Bidirectional DC converter circuit
By designing a bidirectional DC converter circuit including charging circuit and buck circuit, the problems of existing circuit complexity and high production cost are solved, and the bidirectional conversion of voltage and the reduction of production cost are achieved.
Patent Information
- Application Number
- CN202421000009.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-10
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-05-10
AI Technical Summary
The existing bidirectional DC converter circuits are relatively complex and increase production costs.
A bidirectional DC converter circuit including a charging circuit and a buck circuit is designed, and the bidirectional conversion of voltage is achieved using components such as input capacitors, inductors, diodes, output capacitors, switch tubes and voltage dividers.
The circuit structure is simplified, production costs are reduced, while taking into account the simplicity of bidirectional functions and control.
Smart Images
Figure CN222484551U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of bidirectional direct current converters, in particular to a bidirectional direct current converter circuit. Background Art
[0002] With the rapid development of new energy vehicles, a large number of charging piles have been established. Due to the lack of unified standards in various countries, two main types of charging piles have been formed on the market, one with an output voltage of 200-500Vdc and the other with an output voltage of 200-750Vdc. The domestic market is mainly dominated by an output voltage of 200-750Vdc, while some foreign markets are dominated by an output voltage of 200-500Vdc. Domestic car manufacturers export electric vehicles to foreign countries, mainly with domestic matching, but need to adapt to foreign charging piles. Therefore, some exported models need to be equipped with a DC converter that converts the voltage from 200-500Vdc to 500V-750Vdc.
[0003] When exporting electric vehicles to foreign countries for charging, a DC converter needs to be added between the charging pile and the car battery. According to the charging process of the charging pile, the battery voltage must be detected at the port before the charging device outputs. In order to make the monitored battery voltage between 200 and 500 Vdc, the high-voltage battery with a voltage level between 500 and 750 Vdc must be stepped down before it can be used in conjunction. Therefore, the DC converter needs to set up a bidirectional circuit to charge the car. However, the existing bidirectional circuit is relatively complex, which increases production costs.
[0004] The above defects need to be solved urgently. Utility Model Content
[0005] In order to solve the problem that the bidirectional circuit of the existing DC converter is relatively complex and the production cost is increased, the utility model provides a bidirectional DC converter circuit.
[0006] The technical solution of the utility model is as follows:
[0007] A bidirectional DC converter circuit comprises a charging circuit and a step-down circuit, wherein the charging circuit comprises an input capacitor C1, an inductor L1, a diode D1, and an output capacitor C2, wherein one end of the inductor L1 is connected to one end of the input capacitor C1, the other end of the inductor L1 is connected to one end of the diode D1, the other end of the diode D1 is connected to one end of the output capacitor C2, and the other end of the input capacitor C1 and the other end of the output capacitor C2 are both grounded;
[0008] The step-down circuit includes a switch and a reference circuit. The reference circuit includes a switch tube Q2. One end of the switch is respectively connected to the other end of the diode D1 and one end of the output capacitor C2. The other end of the switch is connected to one end of the switch tube Q2. The other end of the switch tube Q2 is respectively connected to one end of the inductor L1 and one end of the input capacitor C1.
[0009] According to the above scheme of the utility model, the step-down circuit also includes a first voltage divider circuit and a second voltage divider circuit, the input end of the first voltage divider circuit and the input end of the second voltage divider circuit are both connected to the other end of the switch, and the output end of the first voltage divider circuit and the output end of the second voltage divider circuit are both connected to one end of the switch tube Q2.
[0010] Furthermore, the switch tube Q2 is a MOS tube, the D pole of the switch tube Q2 is connected to the output end of the first voltage divider circuit, the G pole of the switch tube Q2 is connected to the output end of the second voltage divider circuit, and the S pole of the switch tube Q2 is respectively connected to one end of the inductor L1 and one end of the input capacitor C1.
[0011] According to the utility model of the above scheme, the reference circuit also includes a voltage regulator diode Z1 and a resistor R3. The cathode of the voltage regulator diode Z1 and one end of the resistor R3 are connected to the D pole of the switch tube Q2. The anode of the voltage regulator diode Z1, the other end of the resistor R3, and the S pole of the switch tube Q2 are respectively connected to one end of the input capacitor C1 and one end of the inductor L1.
[0012] According to the above solution of the utility model, the switch tube Q2 is an N-channel enhancement type MOS tube.
[0013] According to the utility model of the above scheme, the charging circuit also includes a switch tube Q1, a resistor R1, and a resistor R2. One end of the switch tube Q1 is respectively connected to the other end of the inductor L1 and one end of the diode D1, the other end of the switch tube Q1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the resistor R2, and the other end of the resistor R2 is grounded.
[0014] Furthermore, the switch tube Q1 is a MOS tube, the D pole of the switch tube Q1 is connected to the other end of the inductor L1 and one end of the diode D1 respectively, the G pole of the switch tube Q1 is connected to one end of the resistor R1, and the S pole of the switch tube Q1 is grounded.
[0015] According to the above solution of the utility model, the switch tube Q1 is an N-channel enhancement type MOS tube.
[0016] According to the utility model of the above solution, the switch is a relay.
[0017] According to the above-mentioned solution of the utility model, the inductor L1 is an iron core coil.
[0018] The utility model according to the above scheme has the following beneficial effects:
[0019] In the above-mentioned bidirectional DC converter circuit, the input end of the input capacitor C1 is used to connect to the charging pile, and the output end of the output capacitor C2 is used to connect to the car battery. When the voltage of the input capacitor C1 is greater than the voltage of the output capacitor C2, the switch is closed, and the voltage on the output capacitor C2 drives the switch tube Q2 to work, thereby charging the input capacitor C1, thereby reducing the voltage of the car battery, which is convenient for the subsequent charging pile to charge electric vehicles exported abroad. The circuit of the utility model is relatively simple, which reduces the production cost, while taking into account the bidirectional function and simple control. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 A circuit diagram of the utility model;
[0021] Figure 2 is a circuit diagram of a charging circuit;
[0022] Figure 3 is a circuit diagram of a step-down circuit;
[0023] Figure 4 is a circuit diagram of a first voltage divider circuit;
[0024] Figure 5 is a circuit diagram of a second voltage divider circuit;
[0025] Figure 6 This is the circuit diagram of the reference circuit. DETAILED DESCRIPTION
[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0027] like Figure 1 As shown, the utility model provides a bidirectional DC converter circuit, including a charging circuit and a step-down circuit.
[0028] like Figure 2As shown, specifically, the charging circuit includes an input capacitor C1, an inductor L1, a diode D1, an output capacitor C2, a switch tube Q1, a resistor R1, and a resistor R2. One end of the inductor L1 is connected to one end of the input capacitor C1, and the other end of the inductor L1 is respectively connected to one end of the diode D1 and one end of the switch tube Q1, and the other end of the diode D1 is connected to one end of the output capacitor C2. The other end of the switch tube Q1 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to one end of the resistor R2. The other end of the input capacitor C1, the other end of the output capacitor C2, and the other end of the resistor R2 are all grounded. In addition, the switch tube Q1 is an N-channel enhancement MOS tube, and the D pole of the switch tube Q1 is respectively connected to the other end of the inductor L1 and one end of the diode D1, and the G pole of the switch tube Q1 is connected to one end of the resistor R1, and the S pole of the switch tube Q1 is grounded. Of course, in actual design, the model of the switch tube Q1 can be designed according to actual needs. In addition, the inductor L1 is an iron core coil. Of course, in actual design, the model of the inductor L1 can be designed according to actual needs.
[0029] like Figure 3 , Figure 4 As shown, in this embodiment, the step-down circuit includes a switch RLY1-B, a first voltage divider circuit, a second voltage divider circuit, and a reference circuit. One end of the switch RLY1-B is connected to the other end of the diode D1 and one end of the output capacitor C2 respectively. The first voltage divider circuit includes a resistor R4, a resistor R5, and a resistor R6. One end of the resistor R4 is connected to the other end of the switch RLY1-B, the other end of the resistor R4 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to one end of the resistor R6, and the other end of the resistor R6 is connected to the input end of the reference circuit. In addition, the switch RLY1-B is a relay. Of course, in actual design, the model of the switch RLY1-B can be designed according to actual needs.
[0030] like Figure 5 As shown, in this embodiment, the second voltage divider circuit includes resistors R7, R8, R9, R10, R11, R12, R13, and R14. One end of the resistor R7 is connected to the other end of the switch RLY1-B, the other end of the resistor R7 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to one end of the resistor R9, the other end of the resistor R9 is connected to one end of the resistor R10, the other end of the resistor R10 is connected to one end of the resistor R11, the other end of the resistor R11 is connected to one end of the resistor R12, the other end of the resistor R12 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to one end of the resistor R14, and the other end of the resistor R14 is connected to the input end of the reference circuit.
[0031] like Figure 6As shown, in this embodiment, the reference circuit includes a switch tube Q2, a voltage-stabilizing diode Z1, and a resistor R3. The switch tube Q2 is an N-channel enhancement type MOS tube. The D pole of the switch tube Q2 is connected to the other end of the resistor R6, and the G pole of the switch tube Q2 is respectively connected to the other end of the resistor R14, the cathode of the voltage-stabilizing diode Z1, and one end of the resistor R3. The S pole of the switch tube Q2, the anode of the voltage-stabilizing diode Z1, and the other end of the resistor R3 are all connected to one end of the output capacitor C2 and one end of the inductor L1 through the diode D2.
[0032] like Figure 3 As shown, in this embodiment, the step-down circuit also includes a diode D3, a diode D4, a diode D5, a diode D6, and a diode D7. One end of the diode D3 is respectively connected to the other end of the resistor R14 and the G pole of the switch tube Q2, the other end of the diode D3 is connected to one end of the diode D4, the other end of the diode D4 is connected to one end of the diode D5, the other end of the diode D5 is connected to one end of the diode D6, the other end of the diode D6 is connected to one end of the diode D7, and the other end of the diode D7 is grounded.
[0033] In this embodiment, the input end of the input capacitor C1 is used to connect to the charging pile, and the output end of the output capacitor C2 is used to connect to the car battery. The voltage of the output capacitor C2 is higher than the voltage of the input capacitor C1. When the input end of the input capacitor C1 is disconnected from the charging pile, that is, when the forward circuit composed of the inductor L1, the switch tube Q1, and the diode D1 is not working, the control switch RLY1-B is closed, and the voltage of the output capacitor C2 on the high-voltage side drives the switch tube Q2 to work through the resistor R7, the resistor R8, the resistor R9, the resistor R10, the resistor R11, the resistor R12, the resistor R13, the resistor R14, and the voltage stabilizing diode Z1, so that the output capacitor C2 on the high-voltage side is connected to the input capacitor C1 through the resistor R4, the resistor R5, the resistor R6, the switch tube Q2, and the voltage regulator diode Z1. When the input capacitor C1 is charged and the voltage of the input capacitor C1 is charged to a value close to the sum of the voltages of the diodes D3, D4, D5, D6 and D7, the driving voltage of the switch tube Q2 is gradually reduced, and the switch tube Q2 is in an amplified state, so that the voltage of the input capacitor C1 is kept stable until the forward circuit composed of the main power inductor L1, the switch tube Q1 and the diode D1 works, and the switch RLY1-B is disconnected, so as to reduce the voltage of the car battery, and facilitate the subsequent charging pile to charge the electric vehicles exported to foreign countries. The circuit of the utility model is relatively simple, which reduces the production cost, and takes into account the bidirectional function and simple control.
[0034] When charging the car, the input end of the input capacitor C1 is connected to the charging pile, and the output end of the output capacitor C2 is connected to the car battery. The input capacitor C1, inductor L1, switch tube Q1, diode D1, and output capacitor C2 form a forward boost to achieve the conversion of power from input to output, thereby charging the car. When the boost circuit is working, the loop composed of the switch RLY1-B, switch tube Q2, resistor R4, resistor R5, resistor R6 and other devices is in a non-working state.
[0035] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to the utility model.
[0036] The above is an exemplary description of the utility model patent in conjunction with the accompanying drawings. It is obvious that the implementation of the utility model patent is not limited to the above-mentioned method. As long as various improvements are made by adopting the method concept and technical solution of the utility model patent, or the concept and technical solution of the utility model patent are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.
Claims
1. A bidirectional DC converter circuit, characterized in that: It includes a charging circuit and a step-down circuit. The charging circuit includes an input capacitor C1, an inductor L1, a diode D1, and an output capacitor C2. One end of the inductor L1 is connected to one end of the input capacitor C1, the other end of the inductor L1 is connected to one end of the diode D1, the other end of the diode D1 is connected to one end of the output capacitor C2, and the other end of the input capacitor C1 and the other end of the output capacitor C2 are both grounded. The step-down circuit includes a switch and a reference circuit. The reference circuit includes a switch tube Q2. One end of the switch is respectively connected to the other end of the diode D1 and one end of the output capacitor C2. The other end of the switch is connected to one end of the switch tube Q2. The other end of the switch tube Q2 is respectively connected to one end of the inductor L1 and one end of the input capacitor C1.
2. The bidirectional DC converter circuit according to claim 1, characterized in that: The step-down circuit also includes a first voltage divider circuit and a second voltage divider circuit. The input end of the first voltage divider circuit and the input end of the second voltage divider circuit are both connected to the other end of the switch, and the output end of the first voltage divider circuit and the output end of the second voltage divider circuit are both connected to one end of the switch tube Q2.
3. The bidirectional DC converter circuit according to claim 2, characterized in that: The switch tube Q2 is a MOS tube, the D pole of the switch tube Q2 is connected to the output end of the first voltage divider circuit, the G pole of the switch tube Q2 is connected to the output end of the second voltage divider circuit, and the S pole of the switch tube Q2 is respectively connected to one end of the inductor L1 and one end of the input capacitor C1.
4. The bidirectional DC converter circuit according to claim 2, characterized in that: The reference circuit also includes a voltage-stabilizing diode Z1 and a resistor R3. The cathode of the voltage-stabilizing diode Z1 and one end of the resistor R3 are connected to the D pole of the switch tube Q2. The anode of the voltage-stabilizing diode Z1, the other end of the resistor R3, and the S pole of the switch tube Q2 are respectively connected to one end of the input capacitor C1 and one end of the inductor L1.
5. The bidirectional DC converter circuit according to claim 2, characterized in that: The switch tube Q2 is an N-channel enhancement type MOS tube.
6. The bidirectional DC converter circuit according to claim 1, characterized in that: The charging circuit also includes a switch tube Q1, a resistor R1, and a resistor R2. One end of the switch tube Q1 is respectively connected to the other end of the inductor L1 and one end of the diode D1, the other end of the switch tube Q1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the resistor R2, and the other end of the resistor R2 is grounded.
7. The bidirectional DC converter circuit according to claim 6, characterized in that: The switch tube Q1 is a MOS tube, the D pole of the switch tube Q1 is connected to the other end of the inductor L1 and one end of the diode D1 respectively, the G pole of the switch tube Q1 is connected to one end of the resistor R1, and the S pole of the switch tube Q1 is grounded.
8. The bidirectional DC converter circuit according to claim 6, characterized in that: The switch tube Q1 is an N-channel enhancement type MOS tube.
9. The bidirectional DC converter circuit according to claim 1, characterized in that: The switch is a relay.
10. The bidirectional DC converter circuit according to claim 1, characterized in that: The inductor L1 is an iron core coil.