A bidirectional DCDC conversion circuit, a driving method and a bidirectional DC converter

Abstract

The present invention discloses a bidirectional DCDC conversion circuit, a driving method and a bidirectional DC converter, which belong to the field of power electronics technology. The circuit includes a common capacitor branch on the first power supply side, a common capacitor branch on the second power supply side, and a bidirectional buck-boost unit. The two poles at one end of the bidirectional buck-boost unit are connected to the common capacitor branch on the first power supply side to form a first voltage source interface, and the two poles at the other end are connected to the common capacitor branch on the second power supply side to form a second voltage source interface. The method includes a forward process and a reverse process. The converter includes the above-mentioned conversion circuit, a sampling unit, a control unit and a driving unit. The converter adopts a multi-phase staggered parallel form and can be applied to high-power conversion occasions. Compared with the existing DC converter, the converter reduces the number of power devices, improves the utilization rate of power devices, and reduces system costs.

Description

Technical Field

[0001] The present invention belongs to the technical field of power electronics, and in particular relates to a bidirectional DCDC conversion circuit, a driving method and a bidirectional DC converter. Background Art

[0002] In the field of renewable energy power generation, bidirectional DC converters can be used to store the electricity generated by renewable energy in batteries, and then the electricity in the batteries can be sent to the power grid as planned. This can solve the intermittent and unpredictable nature of renewable energy power generation, improve the scheduling and tracking capabilities of renewable energy power generation, and at the same time smooth out the rapid fluctuations in wind and solar power output, reducing the impact on the power grid caused by large-scale sudden changes in wind and solar power output. On the user side, bidirectional DC converters can be used to charge batteries during valley hours and discharge them to the power grid during peak hours, thereby achieving peak shaving and valley filling and obtaining peak-valley price difference profits.

[0003] At present, bidirectional DC converters are usually used Figure 1 The circuit shown can also be further derived Figure 2 and Figure 3 The circuit shown.

[0004] exist Figure 1 to Figure 3 In the circuit shown, a large number of switch tubes are required, such as Figure 1 The single-phase circuit shown requires 8 power tubes. Figure 3 The three-phase staggered parallel topology shown requires 24 power tubes. In addition, during the step-up or step-down process, some power tubes are always disconnected, resulting in a reduced utilization rate of the power tubes. The large number of power tubes and low utilization rate further increase the system cost. At the same time, this topology has the risk of bridge arm direct connection, which reduces the reliability of the system. Reducing the number of power tubes, reducing system costs, and increasing system reliability have become urgent issues to be solved for bidirectional DC converters. Summary of the invention

[0005] In order to solve the above-mentioned defects, the present invention provides a bidirectional DCDC conversion circuit, a driving method and a bidirectional DC converter.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A bidirectional DCDC conversion circuit, comprising:

[0008] A first power supply side common capacitor branch;

[0009] A second power supply side shared capacitor branch;

[0010] A bidirectional buck-boost unit, wherein two poles at one end of the bidirectional buck-boost unit are connected to a common capacitor branch on the first power supply side to form a first voltage source interface, and two poles at the other end are connected to a common capacitor branch on the second power supply side to form a second voltage source interface.

[0011] A further improvement of the present circuit is that: there are N bidirectional buck-boost units, N is a positive integer greater than 1, the N bidirectional buck-boost units are staggered in parallel, and after the staggered parallel connection, the two poles at one end are connected to a shared capacitor branch on the first power supply side, and after the staggered parallel connection, the two poles at the other end are connected to a shared capacitor branch on the second power supply side.

[0012] A further improvement of the circuit is that the bidirectional buck-boost unit comprises a left bridge arm and a right bridge arm, wherein:

[0013] The left bridge arm includes a first switch tube, a third switch tube and an inductor, the emitter of the first switch tube is connected to one end of the inductor, and the other end of the inductor is connected to the collector of the third switch;

[0014] The right bridge arm includes a second switch tube, a fourth switch tube and an inductor. The collector of the second switch tube is connected to one end of the inductor, and the emitter of the fourth switch tube is connected to the other end of the inductor.

[0015] A further improvement of the circuit is that the first switch tube, the second switch tube, the third switch tube and the fourth switch tube are IGBT tubes or MOS tubes.

[0016] A bidirectional DCDC conversion circuit driving method, the method comprising: applied to the above conversion circuit, the method comprises the following forward process:

[0017] Control the left bridge arm of P bidirectional buck-boost units to be turned on and the right bridge arm to be turned off, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer;

[0018] Control the left bridge arm of P bidirectional buck-boost units to be turned off and the right bridge arm to be turned on, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P;

[0019] By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode.

[0020] A further improvement of this method is that it also includes the following reverse process:

[0021] Control the right bridge arms of P bidirectional buck-boost units to be turned on and the left bridge arms to be turned off to provide energy to the load, wherein the phase difference between the right bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer;

[0022] Control the right bridge arm of P bidirectional buck-boost units to be turned off and the left bridge arm to be turned on to provide energy to the load, wherein the phase difference between the right bridge arm driving signals of the P bidirectional buck-boost units is 360° / P;

[0023] By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode.

[0024] A bidirectional direct current converter, comprising:

[0025] The above conversion circuit;

[0026] A sampling unit, used for sampling the state of the above-mentioned conversion circuit and sending the sampled data to the control unit;

[0027] A control unit, used to generate a signal that can execute the above conversion circuit driving method, and also used to determine whether the conversion circuit state exceeds a threshold value, and if so, block the signal of the conversion circuit driving method;

[0028] The driving unit is used to amplify the power of the signal of the conversion circuit driving method to drive the above conversion circuit.

[0029] The further improvement of the converter is that:

[0030] The communication unit is used for communicating with the control unit.

[0031] A further improvement of the converter is that the conversion circuit state is at least one of the output voltage and output current of the conversion circuit.

[0032] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0033] The present invention provides a bidirectional DCDC conversion circuit, a driving method and a bidirectional DC converter. The converter adopts a multi-phase staggered parallel connection form and can be applied to high-power conversion occasions. Compared with the existing DC converter, the converter reduces the number of power devices, improves the utilization rate of power devices, and reduces the system cost. At the same time, the power inductor is connected in series in the switch bridge arm of the converter, which reduces the risk of bridge arm direct connection and enhances the system reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly explain the operating principle and technical solutions of the present invention, the following briefly introduces the drawings required for the operating principle and the technologies used. Obviously, the drawings described below are only some operating examples of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of a bidirectional DCDC conversion circuit structure in the prior art;

[0036] Figure 2 A schematic diagram of a derived structure of a bidirectional DCDC conversion circuit in the prior art;

[0037] Figure 3 It is a schematic diagram of another bidirectional DCDC conversion circuit derivative structure in the prior art;

[0038] Figure 4 A schematic diagram of a specific implementation of a bidirectional DCDC conversion circuit proposed in the present invention;

[0039] Figure 5 A circuit topology diagram of a specific implementation of the bidirectional DCDC conversion circuit proposed by the present invention;

[0040] Figure 6 A schematic diagram of the structure of a bidirectional DC converter proposed by the present invention;

[0041] Figure 7 A schematic diagram of the topology of a single bidirectional buck-boost unit of the bidirectional DCDC conversion circuit proposed by the present invention;

[0042] Figure 8 A schematic diagram of a first working state of a single bidirectional buck-boost unit of the bidirectional DCDC conversion circuit proposed by the present invention;

[0043] Fig. 9 This is a schematic diagram of the second working state of a single bidirectional buck-boost unit of the bidirectional DCDC conversion circuit proposed by the present invention. DETAILED DESCRIPTION

[0044] like Figure 4 As shown, the present invention provides a bidirectional DCDC conversion circuit, comprising: a first power supply side shared capacitor branch, a second power supply side shared capacitor branch, and a bidirectional buck-boost unit.

[0045] Among them, the two poles at one end of the bidirectional buck-boost unit are connected to the shared capacitor branch on the first power supply side to form a first voltage source interface, and the two poles at the other end are connected to the shared capacitor branch on the second power supply side to form a second voltage source interface.

[0046] Furthermore, there are N bidirectional buck-boost units, where N is a positive integer greater than 1. The N bidirectional buck-boost units are connected in parallel in an interlaced manner. After the interlaced parallel connection, the two poles at one end are connected to a common capacitor branch on the first power supply side, and after the interlaced parallel connection, the two poles at the other end are connected to a common capacitor branch on the second power supply side.

[0047] Based on the above-mentioned driving method of a bidirectional DCDC conversion circuit, the method includes a forward process and a reverse process;

[0048] Forward process: control the left bridge arm of P bidirectional buck-boost units to be turned on and the right bridge arm to be turned off, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer;

[0049] Control the left bridge arm of P bidirectional buck-boost units to be turned off and the right bridge arm to be turned on, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P;

[0050] By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode.

[0051] Reverse process: control the right bridge arm of P bidirectional buck-boost units to be turned on and the left bridge arm to be turned off, wherein the phase difference between the right bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer;

[0052] Control the right bridge arm of P bidirectional buck-boost units to be turned off and the left bridge arm to be turned on, wherein the phase difference between the right bridge arm driving signals of the P bidirectional buck-boost units is 360° / P;

[0053] By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode.

[0054] A bidirectional DC converter based on the above bidirectional DCDC conversion circuit and driving method includes the above conversion circuit, a sampling unit, a communication unit, a control unit and a driving unit.

[0055] Among them, the sampling unit is used to sample the state of the above-mentioned conversion circuit and send the sampled data to the control unit; the control unit is used to generate a signal that can execute the above-mentioned conversion circuit driving method, and is also used to determine whether the state of the conversion circuit exceeds the threshold. If so, the signal of the conversion circuit driving method is blocked; the driving unit is used to power amplify the signal of the conversion circuit driving method and drive the above-mentioned conversion circuit, and the communication unit communicates with the control unit.

[0056] The above circuits, methods and converters are the concepts and processing ideas of the present invention. The drive protection method proposed by the present invention is described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] Please refer to Figure 4 , a bidirectional DCDC conversion circuit, the circuit comprising:

[0058] A first voltage source interface and a second voltage source interface;

[0059] A first voltage source side shared capacitor and a second voltage source side shared capacitor, wherein the first voltage source side shared capacitor and the second voltage source side shared capacitor are connected to the first voltage source interface and the second voltage source interface respectively;

[0060] The first bidirectional buck-boost unit, the second bidirectional buck-boost unit, and the third bidirectional buck-boost unit are all connected to both ends of the shared capacitor on the first voltage source side, and are all connected to the shared capacitor on the second voltage source side.

[0061] The first bidirectional buck-boost unit includes an IGBT tube Q1, an IGBT tube Q2, an IGBT tube Q3, an IGBT tube Q4, and an inductor L1;

[0062] The second bidirectional buck-boost unit includes an IGBT tube Q5, an IGBT tube Q6, an IGBT tube Q7, an IGBT tube Q8, and an inductor L2;

[0063] The third bidirectional buck-boost unit includes IGBT tube Q9, IGBT tube Q 10 、IGBT tube Q 11 、IGBT tube Q 12 , inductor L3;

[0064] In the first bidirectional buck-boost unit, the collector of the IGBT tube Q1 is connected to the positive electrode of the first voltage source interface, the emitter of the IGBT tube Q1 is connected to the collector of the IGBT tube Q2, and the emitter of the IGBT tube Q2 is connected to the negative electrode of the second voltage source interface; the emitter of the IGBT tube Q3 is connected to the negative electrode of the first voltage source interface, the collector of the IGBT tube Q3 is connected to the emitter of the IGBT tube Q4, and the collector of the IGBT tube Q4 is connected to the positive electrode of the second voltage source interface; the connection point of the IGBT tube Q1 and the IGBT tube Q2 is connected to one end of the inductor L1, and the connection point of the IGBT tube Q3 and the IGBT tube Q4 is connected to the other end of the inductor L1.

[0065] In the second bidirectional buck-boost unit, the collector of the IGBT tube Q5 is connected to the positive electrode of the first voltage source interface, the emitter of the IGBT tube Q5 is connected to the collector of the IGBT tube Q6, and the emitter of the IGBT tube Q6 is connected to the negative electrode of the second voltage source interface; the emitter of the IGBT tube Q7 is connected to the negative electrode of the first voltage source interface, the collector of the IGBT tube Q7 is connected to the emitter of the IGBT tube Q8, and the collector of the IGBT tube Q8 is connected to the positive electrode of the second voltage source interface; the connection point of the IGBT tube Q5 and the IGBT tube Q6 is connected to one end of the inductor L2, and the connection point of the IGBT tube Q7 and the IGBT tube Q8 is connected to the other end of the inductor L2.

[0066] The collector of the third bidirectional buck-boost unit IGBT tube Q9 is connected to the positive electrode of the first voltage source interface, and the emitter of the IGBT tube Q 10 The collector of IGBT tube Q 10 The emitter of the IGBT is connected to the negative electrode of the second voltage source interface; 11 The emitter of the IGBT is connected to the negative electrode of the first voltage source interface, and the IGBT tube Q 11 The collector and IGBT tube Q 12 The emitter of IGBT is connected to 12 The collector of is connected to the positive electrode of the second voltage source interface; IGBT tube Q9 and IGBT tube Q 10 The connection point is connected to one end of the inductor L1, and the IGBT tube Q 11 and IGBT tube Q 12 The connection point is connected to the other end of inductor L3.

[0067] IGBT tubes Q1 and Q2, Q3 and Q4, Q5 and Q6, Q7 and Q8, Q9 and Q 10 , Q 11 and Q 12 Work complementary to each other.

[0068] IGBT tubes Q1 and Q3, Q5 and Q7, Q9 and Q 11 The drives are identical, but the phases are staggered by 120 degrees.

[0069] The IGBT tubes Q2 and Q4, Q6 and Q8, Q 10 and Q 12 The drives are also identical, with a phase shift of 120 degrees.

[0070] refer to Figure 5 Another embodiment of the present application provides a bidirectional DC converter, comprising: a sampling unit, a driving unit, a control unit, a communication unit, and a bidirectional DCDC conversion circuit applied to the previous embodiment; wherein:

[0071] One side of the bidirectional DCDC conversion circuit serves as one side of the bidirectional DC converter, and is connected to two levels of the battery device or the DC bus correspondingly; the other side of the bidirectional DCDC conversion circuit serves as the other side of the bidirectional DC converter, and is connected to two levels of the battery device or the DC bus correspondingly;

[0072] The sampling unit detects the voltage and current of each side of the three-way DCDC conversion circuit, and sends the detection result to the control unit;

[0073] The communication unit sends information such as external control signals to the control unit;

[0074] The control unit combines the information uploaded by the sampling unit and the communication unit to comprehensively judge the current working state of the bidirectional DC converter and gives a driving signal to the driving unit;

[0075] The driving unit amplifies the power of the driving signal output by the control unit and sends the amplified ...

[0076] The working process of driving the above circuit is as follows:

[0077] Taking a certain phase as an example, the circuit working process is described. The circuit is divided into two working processes, the forward working process, that is, the energy is transferred from C1 to C2, and the reverse working process, that is, the energy is transferred from C2 to C1.

[0078] 1. Positive working process:

[0079] 1) Switches Q1 and Q3 are turned on, while Q2 and Q4 are turned off. Inductor L1 stores energy, and capacitor C2 provides energy to the load. At this time, the circuit diagram is as follows: Figure 8 As shown;

[0080] 2) Switches Q1 and Q3 are turned off, while Q2 and Q4 are turned on. Inductor L1 releases energy, which charges capacitor C2 and supplies power to the load. The circuit diagram is as follows: Fig. 9 shown.

[0081] Circuit ratio:

[0082] From the above analysis, we can see that by controlling the on / off time of Q1 and Q3, we can control the charging and discharging time of the inductor, and thus the boost ratio. According to the volt-second balance of the inductor, we can get:

[0083] V in T on =V out T off

[0084] get:

[0085]

[0086] Among them, V out is the output voltage, V in is the input voltage, D is the duty cycle, when D is greater than 0.5, M is greater than 1, the circuit exhibits a boost function, when D is less than 0.5, M is less than 1, the circuit exhibits a buck function.

[0087] Reverse working process:

[0088] When working in reverse, you only need to swap the control signals of Q1, Q3 and Q2, Q4.

[0089] The embodiments described above are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A bidirectional DCDC conversion circuit, comprising: A first power supply side common capacitor branch; A second power supply side shared capacitor branch; A bidirectional buck-boost unit, wherein the two poles at one end of the bidirectional buck-boost unit are connected to a common capacitor branch on the first power supply side to form a first voltage source interface, and the two poles at the other end are connected to a common capacitor branch on the second power supply side to form a second voltage source interface; the bidirectional buck-boost unit is N, N is a positive integer greater than 1, and the N bidirectional buck-boost units are staggered in parallel. After the staggered parallel connection, the two poles at one end are connected to the common capacitor branch on the first power supply side, and after the staggered parallel connection, the two poles at the other end are connected to the common capacitor branch on the second power supply side; the bidirectional buck-boost unit includes a left bridge arm and a right bridge arm, wherein: the left The bridge arm includes a first switch tube, a third switch tube and an inductor, the emitter of the first switch tube is connected to one end of the inductor, and the other end of the inductor is connected to the collector of the third switch; the right bridge arm includes a second switch tube, a fourth switch tube and an inductor, the collector of the second switch tube is connected to one end of the inductor, and the emitter of the fourth switch tube is connected to the other end of the inductor; the first switch tube, the second switch tube, the third switch tube and the fourth switch tube are IGBT tubes or MOS tubes; it is characterized in that the bidirectional buck-boost unit includes a first bidirectional buck-boost unit, a second bidirectional buck-boost unit, and a third bidirectional buck-boost unit, The first bidirectional buck-boost unit includes IGBT tube Q1, IGBT tube Q2, IGBT tube Q3, IGBT tube Q4, and inductor L1; the second bidirectional buck-boost unit includes IGBT tube Q5, IGBT tube Q6, IGBT tube Q7, IGBT tube Q8, and inductor L2; the third bidirectional buck-boost unit includes IGBT tube Q9, IGBT tube Q 10 、IGBT tube Q 11 、IGBT tube Q 12 , inductor L3; In the first bidirectional buck-boost unit, the collector of the IGBT tube Q1 is connected to the positive electrode of the first voltage source interface, the emitter of the IGBT tube Q1 is connected to the collector of the IGBT tube Q2, and the emitter of the IGBT tube Q2 is connected to the negative electrode of the second voltage source interface; the emitter of the IGBT tube Q3 is connected to the negative electrode of the first voltage source interface, the collector of the IGBT tube Q3 is connected to the emitter of the IGBT tube Q4, and the collector of the IGBT tube Q4 is connected to the positive electrode of the second voltage source interface; the connection point of the IGBT tube Q1 and the IGBT tube Q2 is connected to one end of the inductor L1, and the connection point of the IGBT tube Q3 and the IGBT tube Q4 is connected to the other end of the inductor L1; In the second bidirectional buck-boost unit, the collector of the IGBT tube Q5 is connected to the positive electrode of the first voltage source interface, the emitter of the IGBT tube Q5 is connected to the collector of the IGBT tube Q6, and the emitter of the IGBT tube Q6 is connected to the negative electrode of the second voltage source interface; the emitter of the IGBT tube Q7 is connected to the negative electrode of the first voltage source interface, the collector of the IGBT tube Q7 is connected to the emitter of the IGBT tube Q8, and the collector of the IGBT tube Q8 is connected to the positive electrode of the second voltage source interface; the connection point of the IGBT tube Q5 and the IGBT tube Q6 is connected to one end of the inductor L2, and the connection point of the IGBT tube Q7 and the IGBT tube Q8 is connected to the other end of the inductor L2; The collector of the third bidirectional buck-boost unit IGBT tube Q9 is connected to the positive electrode of the first voltage source interface, and the emitter of the IGBT tube Q 10 The collector of IGBT tube Q 10 The emitter of the IGBT is connected to the negative electrode of the second voltage source interface; 11 The emitter of the IGBT is connected to the negative electrode of the first voltage source interface, and the IGBT tube Q 11 The collector and IGBT tube Q 12 The emitter of IGBT is connected to 12 The collector of is connected to the positive electrode of the second voltage source interface; IGBT tube Q9 and IGBT tube Q 10 The connection point is connected to one end of the inductor L1, and the IGBT tube Q 11 and IGBT tube Q 12 The connection point is connected to the other end of the inductor L3; Among them, IGBT tubes Q1 and Q3, Q5 and Q7, Q9 and Q 11 The drives are the same, but the phases are staggered by 120 degrees; IGBT tubes Q2 and Q4, Q6 and Q8, Q 10 and Q 12 The drives are identical, but the phases are staggered by 120 degrees.

2. A bidirectional DCDC conversion circuit driving method, characterized in that: Applied to the conversion circuit as claimed in claim 1, the method comprises the following forward process: Control the left bridge arm of P bidirectional buck-boost units to be turned on and the right bridge arm to be turned off, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer; Control the left bridge arm of P bidirectional buck-boost units to be turned off and the right bridge arm to be turned on, wherein the phase difference between the left bridge arm drive signals of the P bidirectional buck-boost units is 360° / P; By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode. Among them, V out is the output voltage, V in is the input voltage, D is the duty cycle, when D is greater than 0.5, M is greater than 1, the circuit exhibits a boost function, when D is less than 0.5, M is less than 1, the circuit exhibits a buck function.

3. A bidirectional DCDC conversion circuit driving method according to claim 2, characterized in that: The reverse process is also included as follows: Control the right bridge arms of P bidirectional buck-boost units to be turned on and the left bridge arms to be turned off, wherein the phase difference between the right bridge arm drive signals of the P bidirectional buck-boost units is 360° / P, where P is a positive integer; Control the right bridge arm of P bidirectional buck-boost units to be turned off and the left bridge arm to be turned on, wherein the phase difference between the right bridge arm driving signals of the P bidirectional buck-boost units is 360° / P; By controlling the duty cycle of the left bridge arm of the bidirectional buck-boost unit, the converter can be operated in boost or buck mode. When the duty cycle is greater than 0.5, it works in buck mode; when the duty cycle is less than 0.5, it works in boost mode.

4. A bidirectional DC converter, characterized in that: include: The conversion circuit as claimed in claim 1; A sampling unit, used for sampling the state of the conversion circuit as claimed in claim 1, and sending the sampled data to the control unit; A control unit, used to generate a signal that can execute the conversion circuit driving method according to claim 2 or 3, and also used to determine whether the conversion circuit state exceeds a threshold value, and if so, block the signal of the conversion circuit driving method; A driving unit is used to power amplify the signal of the conversion circuit driving method to drive the conversion circuit as claimed in claim 1.

5. A bidirectional DC converter according to claim 4, characterized in that: Also includes: The communication unit is used for communicating with the control unit.

6. A bidirectional DC converter according to any one of claims 4 or 5, characterized in that: The conversion circuit state is at least one of the output voltage and output current of the conversion circuit.

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