High-voltage gain two-stage five-switch bidirectional DC-DC converter

Abstract

The invention relates to the technical field of direct-current converters, in particular to a five-switch bidirectional direct-current converter. The five-switch bidirectional DC-DC converter comprises a DC voltage source module, a high conversion efficiency module, a five-switch bidirectional DC-DC converter module and an MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) control module. Compared with a conventional bidirectional DC-DC converter, the bidirectional DC-DC converter has the characteristic of high voltage gain, and has a wide application prospect, the five-switch bidirectional DC-DC converter is applied, and high voltage gain is obtained through a tap inductor, so that the bidirectional DC-DC converter is widely applied to the fields of DC micro-grids, electric automobiles and the like, and can provide large current, high voltage and high gain. The method plays an important role in the process of constructing an intelligent, green and perfect power system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of DC-DC converter, and particularly relates to a high-voltage gain two-stage five-switch bidirectional DC-DC converter. BACKGROUND

[0002] The current distributed power generation system widely uses new alternative energy to replace traditional energy, and the distributed power supply and the micro-grid composed of the same have become an important part of the current power grid. The DC-DC converter is a key component for connecting the energy storage device and the power system. Unlike the traditional unidirectional converter, the bidirectional DC-DC converter can realize the bidirectional flow of energy, which not only converts the electric energy in the energy storage unit into the voltage suitable for the demand of the power grid, but also reversely transports the excess energy from the load or the power grid to the battery for energy storage under certain conditions. For the charge and discharge regulation of the energy storage system, the battery can be charged and discharged according to the demand. The system can ensure the stable operation of the distributed power generation system and the efficient use of electric energy, and plays a crucial role in the power system. The traditional bidirectional DC-DC converter has the disadvantage of low output voltage gain. If high voltage gain is to be achieved, the size of the output DC voltage usually needs to be changed by adjusting the size of the input DC voltage. However, this will inevitably increase the cost and loss.

[0003] In order to solve the above problems, the present application provides a high-voltage gain two-stage five-switch bidirectional DC-DC converter. SUMMARY

[0004] The present application is used to provide a high-voltage gain two-stage five-switch bidirectional DC-DC converter to solve the problem of high voltage gain that cannot be achieved by the traditional bidirectional DC-DC converter.

[0005] The technical scheme adopted by the present application is as follows: a high-voltage gain two-stage five-switch bidirectional DC-DC converter, comprising a DC voltage source module, a high conversion efficiency module, a five-switch bidirectional DC-DC converter module and a MOSFET control module; the DC voltage source output is connected with the input of the high conversion efficiency module; the output of the high conversion efficiency module is connected with the input of the five-switch bidirectional DC-DC converter, and the output of the five-switch bidirectional DC-DC converter module is connected with the input of the DC voltage source; the DC voltage source is V1 and V2; the high conversion efficiency module comprises a crystal switch tube T1, a crystal switch tube T2, a diode D1, a diode D2, a capacitor C1, a capacitor C2, an inductor L1 and a resistor R1; the five-switch bidirectional DC-DC converter module comprises a crystal switch tube T3, a crystal switch tube T4, a crystal switch tube T5, a crystal switch tube T6, a crystal switch tube T7, a diode D3, a diode D4, a diode D5, a diode D6, a diode D7, a capacitor C3, an inductor L2, an inductor L3, an inductor L4 and a resistor R2.

[0006] The positive pole of the direct current voltage source V1 is connected with the negative pole of the capacitor C1 and the anode of the diode D2 through the resistor R1, the positive pole of the direct current voltage source V2 is connected with the positive pole of the capacitor C3 and the cathode of the diode D6 through the resistor R2, the negative pole of the direct current voltage source V2 is connected with the cathode of the capacitor C3, the anode of the diode D3 and the negative pole of the direct current voltage source V1.

[0007] The MOSFET control module outputs 7 control signals, and the output interfaces are respectively MOS T1, MOS T2, MOS T3, MOS T4, MOS T5, MOS T6 and MOS T7.

[0008] In the high conversion efficiency module, the gate of the crystal switching tube T1 is connected with the T1 output interface of the MOSFET control module, the drain is connected with the positive pole of the voltage source V1, the positive pole of the capacitor C1 and the cathode of the diode D1, and the source is connected with the cathode of the diode D2, the positive pole of the inductor L1 and the anode of the diode D1, the gate of the crystal switching tube T2 is connected with the T2 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D2 and the anode of the inductor L1, and the source is connected with the anode of the diode D2, the cathode of the capacitor C1 and the capacitor C2, the capacitor C1 is connected with the cathode of the resistor R1, the positive pole of the capacitor C2 is connected with the cathode of the inductor L1 and the cathode of the diode D4, and the negative pole is connected with the negative pole of the capacitor C1 and the anode of the diode D3.

[0009] In the five-switch bidirectional DC-DC converter module, the gate of the crystal switching tube T3 is connected with the T3 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L2, the negative pole of the magnetized inductor L4, the positive pole of the inductor L3 and the cathode of the diode D3, and the source is connected with the anode of the diode D3 and the negative pole of the capacitor C2, the gate of the crystal switching tube T4 is connected with the T4 output interface of the MOSFET control module, the drain is connected with the negative pole of L3, and the source is connected with the anode of the diode D4, the gate of the crystal switching tube T5 is connected with the T5 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D4, the positive pole of the capacitor C2 and the negative pole of the inductor L1, and the source is connected with the anode of the diode D5, the gate of the crystal switching tube T6 is connected with the T6 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L3, and the source is connected with the positive pole of the diode D6, the gate of the crystal switching tube T7 is connected with the T7 output interface of the MOSFET control module, the drain is connected with the positive pole of the capacitor C3 and the positive pole of the resistor R2, and the source is connected with the positive pole of the diode D7, the positive pole of the capacitor C3 is connected with the cathode of the diode D6 and the positive pole of the resistor R2, and the negative pole is connected with the negative pole of the capacitor C2 and the anode of the diode D3. BRIEF DESCRIPTION OF DRAWINGS

[0010] To more clearly illustrate the high-voltage gain two-stage five-switch bidirectional DC-DC converter proposed in this invention, further detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments.

[0011] Figure 1 This is a circuit diagram of a high-voltage gain two-stage five-switch bidirectional DC-DC converter according to the present invention.

[0012] Figure 2 for Figure 1 The circuit diagram shows a high-voltage-gain two-stage five-switch bidirectional DC-DC converter in forward buck operation mode 1.

[0013] Figure 3 for Figure 1 The circuit diagram shows a high-voltage-gain two-stage five-switch bidirectional DC-DC converter in forward buck operation mode state 2.

[0014] Figure 4 for Figure 1 The circuit diagram shows a high-voltage-gain two-stage five-switch bidirectional DC-DC converter in forward buck operation mode 3.

[0015] Figure 5 for Figure 1 The circuit diagram shows a high-voltage gain two-stage five-switch bidirectional DC-DC converter in reverse boost mode state 1.

[0016] Figure 6 for Figure 1 The circuit diagram shows a high-voltage-gain two-stage five-switch bidirectional DC-DC converter in reverse boost mode, state 2.

[0017] Figure 7 for Figure 1 The circuit shown is a high-voltage gain two-stage five-switch bidirectional DC-DC converter in reverse boost mode state 3. Specific implementation methods

[0018] The following will be combined with the appendix Figure 1 Appendix Figure 2 Appendix Figure 3 Appendix Figure 4 Appendix Figure 5 Appendix Figure 6 and attached Figure 7 The working mode of the present invention will be described in detail through multiple embodiments. These examples are only some feasible implementation schemes and are not intended to limit the scope of protection of the present invention.

[0019] Figure 1The circuit structure diagram of a high-voltage gain two-stage five-switch bidirectional DC-DC converter of the application is shown, and the specific structure is as follows: a direct current voltage source module, a high conversion efficiency module, a five-switch bidirectional DC-DC converter module, and a MOSFET control module; the direct current voltage source output is connected with the input of the high conversion efficiency module; the output of the high conversion efficiency module is connected with the input of the five-switch bidirectional DC-DC converter, and the output of the five-switch bidirectional DC-DC converter module is connected with the input of the direct current voltage source; the direct current voltage source is V1 and V2; the high conversion efficiency module comprises a crystal switch tube T1, a crystal switch tube T2, a diode D1, a diode D2, a capacitor C1, a capacitor C2, an inductor L1, and a resistor R1; the five-switch bidirectional DC-DC converter module comprises a crystal switch tube T3, a crystal switch tube T4, a crystal switch tube T5, a crystal switch tube T6, a crystal switch tube T7, a diode D3, a diode D4, a diode D5, a diode D6, a diode D7, a capacitor C3, an inductor L2, an inductor L3, an inductor L4, and a resistor R2.

[0020] The positive electrode of the direct current voltage source V1 is connected with the negative electrode of the capacitor C1 and the anode of the diode D2 through the resistor R1, the positive electrode of the direct current voltage source V2 is connected with the positive electrode of the capacitor C3 and the cathode of the diode D6 through the resistor R2, and the negative electrode of the direct current voltage source V2 is connected with the cathode of the capacitor C3, the anode of the diode D3, and the negative electrode of the direct current voltage source V1.

[0021] The MOSFET control module outputs seven control signals, and the output interfaces are MOS tube T1, MOS tube T2, MOS tube T3, MOS tube T4, MOS tube T5, MOS tube T6, and MOS tube T7.

[0022] In the high conversion efficiency module, the gate of the crystal switch tube T1 is connected with the T1 output interface of the MOSFET control module, the drain is connected with the positive electrode of the voltage source V1, the positive electrode of the capacitor C1, and the cathode of the diode D1, and the source is connected with the cathode of the diode D2, the positive electrode of the inductor L1, and the anode of the diode D1; the gate of the crystal switch tube T2 is connected with the T2 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D2 and the positive electrode of the inductor L1, and the source is connected with the anode of the diode D2, the cathodes of the capacitors C1 and C2; the positive electrode of the capacitor C1 is connected with the negative electrode of the resistor R1; the positive electrode of the capacitor C2 is connected with the cathode of the inductor L1 and the cathode of the diode D4, and the negative electrode is connected with the negative electrode of the capacitor C1 and the anode of the diode D3.

[0023] The five-switch bidirectional DC-DC converter module, the gate of the crystal switching tube T3 is connected with the T3 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L2, the negative pole of the magnetized inductor L4 and the positive pole of the inductor L3 and the cathode of the diode D3, and the source is connected with the anode of the diode D3 and the negative pole of the capacitor C2, the gate of the crystal switching tube T4 is connected with the T4 output interface of the MOSFET control module, the drain is connected with the negative pole of L3, and the source is connected with the anode of the diode D4, the gate of the crystal switching tube T5 is connected with the T5 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D4, the positive pole of the capacitor C2 and the negative pole of the inductor L1, and the source is connected with the anode of the diode D5, the gate of the crystal switching tube T6 is connected with the T6 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L3, and the source is connected with the positive pole of the diode D6, the gate of the crystal switching tube T7 is connected with the T7 output interface of the MOSFET control module, the drain is connected with the positive pole of the capacitor C3 and the positive pole of the resistor R2, and the source is connected with the positive pole of the diode D7, the positive pole of the capacitor C3 is connected with the cathode of the diode D6 and the anode of the resistor R2, and the negative pole is connected with the negative pole of the capacitor C2 and the anode of the diode D3, the positive pole of the resistor R2 is connected with the positive pole of the capacitor C3 and the cathode of the diode D6, and the negative pole is connected with the positive pole of the direct current voltage source V2.

[0024] Reference Figure 1 The five-switch bidirectional DC-DC converter of the application is different from the conventional bidirectional DC-DC converter in that the application adopts a tapped inductor to achieve high voltage gain. The five-switch bidirectional DC-DC converter is improved by a tapped inductor from a four-switch converter. The tapped inductor is modeled as an ideal transformer with two windings L2 and L3 and a magnetizing inductor L4 in parallel with the primary winding, which expands the range of voltage gain. From Figure 2 , 3 , 4 and Figure 5 , 6 , 7, it can be seen that the application has two working modes, which are forward buck mode and reverse boost mode.

[0025] When the forward buck mode, the current flows from the direct current voltage source V1 through the resistor R1, the transistor T1 and the inductor L1, so that the energy flows from the direct current voltage source V1 end to the capacitor C2 end, and then flows from the capacitor C2 end through the tapped inductor modeled as an ideal transformer with two windings L2 and L3 and a magnetizing inductor L4 in parallel with the primary winding of the five-switch bidirectional DC-DC converter to the direct current voltage source V2 end. The input direct current voltage V1 can expand the range of high / low voltage gain by changing the turns ratio of the tapped inductor modeled as an ideal transformer with two windings L2 and L3 and a magnetizing inductor L4 in parallel with the primary winding, and the application also has high efficiency. Figure 2 , Figure 3 and Figure 4Three working states in a period T in forward buck mode of the application. Figure 2 State 1 in forward buck mode: transistors T1, T5 and T6 are all turned on, transistor T2 is turned off, the current I1 provided by the direct current voltage source V1, through the resistor R1, through the transistor T1, the inductor L1, the transistor T5, the diode D5, the ideal transformer with two windings L2 and L3 and the magnetizing inductance L4 in parallel with the primary winding modeled by the tapped inductor, the transistor T6, the diode D6, the resistor R2 and the direct current voltage source V2, finally returns to the direct current voltage source V1, in this process, L1 starts to store energy, the current through the inductor L1 gradually increases, and the energy is also transferred from the end of the capacitor C2 to the end of the direct current voltage source V2. Figure 3 State 2 in forward buck mode: transistors T2, T5 and T6 are all turned on, since transistor T1 is turned off, the input direct current voltage V1 end cannot provide energy to the output direct current voltage V2 end, the inductor L1 releases energy, the current I2 flows through the inductor L1 and the transistor T2 to the capacitor C2 and returns to the inductor L1, the current I3 flows through the transistor T5, the diode D5, the ideal transformer with two windings L2 and L3 and the magnetizing inductance L4 in parallel with the primary winding modeled by the tapped inductor, the transistor T6, the diode D6, the resistor R2 and the direct current voltage source V2 to the inductor L1, the energy flows from the inductor L1 to the capacitors C2 and C3, and the inductor L1 current decreases linearly. Figure 4 State 3 in forward buck mode: transistors T2 and T6 are both turned on, the current I4 charges the capacitor C2 through the inductor L1 and the transistor T2, the current I L4 Charges the inductor L2 through the inductor L4, the inductor L3 releases energy, the current I5 flows through the inductor L3, the transistor T6, the diode D6 to the capacitor C3, the diode D3 to the positive electrode of the inductor L3. The currents of the inductors L3 and L1 gradually decrease, and the voltage of the capacitor C3 gradually increases. The voltage V L4 The output direct current voltage V2 also occurs in reverse due to the change in the turns ratio of the ideal transformer with two windings L2 and L3 and the magnetizing inductance L4 in parallel with the primary winding modeled by the tapped inductor. As can be seen from the above description, the voltage gain changes with the change of the turns ratio of the ideal transformer with two windings L2 and L3 and the magnetizing inductance L4 in parallel with the primary winding modeled by the tapped inductor, realizing a high-voltage gain DC-DC converter, which needs to find the appropriate turns ratio of the tapped inductor.

[0026] In the reverse boost mode, energy flows from the DC voltage source V2 end to the DC voltage source V1 end through the tapped inductor modeled ideal transformer with two windings L2 and L3 and magnetizing inductor L4 in parallel with the primary winding. Figure 5 , Figure 6 and Figure 7 are three working states in one period T in the reverse boost mode of the present application. Figure 5 is the reverse boost working mode state 1: transistors T2, T3 and T7 are all turned on, the DC voltage V2 end provides current I6, which flows through transistor T7, diode D7, the tapped inductor modeled ideal transformer with two windings L2 and L3 and magnetizing inductor L4 in parallel with the primary winding, transistor T3 and back to the DC voltage V2, in this process, the current of L4 gradually increases. Inductor L1 releases energy, current I7 charges capacitor C2 through transistor T2. Figure 6 is the reverse boost working mode state 2: transistors T2, T4 and T7 are all turned on, transistor T3 is turned off, the DC voltage source V2 provides current I8, which flows through resistor R2, transistor T7, diode D7, the tapped inductor modeled ideal transformer with two windings L2 and L3 and magnetizing inductor L4 in parallel with the primary winding, inductor L1, transistor T2 and back to the DC voltage source V2, the current I9 flowing through capacitor C2 flows through inductor L1, transistor T2 and back to capacitor C2, in this process, the DC voltage source V2 and capacitor C2 charge inductor L1, the current flowing through inductor L1 gradually increases. Figure 7 is the reverse boost working mode state 3: transistors T1, T4 and T7 are all turned on, transistor T2 is turned off, the DC voltage source V2 provides current I 10 , which flows through resistor R2, transistor T7, diode D7, the tapped inductor modeled ideal transformer with two windings L2 and L3 and magnetizing inductor L4 in parallel with the primary winding, transistor T4, diode D4, inductor L1 and transistor T1 and back to the DC voltage source V2, energy flows from the DC voltage source V2 end to the DC voltage source V1 end, inductor L1 begins to release energy, current I 11The current flows through the inductor L1, the transistor T1, the capacitor C1 and the capacitor C2, the inductor L1 charges the capacitor C1, and the inductor L1 current gradually decreases. In this way, the high-voltage gain needs five-switch bidirectional DC-DC module to obtain higher voltage gain by adjusting the ideal transformer turns ratio of the tapped inductor modeling having two windings L2 and L3 and the magnetizing inductor L4 in parallel with the primary winding, and when the power flow direction is changed from the DC voltage source V1 to the DC voltage source V2 to the DC voltage source V2 to the DC voltage source V1, the current direction of the magnetizing inductor L4 in the ideal transformer of the tapped inductor modeling having two windings L2 and L3 and the magnetizing inductor L4 in parallel with the primary winding can not be changed, which is beneficial to faster dynamic response when the power flow is reversed, and the conversion efficiency of the present application is high, and is suitable for high-power scenarios.

[0027] The above only describes the preferred embodiment of the present application, but is not intended to limit the present application. Any modification and improvement made by those skilled in the art without departing from the principles and spirit of the present application shall be included in the scope of protection of the present application. The scope of protection of the present application shall be subject to the content defined in the claims.

Claims

1. A high voltage gain two-stage five-switch bidirectional DC-DC converter comprising a DC voltage source module, a high conversion efficiency module, a five-switch bidirectional DC-DC converter module, a MOSFET control module; characterized in that: The direct current voltage source output is connected with the high conversion efficiency module input; the high conversion efficiency module output is connected with the five-switch bidirectional DC-DC converter input, and the five-switch bidirectional DC-DC converter module output is connected with the direct current voltage source input; the direct current voltage source is V1, and the direct current voltage source is V2; the high conversion efficiency module comprises a crystal switch tube T1, a crystal switch tube T2, a diode D1, a diode D2, a capacitor C1, a capacitor C2, an inductor L1 and a resistor R1; the five-switch bidirectional DC-DC converter module comprises a crystal switch tube T3, a crystal switch tube T4, a crystal switch tube T5, a crystal switch tube T6, a crystal switch tube T7, a diode D3, a diode D4, a diode D5, a diode D6, a diode D7, a capacitor C3, an inductor L2, an inductor L3, an inductor L4 and a resistor R 2。 2. A high voltage gain two-stage five-switch bidirectional DC-DC converter as claimed in claim 1, characterized in that: The positive pole of the direct current voltage source V1 is connected with the negative pole of the capacitor C1 and the anode of the diode D2 through the resistor R1, the positive pole of the direct current voltage source V2 is connected with the positive pole of the capacitor C3 and the cathode of the diode D6 through the resistor R2, and the negative pole of the direct current voltage source V2 is connected with the cathode of the capacitor C3, the anode of the diode D3 and the negative pole of the direct current voltage source V1.

3. A high voltage gain two-stage five-switch bidirectional DC-DC converter as claimed in claim 1 characterized by: The MOSFET control module outputs 7 control signals, and the output interfaces are MOS T1, MOS T2, MOS T3, MOS T4, MOS T5, MOS T6 and MOS T7 respectively. 7。 4. A high voltage gain two-stage five-switch bidirectional DC-DC converter as claimed in claim 1 characterized by: In the high conversion efficiency module, the gate of the crystal switching tube T1 is connected with the T1 output interface of the MOSFET control module, the drain is connected with the positive pole of the voltage source V1, the positive pole of the capacitor C1 and the cathode of the diode D1, and the source is connected with the cathode of the diode D2, the positive pole of the inductor L1 and the anode of the diode D1, the gate of the crystal switching tube T2 is connected with the T2 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D2 and the anode of the inductor L1, and the source is connected with the anode of the diode D2, the cathode of the capacitor C1 and the capacitor C2, the capacitor C1 is connected with the cathode of the resistor R1, the positive pole of the capacitor C2 is connected with the cathode of the inductor L1 and the cathode of the diode D4, and the negative pole is connected with the negative pole of the capacitor C1 and the anode of the diode D3.

5. A high voltage gain two-stage five-switch bidirectional DC-DC converter as claimed in claim 1 characterized by: In the five-switch bidirectional DC-DC converter module, the gate of the crystal switching tube T3 is connected with the T3 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L2, the negative pole of the magnetized inductor L4, the positive pole of the inductor L3 and the cathode of the diode D3, and the source is connected with the anode of the diode D3 and the negative pole of the capacitor C2, the gate of the crystal switching tube T4 is connected with the T4 output interface of the MOSFET control module, the drain is connected with the negative pole of L3, and the source is connected with the anode of the diode D4, the gate of the crystal switching tube T5 is connected with the T5 output interface of the MOSFET control module, the drain is connected with the cathode of the diode D4, the positive pole of the capacitor C2 and the negative pole of the inductor L1, and the source is connected with the anode of the diode D5, the gate of the crystal switching tube T6 is connected with the T6 output interface of the MOSFET control module, the drain is connected with the negative pole of the inductor L3, and the source is connected with the positive pole of the diode D6, the gate of the crystal switching tube T7 is connected with the T7 output interface of the MOSFET control module, the drain is connected with the positive pole of the capacitor C3 and the positive pole of the resistor R2, and the source is connected with the positive pole of the diode D7, the positive pole of the capacitor C3 is connected with the cathode of the diode D6 and the positive pole of the resistor R2, and the negative pole is connected with the negative pole of the capacitor C2 and the anode of the diode D3.

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