Power supply circuit and power supply method for high voltage DC circuit breakers

Abstract

This invention provides a power supply circuit and method for a high-voltage DC circuit breaker. The power supply circuit includes: a resistor, a first filter inductor, a second filter inductor, a third filter inductor, a fourth filter inductor, a first capacitor, a second capacitor, a third capacitor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first transformer, and a second transformer. This invention effectively solves the problems commonly found in existing power supply topologies, such as narrow zero-voltage switching range of the switching transistors, primary-side circulating current loss, and rectified voltage oscillation. This invention has advantages such as simple circuit structure, wide soft-switching range, low output current ripple, and high conversion efficiency.

Description

Technical Field

[0001] This invention relates to power technology, specifically to a power supply circuit and power supply method for a high-voltage DC circuit breaker. Background Technology

[0002] With the increasing demand for distributed energy sources such as solar and wind power, and the development of power electronics technology, high-voltage direct current (HVDC) transmission systems have experienced rapid development. DC circuit breakers are one of the most important electrical devices in HVDC transmission systems; when a system fault occurs, they can quickly isolate short-circuit faults and prevent further escalation of the fault.

[0003] In a DC circuit breaker, the power circuit typically includes mechanical switches, power electronic devices, surge arresters, etc. To ensure that the DC circuit breaker operates promptly and reliably in the event of a system fault, its control circuit includes drive circuits, detection circuits, etc. These control circuits require a power supply to function properly.

[0004] The power supply method for DC circuit breakers has always been one of the technical challenges in their reliable design. Traditional power supply topologies typically employ a phase-shifted full-bridge structure, which offers advantages such as simple structure, ease of soft switching, and fixed switching frequency. However, when applied to high-voltage DC circuit breakers, it suffers from drawbacks: under light loads, it cannot achieve soft switching, generating severe electromagnetic interference that affects detection and drive circuits, reducing the reliability of the DC circuit breaker's operation; circulating current losses exist on the primary side, exacerbating efficiency degradation and increasing the demand for output filters. Summary of the Invention

[0005] To overcome at least one defect in the power supply of high-voltage DC circuit breakers in the prior art, the present invention provides a power supply circuit for high-voltage DC circuit breakers, comprising: a resistor, a first filter inductor, a second filter inductor, a third filter inductor, a first capacitor, a second capacitor, a third capacitor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first transformer, and a second transformer;

[0006] The first, second, third, and fourth switching transistors constitute an integrated half-bridge inverter circuit and are connected in parallel in the positive and negative output terminals of the DC power supply.

[0007] The first transformer includes: a primary winding and a secondary winding; one end of the primary winding of the first transformer is connected to the connection point of the first and third switching transistors, and the other end of the primary winding of the first transformer is connected to one end of the first capacitor; one end of the secondary winding of the first transformer is connected to the connection point of the cathode of the first rectifier diode and the anode of the third rectifier diode, and the other end of the secondary winding of the first transformer is connected to the connection point of the cathode of the second rectifier diode and the anode of the fourth rectifier diode; the other end of the first capacitor is connected to the connection point between the fourth and second switching transistors, and the other end of the second capacitor is connected to the negative terminal of the DC power supply.

[0008] The cathode of the first rectifier diode is connected to the anode of the third rectifier diode and is connected in series with the first inductor to form a first branch. The cathode of the second rectifier diode is connected to the anode of the fourth rectifier diode and is connected in series with the third inductor to form a second branch. The first branch, the second branch, the resistor, and the third capacitor are connected in parallel.

[0009] The second transformer includes: a primary winding, a first secondary winding, and a second secondary winding; one end of the primary winding of the second transformer is connected to the connection point between the second switching transistor and the fourth switching transistor, and the other end of the primary winding of the second transformer is connected to one end of the second capacitor; one end of the first secondary winding of the second transformer is connected to the connection point between the third rectifier diode and the first inductor, and the other end of the first secondary winding of the second transformer is connected to one end of the second secondary winding, and the other end of the second secondary winding is connected to the connection point between the fourth rectifier diode and the third inductor;

[0010] One end of the first filter inductor, the second filter inductor, and the third filter inductor is connected to one end of the third capacitor as the positive terminal of the output voltage, and the other end of the third capacitor is connected to the anode of the first rectifier diode and the second rectifier diode as the negative terminal of the output voltage.

[0011] Meanwhile, the present invention also provides a power supply method for a high-voltage DC circuit breaker, which uses the aforementioned power supply circuit for a high-voltage DC circuit breaker to supply power to the high-voltage DC circuit breaker.

[0012] The power supply circuit for a high-voltage DC circuit breaker provided by this invention features a second and fourth switching transistor that form a lagging arm switching transistor, enabling zero-voltage switching over a wide load range without exacerbating conduction losses. The secondary-side design with three filter inductors reduces the requirements for the output filter inductor. The dual-transformer design ensures the continuity of power transfer between the primary and secondary sides, eliminates primary-side circulating current losses, and helps reduce the thermal design of the converter, broaden the soft-switching range of the switching transistors, and reduce secondary-side voltage oscillations, thereby improving the converter's conversion efficiency and power density.

[0013] To make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, they can be understood without creative effort.

[0015] Figure 1 A circuit connection diagram of a high-efficiency power supply topology for a high-voltage DC circuit breaker provided by the present invention;

[0016] Figure 2 A simplified equivalent circuit diagram of a high-efficiency power supply topology for a high-voltage DC circuit breaker provided by the present invention;

[0017] Figure 3 Provided by the present invention Figure 2 Schematic diagram of the main working waveforms;

[0018] Figure 4 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0019] Figure 5 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0020] Figure 6 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0021] Figure 7 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0022] Figure 8 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0023] Figure 9 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention;

[0024] Figure 10 This is an equivalent circuit diagram provided in a switching mode in an embodiment of the present invention.

[0025] Symbol explanation:

[0026] V in DC power supply;

[0027] Q1, Q2, Q3, Q4: First switching transistor, second switching transistor, third switching transistor, fourth switching transistor;

[0028] C b C1, C o : First capacitor, second capacitor, third capacitor;

[0029] T FB First transformer;

[0030] T HB Second transformer;

[0031] N FB The primary winding of the first transformer;

[0032] N FB The primary winding of the second transformer;

[0033] n FB The secondary winding of the first transformer;

[0034] n FB The secondary winding of the second transformer;

[0035] D1, D2, D3, D4: First rectifier diode, second rectifier diode, third rectifier diode, fourth rectifier diode;

[0036] L1, L2, L3: First filter inductor, second filter inductor, third filter inductor;

[0037] R: Resistance;

[0038] D: Duty cycle;

[0039] T s : Switching cycle; L k1 :T FB The feeling of leakage;

[0040] L k2 :T HB The leakage sensation;

[0041] L m :T HB Magnetizing inductance;

[0042] C1: Equivalent to a constant voltage source of 0.5V in ;

[0043] Load current: I o . Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] This invention proposes a high-efficiency power supply topology for high-voltage DC circuit breakers, hoping to overcome the shortcomings of existing technologies.

[0046] The present invention provides a power supply circuit for a high voltage DC circuit breaker. The power supply circuit includes: a resistor, a first filter inductor, a second filter inductor, a third filter inductor, a first capacitor, a second capacitor, a third capacitor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first transformer, and a second transformer.

[0047] The first, second, third, and fourth switching transistors constitute an integrated half-bridge inverter circuit and are connected in parallel in the positive and negative output terminals of the DC power supply.

[0048] The first transformer includes: a primary winding and a secondary winding; one end of the primary winding of the first transformer is connected to the connection point of the first and third switching transistors, and the other end of the primary winding of the first transformer is connected to one end of the first capacitor; one end of the secondary winding of the first transformer is connected to the connection point of the cathode of the first rectifier diode and the anode of the third rectifier diode, and the other end of the secondary winding of the first transformer is connected to the connection point of the cathode of the second rectifier diode and the anode of the fourth rectifier diode; the other end of the first capacitor is connected to the connection point between the fourth and second switching transistors, and the other end of the second capacitor is connected to the negative terminal of the DC power supply.

[0049] The cathode of the first rectifier diode is connected to the anode of the third rectifier diode and is connected in series with the first inductor to form a first branch. The cathode of the second rectifier diode is connected to the anode of the fourth rectifier diode and is connected in series with the third inductor to form a second branch. The first branch, the second branch, the resistor, and the third capacitor are connected in parallel.

[0050] The second transformer includes: a primary winding, a first secondary winding, and a second secondary winding; one end of the primary winding of the second transformer is connected to the connection point between the second switching transistor and the fourth switching transistor, and the other end of the primary winding of the second transformer is connected to one end of the second capacitor; one end of the first secondary winding of the second transformer is connected to the connection point between the third rectifier diode and the first inductor, and the other end of the first secondary winding of the second transformer is connected to one end of the second secondary winding, and the other end of the second secondary winding is connected to the connection point between the fourth rectifier diode and the third inductor;

[0051] One end of the first filter inductor, the second filter inductor, and the third filter inductor is connected to one end of the third capacitor as the positive terminal of the output voltage, and the other end of the third capacitor is connected to the anode of the first rectifier diode and the second rectifier diode as the negative terminal of the output voltage.

[0052] This invention provides a novel high-efficiency power supply topology to broaden the zero-voltage switching range of the switching transistor, reduce interference to the control circuit of the DC circuit breaker, eliminate circulating current loss, and reduce output ripple, thereby improving the efficiency of the power supply structure.

[0053] like Figure 1 The diagram shows a high-efficiency power supply topology for a high-voltage DC circuit breaker according to an embodiment of the present invention, including a resistor R, a first filter inductor L1, a second filter inductor L2, a third filter inductor L3, and a first capacitor C. b Second capacitor C1, third capacitor C o The first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4 are, in this embodiment, MOSFETs. The first rectifier diodes D1, D2, D3, and D4 are also present. The first transformer T... FB Second transformer T HB .

[0054] The first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4 constitute an integrated half-bridge inverter circuit, which is connected in parallel in the forward direction to the DC power supply V. in Positive and negative output terminals; first transformer T FB Includes one primary winding N FB and a secondary winding n FB The primary winding N of the first transformer FB One end is connected to the connection point of the first switch Q1 and the third switch Q3, and the other end is connected to the first capacitor C. b One end is connected, the first transformer T FB secondary winding n FBThe two ends are respectively connected to the connection point of the cathode of the first rectifier diode D1 and the anode of the third rectifier diode D3, and the connection point of the cathode of the second rectifier diode D2 and the anode of the fourth rectifier diode D4.

[0055] The second transformer includes one primary winding and two secondary windings. One end of the primary winding is connected to the connection point of the second and fourth switching transistors and the first capacitor, and the other end is connected to one end of the second capacitor. The two ends of the first secondary winding are respectively connected to the cathode of the third rectifier diode, the connection point of the first filter inductor, and the connection point of the second secondary winding and the second filter inductor. The other end of the second secondary winding is connected to the connection point of the anode of the second rectifier diode and the cathode of the fourth rectifier diode. The other end of the first capacitor is connected to the fourth switching transistor, and the other end of the second capacitor is connected to the negative terminal of the DC power supply. The other ends of the first, second, and third filter inductors are connected to one end of the third capacitor as the positive terminal of the output voltage. The other end of the third capacitor is connected to the anode of the first and second rectifier diodes as the negative terminal of the output voltage.

[0056] Specifically, the first switch Q1, the second switch Q2, the third switch Q3, the fourth switch Q4, and the first transformer T FB First capacitor C b This constitutes the topology of a traditional phase-shifted full-bridge DC-DC converter, while the second switch Q2, the fourth switch Q4, and the second transformer T... HB The second capacitor C1 forms a half-bridge topology. Ignoring dead time, the duty cycle of the switching transistor is 0.5. The converter adjusts the phase shift time T... α To achieve the regulation of the output voltage, on the secondary side, the first rectifier diode D1, the second rectifier diode D2, the third rectifier diode D3, the fourth rectifier diode D4 and the first filter inductor L1, the second filter inductor L2, and the third filter inductor L3 constitute a three-inductor filter rectifier unit.

[0057] The present invention also provides a power supply method for a high-voltage DC circuit breaker, which uses the power supply circuit for a high-voltage DC circuit breaker in the embodiments of the present invention to supply power to the high-voltage DC circuit breaker.

[0058] The high-efficiency power supply topology for high-voltage DC circuit breakers proposed in this invention has the following advantages: the lagging arm switch can achieve zero-voltage switching over a wide load range without increasing conduction losses; the secondary-side design with three filter inductors reduces the requirements for output filter inductors; the dual-transformer design ensures the continuity of power transfer between the primary and secondary sides, eliminates primary-side circulating current losses, and helps reduce the thermal design of the converter, widens the soft-switching range of the switch, and reduces secondary-side voltage oscillations, thereby improving the converter's conversion efficiency and power density.

[0059] The following is based on Figure 2 Simplified equivalent circuit, combined with Figures 3 to 10 This invention describes the specific working principle of using the high-efficiency power supply topology of the high-voltage DC circuit breaker provided in this embodiment of the invention.

[0060] Depend on Figure 3 It can be seen that the entire converter has 14 switching modes in one switching cycle, namely [t0~t1], [t1~t2], [t2~t3], [t3~t4], [t4~t5], [t5~t6], [t6~t7], [t7~t8], [t8~t9], [t9~t1 ...4~t5], [t5~t6], [t6~t7], [t7~t8], [t8~t9], [t9~t1], [t2~t3], [t4~t5], [t5~t6], [t6~t7], [t7 10 ]、[t 10 ~t 11 ]、[t 11 ~t 12 ]、[t 12 ~t 13 ]、[t 13 ~t 14 ], where [t0~t7] is the first half of the period, [t7~t 14 The following section provides a detailed analysis of the operation of each switching mode, which is the second half of the cycle.

[0061] In this embodiment, to simplify the analysis, the following assumptions are made: 1) All devices are ideal devices; 2) The parasitic devices of the switching transistor are only considered as the body diode and junction capacitance; 3) T is ignored. FB The magnetizing inductance of the transformer has a leakage inductance of L. kl ;4)T HB The magnetizing inductance is L m Leakage inductance is L k2 5) DC blocking capacitor C1 and output capacitor C o Equivalent to a constant pressure source;

[0062] 6) The values ​​of output inductors L1, L2, and L3 are L o The inductance values ​​of L1, L2, and L3 are large enough to be equivalent to 1 / 3I. o A constant current source.

[0063] Switching mode 1 [t0~t1], corresponding to Figure 4 The first switch Q1, the fourth switch Q4, the second rectifier diode D2, and the third rectifier diode D3 are turned on. This period is the duty cycle period, and the output filter inductor can be mapped to the primary side. The DC blocking capacitor C... b With the voltage and excitation current increasing linearly, the primary and secondary currents remain approximately constant.

[0064] Switching mode 2 [t1~t2], corresponding to Figure 5At time t1, the first switch Q1 is turned off. The junction capacitances of the first switch Q1 and the third switch Q3 are linearly charged and discharged through a constant current source. The voltage at the midpoint of the leading arm, the rectified voltage, and T are all measured. FB The primary and secondary voltages of the transformer begin to decrease linearly. In this mode, the DC blocking capacitor C... b The voltage is considered to be 0.

[0065] Switching mode 3 [t2~t3] (corresponding to the attached) Figure 6 At time t2, the voltage at the midpoint of the leading arm and the voltage of the first transformer T are: FB When the voltage across the primary and secondary sides of the transformer drops to 0, the first switch D1 turns on, and commutation begins between the first switch D1 and the second switch D2. The first transformer T... FB The secondary winding is short-circuited during this period. The first capacitor C... b Voltage applied to L k1 At time t3, i f When (t) drops to 0, the body diode of the third switch Q3 turns on, and the third switch Q3 can achieve zero-voltage turn-on.

[0066] Switching mode 4 [t3~t4] (corresponding to the attached) Figure 7 During this period, the commutation of the first rectifier diode D1 and the second rectifier diode D2 is completed, and only the second transformer T remains. HB Power is transferred to the secondary side.

[0067] Switching mode 5 [t4~t5] (corresponding to the attached) Figure 8 At time t4, the fourth switch Q4 is turned off, and the magnetizing current reaches its maximum value after a linear rise. During this period, the junction capacitances of the second switch Q2 and the fourth switch Q4 are linearly charged and discharged through the constant current source, and the voltage of the fourth rectifier diode D4 linearly decreases to 0.

[0068] Switching mode 6 [t5~t6] (corresponding to the attached) Figure 9 At time t5, the fourth rectifier diode D4 begins to conduct, and the third rectifier diode D3 and the fourth rectifier diode D4 begin commutation. The first transformer T... FB Compared to the second transformation back to the previous T HB With the secondary windings connected in parallel, the junction capacitance and leakage inductance begin to resonate, and the junction capacitances of the second switch Q2 and the fourth switch Q4 charge and discharge. lag (t) The drain-source voltage of the fourth switch rises in a sinusoidal form, and the voltage of the second switch Q2 falls in a sinusoidal form.

[0069] Switching mode 7 [t6~t7] (corresponding to the attached) Figure 10At time t6, Q2 conducts with zero voltage. The third rectifier diode D3 and the fourth rectifier diode D4 are still commutating. The current in the third rectifier diode D3 decreases linearly, while the current in the fourth rectifier diode D4 increases linearly. At time t7, the current in the third rectifier diode D3 drops to zero, while the current in the fourth rectifier diode D4 increases to I. o The converter then enters the second half of the cycle.

[0070] The second half of the cycle [t7~t] 14 The working principle is basically the same as that of the first half of the cycle [t0~t7], except that the current and voltage change in opposite directions, which will not be described again.

[0071] As can be seen from the above description, the high-efficiency power supply topology for high-voltage DC circuit breakers proposed in this invention has the following advantages: half-bridge transformer T HB The increased magnetizing current enhances the inductive energy available to the converter, helping to further expand the zero-voltage switching range. Furthermore, this magnetizing current only flows through the lagging arm switches Q2-Q4, and its average value over half a cycle is zero, thus preventing increased conduction losses. The three-filter inductor secondary design reduces the output filter inductor requirements. The dual-transformer design ensures the continuity of power transfer between the primary and secondary sides, eliminates primary-side circulating current losses, and helps reduce the converter's thermal design, expand the soft-switching range of the switches, and reduce secondary-side voltage oscillations, thereby improving the converter's conversion efficiency and power density.

[0072] Preferred embodiments of the invention have been described above with reference to the accompanying drawings. Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0073] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0074] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0075] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0076] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0077] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A power supply circuit for a high-voltage DC circuit breaker, characterized in that, The power supply circuit includes: a resistor, a first filter inductor, a second filter inductor, a third filter inductor, a first capacitor, a second capacitor, a third capacitor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first transformer, and a second transformer. The first, second, third, and fourth switching transistors constitute an integrated half-bridge inverter circuit and are connected in parallel in the positive and negative output terminals of the DC power supply. The first transformer includes: a primary winding and a secondary winding; one end of the primary winding of the first transformer is connected to the connection point of the first and third switching transistors, and the other end of the primary winding of the first transformer is connected to one end of the first capacitor; one end of the secondary winding of the first transformer is connected to the connection point of the cathode of the first rectifier diode and the anode of the third rectifier diode, and the other end of the secondary winding of the first transformer is connected to the connection point of the cathode of the second rectifier diode and the anode of the fourth rectifier diode; the other end of the first capacitor is connected to the connection point between the fourth and second switching transistors, and the other end of the second capacitor is connected to the negative terminal of the DC power supply. The cathode of the first rectifier diode is connected to the anode of the third rectifier diode and is connected in series with the first inductor to form a first branch. The cathode of the second rectifier diode is connected to the anode of the fourth rectifier diode and is connected in series with the third inductor to form a second branch. The first branch, the second branch, the resistor, and the third capacitor are connected in parallel. The second transformer includes: a primary winding, a first secondary winding, and a second secondary winding; one end of the primary winding of the second transformer is connected to the connection point between the second switching transistor and the fourth switching transistor, and the other end of the primary winding of the second transformer is connected to one end of the second capacitor; one end of the first secondary winding of the second transformer is connected to the connection point between the third rectifier diode and the first inductor, and the other end of the first secondary winding of the second transformer is connected to one end of the second secondary winding, and the other end of the second secondary winding is connected to the connection point between the fourth rectifier diode and the third inductor; One end of the first filter inductor, the second filter inductor, and the third filter inductor is connected to one end of the third capacitor as the positive terminal of the output voltage. The other end of the third capacitor is connected to the anode of the first rectifier diode and the second rectifier diode as the negative terminal of the output voltage. The other end of the second filter inductor is connected to the connection point between the other end of the first secondary winding and one end of the second secondary winding of the second transformer.

2. A power supply method for a high-voltage DC circuit breaker, characterized in that, The method utilizes the power supply circuit for the high-voltage DC circuit breaker as described in claim 1 to supply power to the high-voltage DC circuit breaker.

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