U... k-1 When the anti-correlation thyristors of the upper and lower main circuits of the first bridge arm are simultaneously turned on, and the anti-correlation thyristors of the auxiliary circuits are all turned off, it is equivalent to bypassing the multi-tap winding, and the output voltage of the regulating module is 0V, which is called the 0th position; when the anti-correlation thyristor of the upper main circuit of the first bridge arm is turned on, and at the same time, the anti-correlation thyristor of the lower main circuit of the second bridge arm is turned on, and the anti-correlation thyristors of the auxiliary circuits are all turned off, it is equivalent to connecting the winding voltage of the first tap into the circuit through the thyristor circuit, and the output voltage of the regulating module is U1, which is called the 1st position; when the anti-correlation thyristors of the upper main circuit of the first bridge arm are simultaneously ... it is equivalent to bypassing the multi-tap winding, and the output voltage of the regulating module is 0V, which is called the 1st position; when the anti-correlation thyristors of the upper main circuit of the first bridge arm are simultaneously turned on, it is equivalent to bypassing the multi-tap winding, and the output voltage of the regulating module is U1, which is called the 1st position; when the anti-correlation thyristors of the upper main circuit of the first bridge arm are simultaneously turned on, it is equivalent to bypassing the multi-tap winding, and the output voltage of the regulating module is U1, which is called the 1st position. When the thyristor is turned on, simultaneously, the anti-correlated thyristor of the main circuit of the lower arm of the third bridge arm is turned on, while the anti-correlated thyristors of the auxiliary circuit are all turned off. At this time, it is equivalent to connecting the winding voltage of the second tap into the circuit through the thyristor circuit, and the output voltage of the adjustment module is U2, referred to as position 2. Similarly, when the anti-correlated thyristor of the main circuit of the upper arm of the first bridge arm is turned on, simultaneously, the anti-correlated thyristor of the main circuit of the lower arm of the kth bridge arm is turned on, while the anti-correlated thyristors of the auxiliary circuit are all turned off, it is equivalent to connecting the winding voltage of the nth tap into the circuit through the thyristor circuit, and the output voltage of the adjustment module is U2. k-1 This is called the k-1 gear. Similarly, when the anti-correlated thyristor of the upper main circuit of the second bridge arm is turned on, and simultaneously, the anti-correlated thyristor of the lower main circuit of the first bridge arm is turned on, while the anti-correlated thyristors of the auxiliary circuits are not turned on, it is equivalent to reversing the winding voltage of the first tap into the circuit through the thyristor circuit. The output voltage of the regulating module is -U1, called the -1 gear. By analogy, the output voltage of the regulating module for different combinations of upper and lower bridge arm main circuit thyristor conduction combinations is shown in the following formula:

[0039] Among them, U T The output voltages of the voltage regulation module are represented by U1, U2, U3, ..., U... e These represent the voltage of each segment of a multi-winding, multi-tap transformer, where e is a constant.

[0040] If the i-th main circuit anti-correlation thyristor of the upper bridge arm is turned on, and the j-th main circuit anti-correlation thyristor of the lower bridge arm is turned on, then the corresponding output voltage of the regulating module is:

[0041] Among them, G i This represents the main circuit thyristor of the i-th upper bridge arm in the voltage regulation module. This represents the main circuit thyristor of the j-th lower bridge arm in the voltage regulation module. This represents the voltage of the voltage regulating module when the main circuit thyristor of the i-th upper bridge arm and the main circuit thyristor of the j-th lower bridge arm are turned on. This represents the total voltage of the 0th to j-1th segments of a multi-winding, multi-tap transformer. U0 represents the total voltage of the 0th to i-1th segments of the multi-winding multi-tap transformer, and is the output voltage of the voltage regulating module when U0 is at the 0th tap position.

[0042] For example, one end of the forward and reverse thyristor in the main circuit is connected to one end of the current-limiting resistor, and the other end of the current-limiting resistor is connected to one end of the forward and reverse thyristor in the auxiliary switching circuit. The other end of the forward and reverse thyristor in the main circuit is connected to the other end of the forward and reverse thyristor in the auxiliary switching circuit to form an upper bridge arm or a lower bridge arm.

[0043] Optionally, each of the thyristor bridge arms adopts a modular design, and the modular structure of each thyristor bridge arm is divided into upper and lower layers. The lower layer consists of forward and reverse thyristors for the main circuit, and the upper layer consists of current-limiting resistors and forward and reverse thyristors for the auxiliary switching circuit.

[0044] The forward and reverse thyristors are press-fit thyristors, with a heat sink between adjacent press-fit thyristors. The teeth of the heat sink are vertical. The voltage regulation module also includes a silent fan for dissipating heat from the thyristors.

[0045] Optionally, the voltage regulating module further includes: a first output copper busbar, a second output copper busbar, and a plurality of input copper busbars; the first output copper busbar is connected to the first output terminal, the second output copper busbar is connected to the second output terminal, and each input copper busbar is connected to one of the input terminals; the first and second output copper busbars are used to lead out the first output terminal and the second output terminal; each input copper busbar is used to lead out each of the input terminals.

[0046] It should be noted that the regulating module adopts a compact structural design, consisting of two layers. The lower layer contains the main circuit thyristors, with four press-fit thyristors strung together on each bridge arm. The upper layer contains the current-limiting resistor for the auxiliary switching circuit and two anti-parallel thyristors strung together. Heat sinks are positioned between the press-fit thyristors, with the heat sink teeth pointing vertically. Each thyristor bridge arm is modularly designed with this structure. For k bridge arms, the same k bridge arm modules are arranged sequentially. Thus, a heat dissipation channel is formed between two strings of bridge arms via the vertical heat sink teeth (i.e., multiple thyristor bridge arms in the voltage regulating bridge arm module are arranged sequentially, with a heat dissipation channel formed between two strings of bridge arms via the vertical heat sink teeth). The regulating module is equipped with a silent fan to dissipate heat from the valve body. The input and output terminals of the regulating module are led out through copper busbars.

[0047] Regarding the selection of components for the voltage regulation module, since the auxiliary switching circuit is only activated at the moment of gear switching, and the duration of each switching process is at most 10ms, the characteristic that the peak surge current ITSM of the thyristor is 10~20 times the rated on-state average current IT(AV) is fully utilized. Thyristors with small rated current are selected for the anti-correlated thyristor in the auxiliary switching circuit. For safety, high-order surge-tolerant thyristors can be selected. At the moment of gear switching, the anti-correlated thyristor in the auxiliary switching circuit is designed to operate under 3~5 times the overcurrent condition. For the current-limiting resistor, materials with high resistivity, high temperature resistance, and excellent heat dissipation performance are preferred, with iron-chromium-aluminum alloy (Fe-Cr-Al) being the first choice. These materials can be made into thin strip windings or sheet structures to further reduce the size.

[0048] For example, in terms of the structural design of the regulating module, it is divided into upper and lower layers. The lower layer is the main circuit thyristor, and four press-fit thyristors are connected in a string on one bridge arm, such as... Figure 2 As shown, the upper layer consists of a current-limiting resistor for the auxiliary switching circuit and two anti-parallel thyristors forming a series, as follows: Figure 3 As shown; (the grid represents the heat sink, which dissipates heat from the anti-parallel thyristors through the heat sink fins) The overall structure of the regulating module consists of k bridge arms arranged sequentially, with heat sinks between the pressed thyristors. The teeth of the heat sink fins are vertical, thus forming a heat dissipation channel between two sets of bridge arms via the vertical teeth of the heat sink fins. The regulating module is equipped with a silent fan to dissipate heat from the valve body. The input and output terminals of the regulating module are led out through copper busbars. Figure 4 This is a structural design drawing of a 3-bridge arm voltage regulating module.

[0049] This invention proposes a voltage regulation module based on thyristors and featuring an auxiliary switching circuit. Its core is a voltage regulation circuit (i.e., a voltage regulation module) composed of k bridge arms. The voltage regulation module has k input terminals and two output terminals. Each thyristor bridge arm is divided into upper and lower arms, connected together in the middle. One end of each thyristor bridge arm's input terminal is connected to the corresponding tap of the multi-tap winding on the secondary side of the transformer, thus providing voltage input to the two sets of anti-correlated thyristors. The other end of each input terminal is connected to the middle connection point of one bridge arm. The other ends of all upper bridge arms are connected to form output terminal a, and the other ends of all lower bridge arms are connected to form output terminal b. Specifically, each upper or lower bridge arm consists of two branches: one branch is the main circuit composed of forward and reverse thyristors, and the other branch is an auxiliary switching circuit composed of a current-limiting resistor connected in series with a forward and reverse thyristor. By controlling the on / off state of the thyristors in each bridge arm of the voltage regulation module, the winding taps can be switched, achieving graded adjustment of the output voltage to meet the voltage regulation requirements under different operating conditions.

[0050] For example, this invention proposes a voltage regulation module based on a thyristor with an auxiliary switching circuit, the topology of which is as follows: Figure 5 As shown, its core is a voltage regulating circuit composed of k bridge arms. The voltage regulating module has k input terminals A1, A2, A3...An and two output terminals a and b (i.e., the first output terminal and the second output terminal). The input terminals A1, A2, A3...An are connected to the corresponding taps of the multi-tap winding on the secondary side of the transformer. The input terminals A1, A2, A3...An are internally connected to the middle connection of the upper and lower bridge arms of the k bridge arms. Each thyristor bridge arm of the regulating module is divided into upper and lower bridge arms, which are connected together in the middle and connected to the input terminal to provide voltage input for the upper and lower sets of anti-correlated thyristors. The other ends of all the upper bridge arms are connected to form output terminal a, and the other ends of all the lower bridge arms are connected to form output terminal b. The upper bridge arm of bridge arm 1 is composed of two branches connected in parallel. One branch is the main circuit composed of forward and reverse thyristors G1, and the other branch is an auxiliary switching circuit composed of a current-limiting resistor R1 connected in series with a forward and reverse bypass thyristor G1'. The lower bridge arm of bridge arm 1, as well as the upper and lower bridge arms of bridge arms 2, 3, ..., k, have the same structure as the upper bridge arm of bridge arm 1. During operation, the winding taps can be switched by controlling the on / off state of the thyristors in each bridge arm of the voltage regulating module, thereby achieving graded adjustment of the output voltage to meet the voltage regulation requirements under different operating conditions.

[0051] Voltage regulation process: Taking switching from level 1 to level 2 as an example, before switching, the regulation module is in level 1. At this time, only thyristors G1 and G22 are conducting, and all other thyristors are turned off. The current path is a-G1-winding A1A2-G22-b, as follows. Figure 6 As shown.

[0052] Upon receiving the adjustment command, the first step is to cancel the trigger pulse of thyristor G22 in the main circuit of the second lower bridge arm. Simultaneously, a trigger pulse is sent to thyristor G33' in the auxiliary switching circuit of the third lower bridge arm, putting the current-limiting resistor R33 into operation. At this point, if... Figure 7 As shown, the current flows simultaneously through the thyristor G22 in the main circuit of the second bridge arm, the thyristor G33' in the auxiliary switching circuit of the third bridge arm, and the current-limiting resistor R33. Due to the presence of the current-limiting resistor R33, the current generated in this circuit will not be very large. The second step involves detecting that when the current flowing through the thyristor G22 in the main circuit of the second lower bridge arm is zero, the trigger pulse of the thyristor G33' in the auxiliary switching circuit of the third lower bridge arm is removed. At this time, current flows through the thyristor G33' in the auxiliary switching circuit of the third lower bridge arm and the current-limiting resistor. Figure 8 As shown; The third step involves detecting that when the current G33' flowing through the auxiliary switching circuit of the third bridge arm is 0, a trigger pulse is sent to the main circuit thyristor G33 of the third bridge arm. The current-limiting resistor then exits operation, and current flows through the main circuit thyristor of the third bridge arm. Figure 9 As shown; gear shift complete.

[0053] The k-arm voltage regulating module consists of upper and lower thyristor arms, each divided into upper and lower arms connected together. One end of the input terminal of each thyristor arm is connected to the corresponding tap of the multi-tap winding on the secondary side of the transformer, providing voltage input to the two sets of anti-associated thyristors. The other end of each input terminal is connected to the middle connection point of one arm. The other ends of all upper arms are connected to form output terminal a, and the other ends of all lower arms are connected to form output terminal b. Specifically, each upper or lower arm consists of two branches: one branch is the main circuit composed of forward and reverse thyristors, and the other branch is an auxiliary switching circuit consisting of a current-limiting resistor connected in series with a forward and reverse thyristor. The winding taps can be switched by controlling the on / off state of the thyristors in each arm of the regulating device, achieving graded adjustment of the output voltage to meet the voltage regulation requirements under different operating conditions.

[0054] The k-arm adjustment module has a total of n2-n+1 gears. The more arms there are, the more gears there are, and the higher the adjustment accuracy.

[0055] Example 2: Figure 10 A flowchart of a voltage regulation control method provided by the present invention is applicable to the voltage regulation module described above, such as... Figure 10 As shown, the method may include the following steps 1001 to 1002: In step 1001, the switching position of the voltage regulating module is obtained based on the output voltage requirement of the voltage regulating module.

[0056] In step 1002, based on the switching gear and the current gear of the voltage regulating module, the bridge arm corresponding to the current gear and the bridge arm corresponding to the switching gear are controlled to realize the graded adjustment of the output voltage of the voltage regulating module.

[0057] It should be noted that the voltage regulation control method can be executed through the controller in the aforementioned voltage regulation module. The specific control block diagram is as follows: Figure 11 As shown, firstly, the trigger pulse of the thyristor in the main circuit of the bridge arm that is about to be taken out of operation is canceled, and at the same time, the anti-parallel thyristor in the auxiliary regulation circuit of the bridge arm that is about to be put into operation is turned on, and the current limiting resistor is put into operation; then, when it is detected that the current in the main circuit of the bridge arm that is about to be taken out of operation is 0, the trigger pulse of the anti-parallel thyristor in the auxiliary regulation circuit of the bridge arm that is about to be put into operation is canceled; finally, when it is detected that the current in the anti-parallel thyristor in the auxiliary regulation circuit of the bridge arm that is about to be put into operation is 0, a trigger pulse is sent to the thyristor in the main circuit of the bridge arm that is about to be put into operation, and the current limiting resistor is taken out of operation.

[0058] The above Figure 10 One possible implementation of step 1002 shown may include the following steps S1 to S3: In step S1, based on the switching gear and the current gear of the voltage regulating module, the main circuit of the bridge arm corresponding to the current gear is disconnected, and the auxiliary switching circuit of the bridge arm corresponding to the switching gear is turned on.

[0059] In step S2, based on the current in the main circuit of the bridge arm corresponding to the current gear, the auxiliary switching circuit of the bridge arm corresponding to the switching gear is controlled to be disconnected.

[0060] In step S3, based on the current in the auxiliary switching circuit of the bridge arm corresponding to the switching gear, the main circuit of the bridge arm corresponding to the switching gear is controlled to be turned on.

[0061] It should be noted that the gear switching logic is as follows: During voltage regulation, at the moment of gear switching, the anti-correlated thyristor in the auxiliary switching circuit is turned on, briefly engaging the current-limiting resistor to limit the circulating current during gear switching. The current-limiting resistor functions similarly to the transition resistor in an on-load tap changer. After gear switching is completed, the anti-correlated thyristor in the auxiliary switching circuit is turned off, the current-limiting resistor is deactivated, and the gear switching is complete. The following explanation details the switching process using the example of switching from gear 1 to gear 2.

[0062] First, it should be clarified that when the adjustment module is working in position 1, the thyristor in the main circuit of the upper bridge arm of the first bridge arm and the thyristor in the main circuit of the lower bridge arm of the second bridge arm are turned on, and all other thyristors are turned off; when the adjustment module is working in position 2, the thyristor in the main circuit of the upper bridge arm of the first bridge arm and the thyristor in the main circuit of the lower bridge arm of the third bridge arm are turned on, and all other thyristors are turned off. When the adjustment module is operating at gear 1, and a gear shift command is received to shift from gear 1 to gear 2, it is clear from the above that the thyristor in the main circuit of the second lower bridge arm needs to be turned off, and the thyristor in the main circuit of the third lower bridge arm needs to be turned on. However, during the switching process, if the thyristor in the main circuit of the third lower bridge arm is turned on before the thyristor in the main circuit of the second lower bridge arm is completely turned off, a large circulating current will be generated between the thyristor in the main circuit of the second lower bridge arm, the second tap winding, and the thyristor in the main circuit of the third lower bridge arm, which may burn out the thyristors. To avoid the circulating current generated during the above process, an auxiliary switching circuit is designed. The specific switching procedure is as follows: The first step is to receive the gear shifting command, cancel the trigger pulse of the thyristor in the main circuit of the second lower bridge arm, and at the same time, send a trigger pulse to the thyristor in the auxiliary switching circuit of the third lower bridge arm to put the current limiting resistor into operation. At this time, the current flows through the thyristor in the main circuit of the second lower bridge arm, the thyristor in the auxiliary switching circuit of the third lower bridge arm, and the current limiting resistor. Due to the presence of the current limiting resistor, the current generated in this circuit will not be very large. The second step is to detect that the current flowing through the main circuit thyristor of the second lower bridge arm is 0, and then cancel the trigger pulse of the auxiliary switching circuit thyristor of the third lower bridge arm. At this time, the current flows through the auxiliary switching circuit thyristor of the third lower bridge arm and the current limiting resistor. The third step is to detect that the current flowing through the auxiliary switching circuit thyristor of the lower bridge arm of the third bridge arm is 0. Then, a trigger pulse is sent to the main circuit thyristor of the lower bridge arm of the third bridge arm, and the current limiting resistor is taken out of operation. At this time, the current flows through the main circuit thyristor of the lower bridge arm of the third bridge arm; the gear switching is completed.

[0063] The switching process for other gears follows the same logic: First, the trigger pulse of the thyristor in the main circuit of the bridge arm that is about to be decommissioned is canceled, and at the same time, the anti-parallel thyristor of the bridge arm that is about to be put into operation is turned on, and the current-limiting resistor is put into operation; then, when it is detected that the current in the main circuit of the bridge arm that is about to be decommissioned is 0, the trigger pulse of the thyristor in the auxiliary regulation circuit of the bridge arm that is about to be put into operation is canceled; finally, when it is detected that the current in the thyristor in the auxiliary regulation circuit of the bridge arm that is about to be put into operation is 0, a trigger pulse is sent to the thyristor in the main circuit of the bridge arm that is about to be put into operation, and the current-limiting resistor is taken out of operation.

[0064] When the k-arm regulating module is operating normally, at any given time, only one set of the k upper arm main circuit anti-correlated thyristors can be turned on, and only one set of the k lower arm main circuit anti-correlated thyristors can be turned on as well. The auxiliary circuit anti-correlated thyristors are not turned on. In this way, each upper and lower arm has one set of main circuit anti-correlated thyristors turned on, so different tap voltages of the multi-tap winding can be selected as the output voltage of the regulating module.

[0065] Possible implementations of step S2 above may include the following steps: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the trigger pulses of the forward and reverse thyristors in the auxiliary switching circuit of the bridge arm corresponding to the switching gear are canceled.

[0066] Possible implementations of step S3 above may include the following steps: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the forward and reverse thyristors in the main circuit of the bridge arm corresponding to the gear being switched are activated.

[0067] The above Figure 10 Another possible implementation of step 1002 shown may include the following steps: Based on the switching gear and the current gear of the voltage regulation module, the main circuit of the upper arm corresponding to the current gear is disconnected, and the auxiliary switching circuit of the upper arm corresponding to the switching gear is turned on.

[0068] In the above Figure 10 Before step 1001 shown, the method may further include the following steps: In step 001, the initial gear of the voltage regulating module is obtained based on the start command of the voltage regulating module.

[0069] In step 002, based on the initial gear position of the voltage regulating module, the main circuit of the upper bridge arm corresponding to the initial gear position in the voltage regulating module is turned on, and the main circuit of the lower bridge arm corresponding to the initial gear position is turned on.

[0070] It should be noted that steps 001 to 002 above are the control process for starting the voltage regulating module or the series-parallel flexible voltage regulating device.

[0071] When the k-arm voltage regulation module switches gears, when the adjustment module is working at gear 1, the thyristors in the main circuit of the upper bridge arm of the first bridge arm and the main circuit of the lower bridge arm of the second bridge arm are turned on, and all other thyristors are turned off; when the adjustment module is working at gear 2, the thyristors in the main circuit of the upper bridge arm of the first bridge arm and the main circuit of the lower bridge arm of the third bridge arm are turned on, and all other thyristors are turned off, and so on for other gears.

[0072] Example 3: A third aspect of the present invention also provides a series-parallel flexible voltage regulating device, comprising: an input terminal, a multi-winding multi-tap transformer, multiple voltage regulating modules, multiple series transformers, and multiple output terminals; the input terminal is connected to the three-phase high-voltage windings of the multi-winding multi-tap transformer and the three-phase high-voltage windings of each of the series transformers; the three-phase high-voltage windings of each of the series transformers are also connected to one of the output terminals; each voltage regulating module is respectively connected to the low-voltage winding of one phase of the multi-winding multi-tap transformer and the low-voltage winding of one phase of the series transformer; the input terminal is connected to an external power source, and each of the output terminals is connected to an external load.

[0073] The plurality of voltage regulating modules are the voltage regulating modules described above.

[0074] It should be noted that existing on-load tap changers have mechanical transmission components, resulting in long voltage regulation response times, slow operation, inability to adjust voltage across different ranges, and limited dynamic on-load voltage regulation. To address these issues, this invention discloses a series-parallel flexible voltage regulating device. Its voltage regulation module includes an auxiliary switching circuit, perfectly replacing the on-load tap changer for voltage regulation. It offers advantages such as fast response speed and unlimited adjustment times. Furthermore, it effectively solves the voltage and current interruption problems inherent in thyristor-based series-parallel hybrid transformer voltage regulation technology during the voltage regulation process.

[0075] Traditional on-load tap-changing transformer voltage regulation technology and thyristor-based series-parallel hybrid transformer voltage regulation technology can only achieve voltage regulation of one feeder. However, the series-parallel voltage regulation device designed in this invention can simultaneously achieve differentiated automatic, fast, and independent voltage regulation of 1 to 6 feeders.

[0076] Optionally, the multi-winding multi-tap transformer includes: multiple low-voltage windings; each low-voltage winding includes multiple taps; one end of each of the three-phase high-voltage windings is connected to the input terminal, and the other end of each of the three-phase high-voltage windings is connected to form the neutral point on the high-voltage side of the transformer; each tap of each of the low-voltage windings is connected to an input terminal of one of the voltage regulating modules.

[0077] It should be noted that the voltage of the first tap of the multi-tap winding is U1, the voltage of the second tap is U2, and so on, with the voltage of the nth tap being Uk-1.

[0078] Optionally, the first output terminal of each voltage regulating module is connected to one end of a low-voltage winding of one phase of a series transformer, and the other end of the low-voltage winding of one phase of each series transformer is connected to the second output terminal of each voltage regulating module and grounded; one end of the high-voltage winding of each series transformer is connected to the input terminal, and the other end of the high-voltage winding of each series transformer is connected to one of the output terminals.

[0079] Optionally, the number of voltage regulating modules in the series-parallel flexible voltage regulating device is three times the number of series transformers.

[0080] The thyristor-based series-parallel hybrid transformer voltage regulation technology, in terms of topology, each phase connected to the series transformer consists of three voltage regulation modules connected in series, and the device requires 9 voltage regulation mechanisms. The series-parallel flexible voltage regulation device designed in this invention only requires one voltage regulation module for the three phases, and can achieve almost the same function, thus greatly reducing the overall size of the device.

[0081] Optionally, the voltage regulating device further includes a controller; the controller is connected to the energy extraction winding in the multi-winding multi-tap transformer, and the energy extraction winding in the multi-winding multi-tap transformer adopts a star connection method.

[0082] It should be noted that the series-parallel flexible voltage regulating device is also equipped with an energy harvesting winding. The three-phase energy harvesting winding adopts a star connection method to supply power to the secondary equipment of the device.

[0083] This invention provides a series-parallel flexible voltage regulating device. This device uses the aforementioned regulating module and can effectively solve the problem of voltage and current interruption in the voltage regulation process of thyristor-based series-parallel hybrid transformer voltage regulation technology.

[0084] The series-parallel flexible voltage regulating device includes a multi-winding, multi-tap parallel transformer, 3n regulating modules, and n series transformers, where n can be set from 1 to 6 and can be flexibly adjusted. For the case where n is 1, i.e., single-branch voltage regulation, the three-phase voltage on the power supply side is connected to the input terminal of the flexible voltage regulating device. The input terminal of the flexible voltage regulating device is internally connected to one end of the three-phase high-voltage winding of the multi-tap parallel transformer and one end of the three-phase high-voltage winding of the series transformer. The other end of the three-phase high-voltage winding of the series transformer is the output of the voltage regulating device, which is then connected to the load. The other end of the three-phase high-voltage winding of the multi-winding, multi-tap parallel transformer is connected in three phases, forming the neutral point on the high-voltage side of the transformer. The secondary winding of the multi-winding, multi-tap parallel transformer has multiple taps, with each tap of each phase's secondary winding connected to the input terminal of the corresponding phase's voltage regulating module. The output terminal of this voltage regulating module is connected to the secondary side of the corresponding phase's series transformer. By controlling the on and off of the thyristors in the voltage regulation module, the windings of the secondary windings of the multi-winding, multi-tap parallel transformers that are actually in operation can be selected, thereby coupling the voltages of different parallel transformer secondary windings to the primary side of the series transformer, thus achieving the purpose of regulating the system voltage.

[0085] For a two-branch flexible voltage regulating device, based on the single-branch voltage regulating device, there is an additional set of secondary multi-tap windings, an additional set of voltage regulating modules, and an additional series transformer connected in parallel. These are respectively called multi-tap voltage regulating winding 2, voltage regulating module 2, and series transformer Ts2. The connection method is the same as that of the first branch. The low-voltage side of multi-tap voltage regulating winding 2, voltage regulating module 2, and series transformer Ts2 are connected in sequence. One end of the three-phase high-voltage side of series transformer Ts2 is connected to the input terminal of the device, and the other end is connected to the load on the load side 2.

[0086] For the series-parallel flexible voltage regulating device, the same principle applies to the n-branch voltage regulating device, by adding corresponding secondary multi-tap windings, voltage regulating modules, and series transformers.

[0087] This invention discloses a series-parallel flexible voltage regulating device. Firstly, the power electronic module provides fast adjustment response, unrestricted by the number of switching operations, effectively solving the problems of long response time, inability to cross-voltage range adjustment, and limited switching operations inherent in traditional on-load tap-changing transformers. The voltage regulating module incorporates an auxiliary switching circuit. During range switching, a bypass thyristor quickly connects a current-limiting resistor, resolving the circulating current issue during range switching without causing voltage or current interruption in the load. This effectively addresses the voltage and current interruption problems inherent in thyristor-based series-parallel hybrid transformer voltage regulation technology. The voltage regulating module adopts a modular design, allowing for flexible configuration based on the number of bridge arms (k), enabling plug-and-play operation. The flexible voltage regulating device can be designed as a single-branch or two-branch system, with differentiated, automatic, rapid, and independent voltage adjustment for the two connected branches, effectively suppressing voltage fluctuations and significantly improving power quality. This invention proposes a series-parallel voltage regulating device, the core of which consists of n series transformers, a multi-tap parallel transformer, and 3n k-bridge arm voltage regulating modules, where n can be set from 1 to 6 and can be flexibly adjusted. The multi-tap parallel transformer mainly provides energy to the voltage regulating modules while also participating in voltage regulation; the series transformer mainly couples the output of the voltage regulating module to the line; each group (including phases A, B, and C) of the parallel transformer's secondary multi-tap windings is sequentially connected to a group of k-bridge arm voltage regulating modules (one voltage regulating module for each of phases A, B, and C) and a series transformer, and then connected to a feeder to realize voltage regulation of one feeder. The n series transformers realize differentiated automatic, fast, and independent voltage regulation of n feeders. The k-bridge arm voltage regulating module is an H-bridge type regulating module based on thyristors with auxiliary switching circuit, with k input terminals and 2 output terminals.

[0088] For example, this device uses the aforementioned regulating module, which can effectively solve the problem of voltage and current interruption in the voltage regulation process of thyristor-based series-parallel hybrid transformer voltage regulation technology.

[0089] like Figure 12As shown, the single-branch series-parallel flexible voltage regulator includes a multi-winding, multi-tap parallel transformer Tp, a regulating module, and a series transformer Ts. The three-phase voltages A / B / C on the power supply side are connected to the input terminals A / B / C of the flexible voltage regulator. Internally, the input terminals A / B / C of the flexible voltage regulator are simultaneously connected to one end (A / B / C) of the three-phase high-voltage winding of the multi-tap parallel transformer Tp and one end (A1 / B1 / C1) of the three-phase high-voltage winding of the series transformer Ts. The other end (X1 / Y1 / Z1) of the three-phase high-voltage winding of the series transformer Ts is the output (a1 / b1 / c1) of the voltage regulator, which is then connected to the load side 1. The other ends (X / Y / Z) of the three-phase high-voltage winding of the multi-tap parallel transformer are connected to form a neutral point. The taps of the secondary winding of phase A of the transformer are connected to the input terminals a11 / a12 / a13 of the corresponding phase A adjustment module, and the output terminal aout of the phase A adjustment module is connected to the secondary side a1 of the series transformer of the corresponding phase. The taps of the secondary winding of phase B of the multi-tap parallel transformer are connected to the input terminals b11 / b12 / b13 of the corresponding phase B adjustment module, and the output terminal bout of the phase B adjustment module is connected to the secondary side b1 of the series transformer of the corresponding phase. The taps of the secondary winding of phase C of the multi-tap parallel transformer are connected to the input terminals c11 / c12 / c13 of the corresponding phase C adjustment module, and the output terminal cout of the phase C adjustment module is connected to the secondary side c1 of the series transformer of the corresponding phase. The other three output terminals of the phase A / B / C adjustment modules are connected to form the neutral point of the secondary winding, and are respectively connected to x1 / y1 / z1 of the secondary winding of the series transformer Ts.

[0090] In another embodiment, it can also be a two-branch voltage regulating device, such as... Figure 13As shown, based on the single-branch voltage regulating device, the parallel transformer has an additional set of secondary multi-tap windings, an additional voltage regulating module, and an additional series transformer, respectively called multi-tap voltage regulating winding 2, voltage regulating module 2, and series transformer Ts2. Similar to the first branch connection method, the input terminals A / B / C of the flexible voltage regulating device are simultaneously connected to one end A2 / B2 / C2 of the three-phase high-voltage winding of the series transformer TS2 within the device. The other end X2 / Y2 / Z2 of the three-phase high-voltage winding of the series transformer TS2 is the output a2 / b2 / c2 of the voltage regulating device, which is then connected to the load 2 side. The taps of the A-phase secondary winding of the multi-tap parallel transformer voltage regulating winding 2 are connected to the corresponding input terminals a21 / a22 / a23 of the A-phase regulating module, and the output terminal a2out of the A-phase regulating module is connected to the secondary side a2 of the corresponding phase of the series transformer. The B-phase secondary winding of the multi-tap parallel transformer... The taps of the group are connected to the input terminals b21 / b22 / b23 of the corresponding B-phase adjustment module, and the output terminal b2 of the B-phase adjustment module is connected to the secondary side b2 of the corresponding phase series transformer. The taps of the C-phase secondary winding of the multi-tap parallel transformer are connected to the input terminals c21 / c22 / c23 of the corresponding C-phase adjustment module, and the output terminal c2out of the C-phase adjustment module is connected to the secondary side c2 of the corresponding phase series transformer. The other three output terminals of the a / b / c phase adjustment modules are connected to form the neutral point of the secondary winding of the second branch, and are respectively connected to x2 / y2 / z2 of the secondary winding of the series transformer Ts2. One end X2 / Y2 / Z2 of the three-phase high-voltage side of the series transformer Ts2 is connected to the output terminal of the device, and the other end is connected to the load on the load side 2.

[0091] In another embodiment, for the n-branch voltage regulating device, the same principle applies, by adding corresponding secondary multi-tap windings, voltage regulating modules, and series transformers, such as... Figure 14 As shown.

[0092] In another embodiment, the flexible voltage regulating device is also equipped with an energy harvesting winding. The three-phase energy harvesting winding adopts a star connection method to supply power to the secondary equipment of the device.

[0093] Example 4: A fourth aspect of the present invention also provides a power system comprising the series-parallel flexible voltage regulating device described in the third aspect of the present invention.

[0094] It should be noted that in a series-parallel flexible voltage regulator, for single-branch voltage regulation, the three-phase voltage from the power supply side is connected to the input terminal of the flexible voltage regulator. Internally, the input terminal of the flexible voltage regulator is simultaneously connected to one end of the three-phase high-voltage winding of a multi-tap parallel transformer and one end of the three-phase high-voltage winding of a series transformer. The other end of the three-phase high-voltage winding of the series transformer is the output of the voltage regulator, which is then connected to the load. The other end of the three-phase high-voltage winding of the multi-tap parallel transformer is connected in three-phase connection, forming a neutral point. The secondary winding of the multi-tap parallel transformer has multiple taps, with each tap of each phase's secondary winding connected to the input terminal of the corresponding phase's regulating module. The output terminal of this regulating module is connected to the secondary side of the corresponding phase's series transformer. By controlling the switching on and off of the thyristors in the regulating module, the secondary winding of the multi-tap parallel transformer actually in operation can be selected, thereby coupling the voltages of different parallel transformer secondary windings to the primary side of the series transformer, achieving the purpose of regulating the system voltage.

[0095] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A voltage regulating module, characterized in that, This is applicable to a series-parallel flexible voltage regulating device based on thyristors. The voltage regulating module includes multiple thyristor bridge arms with auxiliary switching circuits, multiple input terminals, a first output terminal, and a second output terminal. One end of the multiple thyristor bridge arms connected in parallel serves as the first output terminal, and the other end serves as the second output terminal; One end of each input terminal is connected to the middle connection point of a thyristor bridge arm; The other end of each input terminal is connected to the tap corresponding to each input terminal in an external multi-winding multi-tap transformer. The plurality of thyristor bridge arms are used to turn on or off based on the received control signals to achieve graded adjustment of the output voltage of the voltage regulation module.

2. The voltage regulating module according to claim 1, characterized in that, Each of the thyristor bridge arms includes an upper bridge arm and a lower bridge arm. One end of the upper bridge arm is connected to one end of the lower bridge arm, and the other ends of all the upper bridge arms are connected to form a first output terminal. The other ends of all the lower bridge arms are connected to form a second output terminal.

3. The voltage regulating module according to claim 2, characterized in that, Both the upper bridge arm and the lower bridge arm include a main circuit and an auxiliary switching circuit connected in parallel; the main circuit includes forward and reverse thyristors; the auxiliary switching circuit includes a current-limiting resistor and forward and reverse thyristors connected in series. The upper bridge arm and the lower bridge arm are used to turn on or off the forward and reverse thyristors based on the received control signal, switch the range of the voltage regulation module, and realize the graded adjustment of the output voltage of the voltage regulation module.

4. The voltage regulating module according to claim 3, characterized in that, When operating normally without shifting gears, at any given moment, only one of the main circuits of the upper bridge arm has its forward and reverse thyristors conducting, and only one of the main circuits of the lower bridge arm has its forward and reverse thyristors conducting. The thyristors of the auxiliary switching circuits of all bridge arms are not conducting.

5. The voltage regulating module according to claim 3, characterized in that, During gear shifting, the main circuit for the outgoing axle arm, the main circuit for the incoming axle arm, and the auxiliary shifting circuit work together to achieve smooth gear shifting.

6. The voltage regulating module according to claim 3, characterized in that, Each thyristor bridge arm adopts a modular design. The modular structure of each thyristor bridge arm is divided into upper and lower layers. The lower layer consists of the forward and reverse thyristors of the main circuit, and the upper layer consists of the current-limiting resistor and forward and reverse thyristors of the auxiliary switching circuit.

7. The voltage regulating module according to claim 6, characterized in that, The forward and reverse thyristors are press-fit thyristors, and a heat sink is placed between two adjacent press-fit thyristors. The teeth of the heat sink are vertical.

8. The voltage regulating module according to claim 3, characterized in that, The forward and reverse thyristors in the auxiliary switching circuit are thyristors whose rated on-current is less than the rated current of the auxiliary switching circuit.

9. The voltage regulating module according to claim 1, characterized in that, The voltage regulation module also includes a silent fan for dissipating heat from the thyristor.

10. The voltage regulating module according to claim 1, characterized in that, The voltage regulation module further includes: a first output copper busbar, a second output copper busbar, and multiple input copper busbars; The first output copper busbar is connected to the first output terminal, the second output copper busbar is connected to the second output terminal, and each input copper busbar is connected to one input terminal. The first output copper bus and the second output copper bus are used to lead out the first output terminal and the second output terminal; Each of the input copper busbars is used to bring out each of the input terminals.

11. A voltage regulation control method, characterized in that, The method applicable to the voltage regulating module according to any one of claims 1-10 includes: Based on the output voltage requirements of the voltage regulation module, the switching range of the voltage regulation module is obtained; Based on the switching gear and the current gear of the voltage regulation module, the bridge arm corresponding to the current gear and the bridge arm corresponding to the switching gear are controlled to realize the graded adjustment of the output voltage of the voltage regulation module.

12. The method according to claim 11, characterized in that, The control of the bridge arm corresponding to the current gear and the bridge arm corresponding to the switched gear based on the switching gear of the voltage regulation module includes: Based on the switching gear and the current gear of the voltage regulation module, the main circuit of the bridge arm corresponding to the current gear is disconnected, and the auxiliary switching circuit of the bridge arm corresponding to the switching gear is turned on. Based on the current in the main circuit of the bridge arm corresponding to the current gear, control the auxiliary switching circuit of the bridge arm corresponding to the switching gear to be disconnected. Based on the current in the auxiliary switching circuit of the bridge arm corresponding to the switching gear, the main circuit of the bridge arm corresponding to the switching gear is controlled to be turned on.

13. The method according to claim 11, characterized in that, The step of controlling the auxiliary switching circuit of the bridge arm corresponding to the switching gear to disconnect based on the current in the main circuit of the bridge arm corresponding to the current gear includes: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the trigger pulses of the forward and reverse thyristors in the auxiliary switching circuit of the bridge arm corresponding to the switching gear are canceled.

14. The method according to claim 11, characterized in that, The step of controlling the main circuit of the bridge arm corresponding to the switching gear to be turned on based on the current in the auxiliary switching circuit of the bridge arm corresponding to the switching gear includes: When the current in the main circuit of the bridge arm corresponding to the current gear is zero, the forward and reverse thyristors in the main circuit of the bridge arm corresponding to the gear being switched are activated.

15. The method according to claim 10, characterized in that, Before determining the switching position of the voltage regulator module based on its output voltage requirement, the method further includes: Based on the start command of the voltage regulating module, the initial gear of the voltage regulating module is obtained; Based on the initial gear position of the voltage regulating module, the main circuit of the upper axle arm corresponding to the initial gear position is turned on, and the main circuit of the lower axle arm corresponding to the initial gear position is turned on.

16. A series-parallel type flexible voltage regulating device, characterized in that, The voltage regulating device includes: an input terminal, a multi-winding multi-tap transformer, multiple voltage regulating modules, multiple series transformers, and multiple output terminals; The input terminal is connected to the three-phase high-voltage winding of the multi-winding multi-tap transformer and the three-phase high-voltage winding of each of the series transformers. The three-phase high-voltage winding of each of the series transformers is also connected to one of the output terminals; Each of the voltage regulating modules is connected to a low-voltage winding of one phase of the multi-winding multi-tap transformer and a low-voltage winding of one phase of the series transformer. Each input terminal is connected to an external power source, and each output terminal is connected to an external load. The plurality of voltage regulating modules are the voltage regulating modules described in any one of claims 1-10.

17. The voltage regulating device according to claim 16, characterized in that, The multi-winding multi-tap transformer includes: multiple low-voltage windings; each of the low-voltage windings includes multiple taps; One end of the three-phase high-voltage winding is connected to the input terminal, and the other end of the three-phase high-voltage winding is connected to form the neutral point on the high-voltage side of the transformer. Each tap of each of the low-voltage windings is connected to an input terminal of one of the voltage regulating modules.

18. The voltage regulating device according to claim 17, characterized in that, The first output terminal of each voltage regulating module is connected to one end of one phase low-voltage winding of one series transformer, and the other end of the three phase low-voltage winding of each series transformer is connected to the second output terminal of each voltage regulating module and grounded. One end of the high-voltage winding in each of the series transformers is connected to the input terminal, and the other end of the high-voltage winding in each of the series transformers is connected to one of the output terminals.

19. The voltage regulating device according to claim 16, characterized in that, The number of voltage regulating modules in the series-parallel flexible voltage regulating device is three times the number of series transformers.

20. The voltage regulating device according to claim 16, characterized in that, The voltage regulating device further includes: a controller; The controller is connected to the energy extraction winding in the multi-winding multi-tap transformer, and the energy extraction winding in the multi-winding multi-tap transformer adopts a star connection method.

21. An electric power system, characterized in that, The power system includes the series-parallel flexible voltage regulating device as described in any one of claims 16-20.

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