A battery charging and discharging circuit and charging and discharging control method based on synchronous rectification control.

Abstract

This invention provides a battery charging and discharging circuit and a charging and discharging control method based on synchronous rectification control. The battery charging and discharging circuit includes a bidirectional switching power supply, a first switching module, a second switching module, an energy storage module, a control module, and a drive module. The positive terminal of the bidirectional switching power supply is connected to one end of the first switching module. The other end of the first switching module is connected to one end of the second switching module and one end of the energy storage module. The other end of the energy storage module is connected to the positive terminal of the battery. The other ends of the second switching module and the energy storage module are connected to the negative terminal of the battery. The first drive terminal of the drive module is connected to the control terminal of the first switching module, and the second control terminal of the drive module is connected to the control terminal of the second switching module. The control module drives either the first or second switching module to selectively conduct through the drive module. This invention can improve energy utilization and achieve greater energy efficiency.

Description

Technical Field

[0001] This invention relates to the field of charging and discharging technology, and specifically to a battery charging and discharging circuit and charging and discharging control method based on synchronous rectification control. Background Technology

[0002] With the development of the battery industry, battery capacity is constantly increasing. In particular, the charging and discharging current required for power batteries and energy storage batteries during production and testing is getting larger and larger, which puts higher and higher demands on the energy efficiency of equipment.

[0003] Traditional energy-consuming battery charging and discharging equipment dissipates most of the electrical energy generated during battery discharge as heat, resulting in significant energy waste and extremely low overall energy efficiency. This fails to meet the current industry demands for energy conservation, environmental protection, and efficient energy utilization. Furthermore, because these devices lack energy feedback capabilities, excess energy generated during battery discharge cannot be recovered and reused. This one-way energy consumption mode leads to extremely low energy utilization, particularly during large-scale battery testing and long-term energy storage commissioning, significantly increasing operating costs and hindering the energy-efficient and high-performance development of battery charging and discharging equipment. Summary of the Invention

[0004] To address the problems in the prior art, this invention provides a battery charging and discharging circuit and a charging and discharging control method based on synchronous rectification control.

[0005] This invention relates to a battery charging and discharging circuit based on synchronous rectification control, comprising a bidirectional switching power supply, a first switching module, a second switching module, an energy storage module, a control module, and a drive module. The positive terminal of the bidirectional switching power supply is connected to one end of the first switching module. The other end of the first switching module is connected to one end of both the second switching module and the energy storage module. The other end of the energy storage module is connected to the positive terminal of the battery. The other ends of the second switching module and the energy storage module are connected to the negative terminal of the battery. The first drive terminal of the drive module is connected to the control terminal of the first switching module, and the second control terminal of the drive module is connected to the control terminal of the second switching module. The control module drives either the first or second switching module to selectively conduct, forming a charging or discharging circuit to achieve battery charging and discharging.

[0006] Furthermore, it also includes a current detection module and a voltage detection module for detecting battery current and voltage. The output terminals of the current detection module and the voltage detection module are connected to the input terminal of the control module. The control module outputs a PWM signal to regulate the voltage and current of the charging and discharging circuit based on the detected voltage and current signals.

[0007] Furthermore, the current detection module includes a current detection element and a current isolation amplifier circuit. The input terminal of the current detection element is connected between the energy storage module and the positive terminal of the battery, and the output terminal is connected to the input terminal of the current isolation amplifier circuit. The output terminal of the current isolation amplifier circuit is connected to the input terminal of the control module.

[0008] Furthermore, the current sensing element includes a shunt resistor or a current sensor.

[0009] Furthermore, the voltage detection module includes a voltage isolation amplifier circuit, the input terminal of which is connected to the battery, and the output terminal of which is connected to the input terminal of the control module.

[0010] Furthermore, the energy storage module is an inductor connected in series with the positive terminal line.

[0011] Furthermore, it also includes a filter module disposed at the power input and output terminals of the battery.

[0012] This invention also provides a charging and discharging control method, implemented based on the aforementioned battery charging and discharging circuit based on synchronous rectification control. The charging and discharging control method includes a charging step and a discharging step, wherein... During the charging process, current flows from the bidirectional switching power supply to the battery. The first switching module acts as the main switch, and the drive module controls the first switching module to turn on while the second switching module turns off. Current flows from the positive terminal of the bidirectional switching power supply through the battery to the negative terminal of the bidirectional switching power supply. At the same time, the energy storage module stores energy. When charging is complete, the drive module controls the first switching module to turn off and the second switching module to turn on for freewheeling. The energy storage module releases energy to maintain the positive current direction, thus forming a positive charging state for the battery. During the discharge step, the second switch module acts as the main switch, and the drive module controls the second switch module to turn on while the first switch module turns off. Current flows from the positive terminal of the battery to the negative terminal, and the energy storage module stores energy simultaneously. When the discharge ends, the drive module controls the second switch module to turn off, the first switch module turns on to continue the current flow, the energy storage module releases energy, and the current flows to the bidirectional switching power supply, maintaining the current direction and providing power to the bidirectional switching power supply, thus forming a state where the battery discharges in reverse to the bidirectional switching power supply.

[0013] Compared with existing technologies, the advantages of this invention are as follows: By setting up a first switching module, a second switching module, and an energy storage module that cooperate with each other, the first or second switching module is fully turned on during battery charging and discharging. Its internal resistance is only a few milliohms, resulting in very low heat generation throughout the system, eliminating the need for a separate heat dissipation structure and reducing production costs. Furthermore, during battery discharging, the discharge energy from the energy storage module and the battery can be inverted into the AC power grid by a bidirectional switching power supply, achieving high efficiency and energy saving in the battery charging and discharging process. Attached Figure Description

[0014] To more clearly illustrate the solutions in this invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0015] Figure 1 This is a structural block diagram of the present invention; Figure 2 This is a circuit schematic diagram of an embodiment of the present invention; Figure 3 This is a schematic diagram of the charging process of the present invention; Figure 4 This is a schematic diagram of the discharge process of the present invention. Detailed Implementation

[0016] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings are used to distinguish different objects, not to describe a particular order.

[0017] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment to other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0019] like Figure 1As shown, the present invention relates to a battery charging and discharging circuit based on synchronous rectification control, comprising a bidirectional switching power supply, a first switching module, a second switching module, an energy storage module, a control module, and a drive module. The positive terminal of the bidirectional switching power supply is connected to one end of the first switching module, and the other end of the first switching module is connected to one end of the second switching module and one end of the energy storage module. The other end of the energy storage module is connected to the positive terminal of the battery, and the other ends of the second switching module and the energy storage module are connected to the negative terminal of the battery. The first drive terminal of the drive module is connected to the control terminal of the first switching module, and the second control terminal of the drive module is connected to the control terminal of the second switching module. The control module drives either the first or second switching module to selectively conduct, forming a charging or discharging circuit to realize the charging and discharging of the battery.

[0020] The first and second switching modules can be electronic switches, MOSFETs, bidirectional thyristors, etc. In this example, the energy storage module is an inductor, but it can also be an energy storage capacitor or other components.

[0021] This invention, by setting up a first switching module, a second switching module, and an energy storage module that cooperate with each other, ensures that either the first or second switching module is fully conductive during battery charging and discharging. Its internal resistance is only a few milliohms, resulting in minimal heat generation for the entire system, eliminating the need for a separate heat dissipation structure and reducing production costs. Furthermore, during battery discharging, the energy discharged by the energy storage module and the battery can be inverted into the AC power grid by a bidirectional switching power supply, achieving high efficiency and energy saving in the battery charging and discharging process.

[0022] like Figure 2 As shown, in a preferred embodiment of the present invention, this example further includes a current detection module and a voltage detection module for detecting battery current and voltage, wherein the output terminals of the current detection module and the voltage detection module are connected to the input terminal of the control module.

[0023] In this example, the current detection module includes a current sensing element and a current isolation amplifier circuit. The input terminal of the current sensing element is connected between the energy storage module and the positive terminal of the battery, and its output terminal is connected to the input terminal of the current isolation amplifier circuit. The output terminal of the current isolation amplifier circuit is connected to the input terminal of the control module. In this example, the current sensing element is a current sensor. The voltage detection module includes a voltage isolation amplifier circuit, the input terminal of which is connected to the battery, and its output terminal is connected to the input terminal of the control module.

[0024] Of course, the current detection element can also be a sampling resistor, as long as it can realize the current detection function. In this example, the voltage detection module can also use a voltage divider resistor.

[0025] Preferably, the present invention further includes a filter module disposed at the power input and output terminals of the battery. In this example, the filter module is a filter capacitor. The filter module may also employ components such as a π-type filter or an LC filter.

[0026] In this example, the first switching module is MOSFET Q1, the second switching module is MOSFET Q2, and the energy storage module is an inductor. MOSFETs Q1 and Q2, the inductor, and the filter capacitor form a bidirectional synchronous rectification circuit. Energy is stored in the inductor by switching either MOSFET Q1 or Q2 on or off, providing the rectified current to the battery load. A current sensor, current isolation amplifier circuit, and voltage isolation amplifier circuit transmit the collected current and voltage sampling signals to the control module. The control module compares and adjusts the collected signals with the set signals, outputs a PWM signal, and controls the drive module to output a drive signal, adjusting the duty cycle of the two MOSFETs to regulate the output current and voltage.

[0027] The working principle of the charging and discharging process in this example is as follows: like Figure 3 As shown, during the charging process, current flows from the bidirectional switching power supply to the battery. MOSFET Q1 acts as the main switch. When MOSFET Q1 is turned on, MOSFET Q2 is turned off, and current flows from the positive terminal of the bidirectional switching power supply through the battery to the negative terminal of the bidirectional switching power supply. At the same time, energy is stored in the inductor. When MOSFET Q1 is turned off, MOSFET Q2 is turned on for freewheeling, and the inductor releases energy, continuing to maintain the positive current direction, thus forming a positive charging state for the battery.

[0028] like Figure 4 As shown, during the discharge process, the current direction is opposite to the battery charging direction. MOSFET Q2 acts as the main switch. When MOSFET Q2 is turned on, MOSFET Q1 is turned off, and the current flows from the positive terminal of the battery to the negative terminal, while energy is stored in the inductor. When MOSFET Q2 is turned off, MOSFET Q1 is turned on for freewheeling, and the inductor releases energy. Because the bidirectional switching power supply is bidirectional, the current direction can be maintained, forming a state where the battery discharges in reverse to the bidirectional switching power supply.

[0029] In this invention, during the battery charging and discharging process, the two MOSFETs in the system operate in a switching state. In this state, the MOSFETs are fully turned on, and their internal resistance is only a few milliohms. Therefore, the heat generated by the entire system is very small. In addition, during the battery discharging process, the battery's discharge energy can be inverted to the AC power grid by a bidirectional switching power supply, which can simultaneously provide power to other devices on the same power grid, thus achieving high efficiency and energy saving in the battery charging and discharging process.

[0030] The specific embodiments described above are preferred embodiments of the present invention and are not intended to limit the specific scope of the present invention. The scope of the present invention includes, but is not limited to, these specific embodiments. All equivalent changes made in accordance with the present invention are within the protection scope of the present invention.

Claims

1. A battery charging and discharging circuit based on synchronous rectification control, characterized in that: The device includes a bidirectional switching power supply, a first switching module, a second switching module, an energy storage module, a control module, and a drive module. The positive terminal of the bidirectional switching power supply is connected to one end of the first switching module. The other end of the first switching module is connected to one end of both the second switching module and the energy storage module. The other end of the energy storage module is connected to the positive terminal of the battery. The other ends of the second switching module and the energy storage module are connected to the negative terminal of the battery. The first drive terminal of the drive module is connected to the control terminal of the first switching module, and the second control terminal of the drive module is connected to the control terminal of the second switching module. The control module drives either the first or second switching module to selectively conduct, forming a charging or discharging circuit to achieve battery charging and discharging.

2. The battery charging and discharging circuit based on synchronous rectification control according to claim 1, characterized in that: It also includes a current detection module and a voltage detection module for detecting battery current and voltage. The output terminals of the current detection module and the voltage detection module are connected to the input terminal of the control module. The control module outputs a PWM signal to regulate the voltage and current of the charging and discharging circuit based on the detected voltage and current signals.

3. The battery charging and discharging circuit based on synchronous rectification control according to claim 2, characterized in that: The current detection module includes a current detection element and a current isolation amplifier circuit. The input terminal of the current detection element is connected between the energy storage module and the positive terminal of the battery, and the output terminal is connected to the input terminal of the current isolation amplifier circuit. The output terminal of the current isolation amplifier circuit is connected to the input terminal of the control module.

4. The battery charging and discharging circuit based on synchronous rectification control according to claim 3, characterized in that: The current sensing element includes a shunt resistor or a current sensor.

5. The battery charging and discharging circuit based on synchronous rectification control according to claim 2, characterized in that: The voltage detection module includes a voltage isolation amplifier circuit, the input of which is connected to the battery, and the output of which is connected to the input of the control module.

6. The battery charging and discharging circuit based on synchronous rectification control according to any one of claims 1-5, characterized in that: The energy storage module is an inductor connected in series with the positive terminal line.

7. The battery charging and discharging circuit based on synchronous rectification control according to any one of claims 1-5, characterized in that: It also includes a filter module disposed at the power input and output terminals of the battery.

8. A charging and discharging control method, implemented based on the battery charging and discharging circuit based on synchronous rectification control as described in any one of claims 1-7, characterized in that: The charge / discharge control method includes a charging step and a discharging step, wherein... During the charging process, current flows from the bidirectional switching power supply to the battery. The first switching module acts as the main switch, and the drive module controls the first switching module to turn on while the second switching module turns off. Current flows from the positive terminal of the bidirectional switching power supply through the battery to the negative terminal of the bidirectional switching power supply. At the same time, the energy storage module stores energy. When charging is complete, the drive module controls the first switching module to turn off and the second switching module to turn on for freewheeling. The energy storage module releases energy to maintain the positive current direction, thus forming a positive charging state for the battery. During the discharge step, the second switch module acts as the main switch, and the drive module controls the second switch module to turn on while the first switch module turns off. Current flows from the positive terminal of the battery to the negative terminal, and the energy storage module stores energy simultaneously. When the discharge ends, the drive module controls the second switch module to turn off, the first switch module turns on to continue the current flow, the energy storage module releases energy, and the current flows to the bidirectional switching power supply, maintaining the current direction and providing power to the bidirectional switching power supply, thus forming a state where the battery discharges in reverse to the bidirectional switching power supply.

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