Push-pull circuit and energy storage power supply

Abstract

The utility model relates to the technical field of energy storage power supplies, and mainly provides a push-pull circuit and an energy storage power supply, the push-pull circuit comprises a voltage regulation module, a current limiting module and a sampling control module which are respectively connected with the voltage regulation module, and a bus capacitor; the current limiting module and the sampling control module are also connected with the bus capacitor. The voltage adjusting module is used for receiving and adjusting power supply voltage to obtain charging voltage and inputting the charging voltage to the current limiting module and the sampling control module; when the current limiting module receives the charging voltage, the current limiting module outputs the corresponding charging current to the bus capacitor based on the charging voltage so as to avoid the impact of large current on the bus capacitor. In the charging process of the bus capacitor, the difference value between the bus voltage and the charging voltage becomes lower and lower, and when the bus voltage is larger than the preset voltage, the sampling control module starts to work and controls the current limiting module to stop working, so that the voltage adjusting module charges the bus capacitor based on the sampling control module; and the loss in the circuit is further reduced.

Description

[Technical Field]

[0001] This utility model relates to the technical field of energy storage power supplies, and in particular to a push-pull circuit and an energy storage power supply. [Background Technology]

[0002] Push-pull circuits, as a common power conversion circuit, are widely used in switching power supplies, audio power amplification, and many other applications. However, push-pull circuits present several challenging problems during actual operation. When the MOSFET is turned on, the initial voltage of the downstream capacitor is zero, effectively creating a short circuit. This causes the primary current to increase rapidly within a very short time. Excessive current not only causes a momentary thermal shock to the MOSFET, accelerating its aging, but in severe cases, it can even burn out the MOSFET, rendering the entire circuit malfunction and significantly reducing its reliability and stability. Conversely, when the MOSFET is turned off, the leakage inductance of the transformer, according to the formula V = L * Δi / Δt, generates a high voltage spike. This necessitates the selection of a MOSFET with high voltage withstand capability to withstand this voltage spike. However, high-voltage MOSFETs are often more expensive and have relatively higher on-resistance, increasing circuit cost and leading to increased conduction losses, thus reducing overall circuit efficiency. [Utility Model Content]

[0003] This utility model provides a push-pull circuit and an energy storage power supply, aiming to solve the technical problems of large current surges when the MOSFET is turned on and high voltage spikes when it is turned off in the prior art.

[0004] To solve the above-mentioned technical problems, one technical solution adopted by this utility model is: to provide a push-pull circuit, which includes a voltage adjustment module, a current limiting module, a sampling control module, and a bus capacitor;

[0005] The voltage adjustment module is connected to the current limiting module and the sampling control module respectively, and the current limiting module and the sampling control module are also connected to the bus capacitor;

[0006] The voltage adjustment module is used to receive and adjust the power supply voltage to obtain the charging voltage, and input the charging voltage to the current limiting module and the sampling control module;

[0007] The current limiting module responds to the charging voltage and outputs a corresponding charging current to the bus capacitor based on the magnitude of the charging voltage, so as to charge the bus capacitor.

[0008] The sampling control module is used to collect the bus voltage on the bus capacitor, start working when the bus voltage is greater than a preset voltage, and control the current limiting module to stop working, so that the voltage adjustment module charges the bus capacitor based on the sampling control module.

[0009] Optionally, the current limiting module includes a current limiting resistor;

[0010] The current-limiting resistor is connected to the voltage adjustment module and the bus capacitor, respectively.

[0011] Optionally, the current limiting module further includes a constant current unit;

[0012] The constant current unit is connected to the current limiting resistor, the voltage adjustment module, and the bus capacitor, respectively;

[0013] The constant current unit is used to receive the charging voltage and, when the charging voltage is greater than the reference voltage, input the charging voltage to the current limiting resistor to limit the charging current based on the current limiting resistor.

[0014] Optionally, the constant current unit includes a switching transistor Q7, a resistor R8, and a Zener diode ZD1;

[0015] The first terminal of the switching transistor Q7 is connected to the voltage adjustment module, the second terminal of the switching transistor Q7 is connected to the bus capacitor through the current limiting resistor, the control terminal of the switching transistor Q7 is connected to the voltage adjustment module through the resistor R8, the control terminal of the switching transistor Q7 is also connected to the cathode of the Zener diode ZD1, and the anode of the Zener diode ZD1 is connected to the bus capacitor.

[0016] Optionally, the sampling control module includes a relay RLY1 and a first control unit;

[0017] The connection terminals of the relay RLY1 are respectively connected to the voltage adjustment module and the bus capacitor, and the coil terminal of the relay RLY1 is connected to the first control unit. The first control unit is also connected to the bus capacitor.

[0018] The first control unit is used to collect the bus voltage on the bus capacitor, and when the bus voltage is greater than a preset voltage, control the coil terminal of the relay RLY1 to be energized, thereby controlling the relay RLY1 to charge the bus capacitor.

[0019] Optionally, the first control unit includes a switch Q5, a resistor R4, and a resistor R5;

[0020] The control terminal of the switch Q5 is connected to the bus capacitor through the resistor R4, the second terminal of the switch Q5 is grounded through the resistor R5, the first terminal of the switch Q5 is connected to the coil terminal of the relay RLY1, and the second terminal of the switch Q5 is used for grounding.

[0021] Optionally, the sampling control module includes a second control unit and a switching unit;

[0022] The second control unit is connected to the bus capacitor and the switching unit respectively, and the switching unit is connected to the voltage adjustment module and the bus capacitor respectively;

[0023] The second control unit is used to collect the bus voltage on the bus capacitor, and control the switching unit to start working when the bus voltage is greater than a preset voltage, so as to charge the bus capacitor based on the switching unit.

[0024] Optionally, the second control unit includes a switch Q6, an optocoupler U1, a resistor R2, a resistor R6, and a resistor R7;

[0025] The control terminal of the switch Q6 is connected to the bus capacitor through the resistor R6. The second terminal of the switch Q6 is grounded through the resistor R7. The first terminal of the switch Q6 is connected to the second pin of the optocoupler U1. The second terminal of the switch Q6 is used for grounding. The first pin of the optocoupler U1 is connected to the first power supply through the resistor R2. The fourth pin of the optocoupler U1 is connected to the second power supply. The third pin of the optocoupler U1 is connected to the switching unit.

[0026] Optionally, the switching unit includes a switching transistor Q3, a switching transistor Q4, a resistor R1, and a resistor R3;

[0027] The control terminal of the switch Q3 is connected to the control terminals of resistor R3 and switch Q4 respectively. Resistor R3 is also connected to the third pin of optocoupler U1. The first terminal of switch Q3 is connected to the voltage adjustment module. The second terminal of switch Q3 is connected to the second terminal of switch Q4. The second terminal of switch Q3 is also connected to resistor R3 through resistor R1. The first terminal of switch Q4 is connected to the bus capacitor.

[0028] To solve the above-mentioned technical problems, another technical solution adopted in this utility model embodiment is: to provide an energy storage power source, the energy storage power source comprising:

[0029] Controller; and

[0030] The push-pull circuit described above.

[0031] Unlike related technologies, this utility model provides a push-pull circuit and energy storage power supply. The push-pull circuit includes a voltage adjustment module, a current limiting module, a sampling control module, and a bus capacitor. The voltage adjustment module is connected to both the current limiting module and the sampling control module, which are also connected to the bus capacitor. The voltage adjustment module receives and adjusts the power supply voltage to obtain a charging voltage, and inputs this charging voltage to the current limiting module and the sampling control module. When the current limiting module receives the charging voltage, it outputs a corresponding charging current to the bus capacitor based on the magnitude of the charging voltage, thereby preventing large currents from impacting the bus capacitor. As the bus capacitor charges, the difference between the bus voltage and the charging voltage decreases. When the bus voltage exceeds a preset voltage, the sampling control module starts working and controls the current limiting module to stop working. This allows the voltage adjustment module to charge the bus capacitor based on the sampling control module, thereby reducing circuit losses. [Attached Image Description]

[0032] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0033] Figure 1 This is a structural block diagram of an energy storage power supply provided in an embodiment of this utility model;

[0034] Figure 2 This is a structural block diagram of a push-pull circuit provided in an embodiment of the present invention;

[0035] Figure 3 This is a circuit diagram of a push-pull circuit provided in an embodiment of this utility model;

[0036] Figures 4a-4b This is a structural block diagram of a push-pull circuit provided in another embodiment of the present invention;

[0037] Figures 5a-5b A circuit diagram of a current limiting module provided for an embodiment of this utility model;

[0038] Figure 6a A circuit diagram of a sampling control module provided for an embodiment of this utility model;

[0039] Figure 6b A circuit diagram of a sampling control module provided in another embodiment of this utility model.

Detailed Implementation Methods

[0040] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0041] The technical features involved in the various embodiments of this application described below do not conflict with each other and can be combined with each other.

[0042] When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements between them.

[0043] The terms "first," "second," etc., used in the specification and claims of this utility model are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, the first object can be one or more.

[0044] Unless otherwise defined, all technical and scientific terms used in this specification 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 scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0045] Please see Figure 1 , Figure 1 This is a structural block diagram of an energy storage power supply provided in an embodiment of this utility model, as shown below. Figure 1 As shown, the energy storage power supply 100 includes a controller 10 and a push-pull circuit 20. The push-pull circuit 20 is connected to the controller 10 and is used to receive drive signals output by the controller 10 and start working according to the drive signals. In another embodiment, as... Figure 1 As shown, the energy storage power supply 100 also includes a power supply 30; the power supply 30 is connected to the push-pull circuit 20. The push-pull circuit 20 is also used to receive the power supply voltage output by the power supply 30, and to process the power supply voltage after starting to work according to the drive signal, thereby outputting a target voltage. The power supply 30 can be a photovoltaic input source, a battery, or other power supply device.

[0046] In another embodiment, please refer to Figure 2 , Figure 2This is a structural block diagram of a push-pull circuit provided in an embodiment of the present invention, as shown below. Figure 2 As shown, the push-pull circuit 20 includes a voltage adjustment module 21, a current limiting module 22, a sampling control module 23, and a bus capacitor EC1; the voltage adjustment module 21 is connected to the current limiting module 22 and the sampling control module 23 respectively, and the current limiting module 22 and the sampling control module 23 are also connected to the bus capacitor EC1.

[0047] The voltage adjustment module 21 is used to receive and adjust the power supply voltage to obtain the charging voltage, and input the charging voltage to the current limiting module 22 and the sampling control module 23;

[0048] The current limiting module 22 responds to the charging voltage and outputs a corresponding charging current to the bus capacitor EC1 based on the magnitude of the charging voltage, so as to charge the bus capacitor EC1.

[0049] The sampling control module 23 is used to collect the bus voltage on the bus capacitor EC1, so as to start working when the bus voltage is greater than a preset voltage, and control the current limiting module 22 to stop working, so that the voltage adjustment module 21 charges the bus capacitor EC1 based on the sampling control module 23.

[0050] The voltage adjustment module 21 is also connected to the power supply 30 and the controller 10. When the voltage adjustment module 21 receives a drive signal from the controller 10, it processes the power supply voltage of the power supply 30 according to the drive signal and inputs the processed voltage to the bus capacitor EC1, thereby charging the bus capacitor EC1. It should be noted that when the voltage adjustment module 21 operates according to the drive signal, the bus voltage of the bus capacitor EC1 is zero, resulting in a very large primary current in the push-pull circuit 20, which could potentially damage the voltage adjustment module 21. Therefore, by introducing the current limiting module 22, when the voltage adjustment module 21 outputs a charging voltage based on the drive signal and the power supply voltage, the current limiting module 22 responds to the charging voltage and suppresses the charging current input to the bus capacitor EC1 based on the magnitude of the charging voltage, thereby preventing damage to the circuit components from the primary current generated when the voltage adjustment module 21 operates, and thus improving circuit safety.

[0051] During the process of the voltage adjustment module 21 charging the bus capacitor EC1 based on the current limiting module 22, the sampling control module 23 will collect the bus voltage of the bus capacitor EC1 in real time, and start working when the bus voltage is greater than the preset voltage, and control the current limiting module 22 to stop working, so that the voltage adjustment module 21 charges the bus capacitor EC1 based on the sampling control module 23, thereby reducing circuit loss.

[0052] In yet another embodiment, please refer to Figure 3 , Figure 3 This is a circuit diagram of a push-pull circuit provided in an embodiment of this utility model, such as... Figure 3 As shown, the voltage adjustment module 21 includes switching transistors Q1 and Q2, and a transformer T1. Switches Q1 and Q2 are both connected to the transformer T1, which is connected to both the current limiting module 22 and the sampling control module 23. The transformer T1 also receives the power supply voltage from the power supply 30. When the push-pull circuit 20 needs to operate, the controller 10 outputs a drive signal to switches Q1 and Q2 to control their cyclic operation. After switch Q1 or Q2 starts operating, the transformer T1 outputs a charging voltage to the current limiting module 22 and the sampling control module 23 based on the on / off status of switch Q1 or Q2 and the power supply voltage.

[0053] In another embodiment, the push-pull circuit 20 further includes a bridge module, such as... Figure 3 As shown, the bridge module includes diodes D1, D2, D3, and D4. The bridge module is used to receive the charging voltage output by the current limiting module 22 or the sampling control module 23, process the charging voltage, and finally input the processed charging voltage to the bus capacitor EC1 to charge the bus capacitor EC1.

[0054] In another embodiment, please refer to Figures 4a-4b , Figures 4a-4b This is a structural block diagram of a push-pull circuit provided in another embodiment of the present invention, as shown below. Figures 4a-4bAs shown, the current limiting module 22 includes a current limiting resistor RT, which is connected to both the voltage adjustment module 21 and the bus capacitor EC1. When the voltage adjustment module 21 outputs a charging voltage to the current limiting module 22, the current limiting resistor RT consumes the charging voltage, thus preventing a large voltage from being directly input to the bus capacitor EC1. It should be noted that when the resistance of the current limiting resistor RT is constant, since the voltage across a resistor is inversely proportional to the current, the larger the charging voltage output by the voltage adjustment module 21, the smaller the charging current output by the current limiting resistor RT will be. Based on this, the primary current in the circuit can be limited according to the magnitude of the charging voltage, thereby avoiding the impact of large currents on the circuit.

[0055] In some embodiments, when selecting the current-limiting resistor RT, it is necessary to ensure that the current-limiting resistor RT can effectively limit the primary current in the circuit at the instant the push-pull circuit 20 is operating, thereby preventing the generation of large currents that could damage the circuit components. The current-limiting resistor RT can be a resistor with a fixed resistance value, or it can be a thermistor or an adjustable resistor, etc. For example, when the current-limiting resistor RT is a thermistor with a positive temperature coefficient, the larger the charging voltage, the larger the resistance value of the thermistor, thereby effectively limiting the charging current.

[0056] In yet another embodiment, such as Figures 4a-4b As shown, the current limiting module 22 further includes a constant current unit 221, which is connected to the current limiting resistor RT, the voltage adjustment module 21 and the bus capacitor EC1 respectively.

[0057] The constant current unit 221 is used to receive the charging voltage and, when the charging voltage is greater than the reference voltage, input the charging voltage to the current limiting resistor RT to limit the charging current based on the current limiting resistor RT.

[0058] It should be noted that the reference voltage is determined based on the maximum voltage of the current-limiting resistor RT. When the voltage adjustment module 21 outputs the charging voltage, the constant current unit 221 ensures that the charging voltage input to the current-limiting resistor RT is greater than the reference voltage, and the current of the push-pull circuit 20 is limited by the current-limiting resistor RT, thereby keeping the charging current input to the bus capacitor EC1 constant. Based on this, the charging current can be prevented from changing with the charging voltage, thus improving the stability of the push-pull circuit 20.

[0059] For further details, please refer to Figures 5a-5b , Figures 5a-5b A circuit diagram of a current limiting module provided for embodiments of this utility model; in some embodiments, such as... Figure 5aAs shown, the constant current unit 221 includes a switching transistor Q7, a resistor R8, and a Zener diode ZD1. The first terminal of the switching transistor Q7 is connected to the voltage adjustment module 21, the second terminal of the switching transistor Q7 is connected to the bus capacitor EC1 through the current limiting resistor RT, the control terminal of the switching transistor Q7 is connected to the voltage adjustment module 21 through the resistor R8, the control terminal of the switching transistor Q7 is also connected to the cathode of the Zener diode ZD1, and the anode of the Zener diode ZD1 is connected to the bus capacitor EC1.

[0060] When the voltage adjustment module 21 outputs the charging voltage, the charging voltage is input to the Zener diode ZD1 through the resistor R8. If the charging voltage is greater than the Zener diode ZD1's regulated voltage (reference voltage), the Zener diode ZD1 will break down, thereby turning on the switch Q7. When the switch Q7 is turned on, the charging voltage is input to the bus capacitor EC1 through the current-limiting resistor RT, thereby charging the bus capacitor EC1.

[0061] In yet another embodiment, such as Figure 5b As shown, the constant current unit 221 includes a switching transistor Q8, a resistor R9, and a Zener diode ZD2. The first terminal of the switching transistor Q8 is connected to the voltage adjustment module 21 via the current-limiting resistor RT, the second terminal of the switching transistor Q8 is connected to the bus capacitor EC1, the control terminal of the switching transistor Q8 is connected to the anode of the Zener diode ZD2, and the cathode of the Zener diode ZD2 is connected to the voltage adjustment module 21. The control terminal of the switching transistor Q8 is also connected to the bus capacitor EC1 via the resistor R9. When the charging voltage is greater than the Zener voltage of the Zener diode ZD2, the switching transistor Q8 is turned on, and the current-limiting resistor RT begins charging the bus capacitor EC1 based on the charging voltage. Therefore, the voltage input to the constant current unit 221 can be made greater than the reference voltage by the Zener diode ZD2, thereby enabling constant current charging of the bus capacitor EC1.

[0062] In another embodiment, such as Figure 4a As shown, the sampling control module 23 includes a relay RLY1 and a first control unit 231;

[0063] The connection terminals of the relay RLY1 are respectively connected to the voltage adjustment module 21 and the bus capacitor EC1, and the coil terminal of the relay RLY1 is connected to the first control unit 231. The first control unit 231 is also connected to the bus capacitor EC1.

[0064] The first control unit 231 is used to collect the bus voltage on the bus capacitor EC1, and when the bus voltage is greater than a preset voltage, control the coil terminal of the relay RLY1 to be energized, thereby controlling the relay RLY1 to charge the bus capacitor EC1.

[0065] Specifically, when the voltage adjustment module 21 charges the bus capacitor EC1 through the current limiting module 22, the first control unit 231 collects the bus voltage of the bus capacitor EC1 in real time and starts working when the bus voltage is greater than a preset voltage, thereby controlling the coil terminal of the relay RLY1 to be energized. When the coil terminal of the relay RLY1 is energized, the connection terminal of the relay RLY1 is closed, thereby controlling the current limiting module 22 to stop working, so that the charging voltage output by the voltage adjustment module 21 is input to the bus capacitor EC1 through the relay RLY1 to charge the bus capacitor EC1.

[0066] In some implementation examples, please refer to Figure 6a , Figure 6a A circuit diagram of a sampling control module provided for an embodiment of this utility model, as shown below. Figure 6a As shown, the first control unit 231 includes a switch Q5, a resistor R4, and a resistor R5; the control terminal of the switch Q5 is connected to the bus capacitor EC1 through the resistor R4, the second terminal of the switch Q5 is grounded through the resistor R5, the first terminal of the switch Q5 is connected to the coil terminal of the relay RLY1, and the second terminal of the switch Q5 is used for grounding.

[0067] During the charging process of the bus capacitor EC1 by the voltage adjustment module 21 through the current-limiting resistor RT, the switching transistor Q5 also receives the bus voltage on the bus capacitor EC1 in real time through the resistor R4. When the voltage after the voltage division by the resistors R4 and R5 is greater than the turn-on voltage of the switching transistor Q5 (i.e., the bus voltage is greater than the preset voltage), the switching transistor Q5 turns on, thereby pulling down the voltage at pin 1 of the relay RLY1. After the voltage at pin 1 of the relay RLY1 is pulled down, current flows through the coil of the relay RLY1, thereby causing the relay RLY1 to close. At this time, the current-limiting resistor RT is short-circuited, and the charging voltage is input to the bus capacitor EC1 through the relay RLY1, thereby charging the bus capacitor EC1.

[0068] In yet another embodiment, such as Figure 4b As shown, the sampling control module 23 includes a second control unit 232 and a switching unit 233;

[0069] The second control unit 232 is connected to the bus capacitor EC1 and the switching unit 233 respectively, and the switching unit 233 is connected to the voltage adjustment module 21 and the bus capacitor EC1 respectively;

[0070] The second control unit 232 is used to collect the bus voltage on the bus capacitor EC1, and control the switching unit 233 to start working when the bus voltage is greater than a preset voltage, so as to charge the bus capacitor EC1 based on the switching unit 233.

[0071] Specifically, when the voltage adjustment module 21 charges the bus capacitor EC1 through the current limiting module 22, the second control unit 232 collects the bus voltage on the bus capacitor EC1 in real time. When the bus voltage is greater than the preset voltage, it outputs a control signal to the switching unit 233, causing the switching unit 233 to start working based on the control signal, thereby controlling the current limiting module 22 to stop working. At this time, the charging voltage output by the voltage adjustment module 21 is input to the bus capacitor EC1 through the switching unit 233, thereby charging the bus capacitor EC1.

[0072] In yet another embodiment, please refer to Figure 6b , Figure 6b A circuit diagram of a sampling control module provided for another embodiment of this utility model is shown below. Figure 6b As shown, the second control unit 232 includes a switch Q6, an optocoupler U1, a resistor R2, a resistor R6, and a resistor R7; the switching unit 233 includes a switch Q3, a switch Q4, a resistor R1, and a resistor R3.

[0073] The control terminal of the switching transistor Q6 is connected to the bus capacitor EC1 through the resistor R6. The second terminal of the switching transistor Q6 is grounded through the resistor R7. The first terminal of the switching transistor Q6 is connected to the second pin of the optocoupler U1. The second terminal of the switching transistor Q6 is used for grounding. The first pin of the optocoupler U1 is connected to the first power supply (VCC1) through the resistor R2. The fourth pin of the optocoupler U1 is connected to the second power supply (VCC2). The third pin of the optocoupler U1 is connected to the switching unit 233.

[0074] The control terminal of the switch Q3 is connected to the control terminals of resistor R3 and switch Q4 respectively. Resistor R3 is also connected to the third pin of optocoupler U1. The first terminal of switch Q3 is connected to voltage adjustment module 21. The second terminal of switch Q3 is connected to the second terminal of switch Q4. The second terminal of switch Q3 is also connected to resistor R3 through resistor R1. The first terminal of switch Q4 is connected to bus capacitor EC1.

[0075] Specifically, when the voltage adjustment module 21 charges the bus capacitor EC1 through the current-limiting resistor RT, resistors R6 and R7 divide the bus voltage. When the divided bus voltage is greater than the turn-on voltage of the switch Q6, the switch Q6 turns on, grounding the second pin of the optocoupler U1 and enabling it to operate. Once the optocoupler U1 is operational, its third pin outputs a voltage through resistor R3 to the control terminals of switches Q3 and Q4, turning them on and short-circuiting the current-limiting resistor RT. This allows the bus capacitor EC3 to be charged via switches Q3 and Q4, reducing voltage loss and improving energy utilization. The switching transistors Q3 and Q4 together form an anti-backflow module. The body diodes of the switching transistors Q3 and Q4 can effectively prevent current backflow when the switching transistors Q3 and Q4 are disconnected.

[0076] This utility model embodiment provides a push-pull circuit, which includes a voltage adjustment module, a current limiting module, a sampling control module, and a bus capacitor. The voltage adjustment module is connected to both the current limiting module and the sampling control module, and both the current limiting module and the sampling control module are also connected to the bus capacitor. The voltage adjustment module receives and adjusts the power supply voltage to obtain a charging voltage, and inputs the charging voltage to the current limiting module and the sampling control module. When the current limiting module receives the charging voltage, it outputs a corresponding charging current to the bus capacitor based on the magnitude of the charging voltage, thereby avoiding the impact of large current on the bus capacitor. As the bus capacitor charges, the difference between the bus voltage and the charging voltage decreases. When the bus voltage exceeds a preset voltage, the sampling control module starts working and controls the current limiting module to stop working, so that the voltage adjustment module charges the bus capacitor based on the sampling control module, thereby reducing losses in the circuit.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above, which are not provided in detail for the sake of brevity; although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A push-pull circuit, characterized by The push-pull circuit comprises a voltage adjustment module, a current limiting module, a sampling control module and a bus capacitor; The voltage adjustment module is connected with the current limiting module and the sampling control module respectively, and the current limiting module and the sampling control module are also connected with the bus capacitor; The voltage adjustment module is used for receiving and adjusting a power supply voltage to obtain a charging voltage, and inputting the charging voltage to the current limiting module and the sampling control module; The current limiting module is used for outputting a corresponding charging current to the bus capacitor based on the size of the charging voltage in response to the charging voltage, so as to charge the bus capacitor; The sampling control module is used for collecting a bus voltage on the bus capacitor, and starting to work when the bus voltage is greater than a preset voltage, and controlling the current limiting module to stop working, so that the voltage adjustment module charges the bus capacitor based on the sampling control module.

2. The push-pull circuit of claim 1, wherein, The current limiting module comprises a current limiting resistor; The current limiting resistor is connected with the voltage adjustment module and the bus capacitor respectively.

3. The push-pull circuit of claim 2, wherein, The current limiting module further comprises a constant current unit; The constant current unit is connected with the current limiting resistor, the voltage adjustment module and the bus capacitor respectively; The constant current unit is used for receiving the charging voltage, and inputting the charging voltage to the current limiting resistor when the charging voltage is greater than a reference voltage, so as to limit the charging current based on the current limiting resistor.

4. The push-pull circuit of claim 3, wherein, The constant current unit comprises a switch tube Q7, a resistor R8 and a voltage stabilizing tube ZD1; The first end of the switch tube Q7 is connected with the voltage adjustment module, the second end of the switch tube Q7 is connected with the bus capacitor through the current limiting resistor, the control end of the switch tube Q7 is connected with the voltage adjustment module through the resistor R8, the control end of the switch tube Q7 is also connected with the cathode of the voltage stabilizing tube ZD1, and the anode of the voltage stabilizing tube ZD1 is connected with the bus capacitor.

5. The push-pull circuit according to any of claims 1-4, characterized in that, The sampling control module comprises a relay RLY1 and a first control unit; The connection end of the relay RLY1 is connected with the voltage adjustment module and the bus capacitor respectively, the coil end of the relay RLY1 is connected with the first control unit, and the first control unit is also connected with the bus capacitor; The first control unit is used for collecting the bus voltage on the bus capacitor, and controlling the coil end of the relay RLY1 to be electrified when the bus voltage is greater than a preset voltage, so as to control the relay RLY1 to charge the bus capacitor.

6. The push-pull circuit of claim 5, wherein, The first control unit comprises a switch tube Q5, a resistor R4 and a resistor R5; The control end of the switch tube Q5 is connected with the bus capacitor through the resistor R4, the second end of the switch tube Q5 is grounded through the resistor R5, the first end of the switch tube Q5 is connected with the coil end of the relay RLY1, and the second end of the switch tube Q5 is used for grounding.

7. The push-pull circuit according to any of claims 1-4, characterized in that The sampling control module comprises a second control unit and a switch unit; The second control unit is connected with the bus capacitor and the switch unit respectively, and the switch unit is connected with the voltage adjustment module and the bus capacitor respectively; The second control unit is used for collecting bus voltage on the bus capacitor, and controlling the switch unit to start working when the bus voltage is greater than a preset voltage, so as to charge the bus capacitor based on the switch unit.

8. The push-pull circuit of claim 7, wherein, The second control unit comprises a switch tube Q6, an optical coupler U1, a resistor R2, a resistor R6 and a resistor R7. The control end of the switch tube Q6 is connected with the bus capacitor through the resistor R6, the second end of the switch tube Q6 is grounded through the resistor R7, the first end of the switch tube Q6 is connected with the second pin of the optical coupler U1, the second end of the switch tube Q6 is used for grounding, the first pin of the optical coupler U1 is connected with a first power supply through the resistor R2, the fourth pin of the optical coupler U1 is connected with a second power supply, and the third pin of the optical coupler U1 is connected with the switch unit.

9. The push-pull circuit of claim 8, wherein, The switch unit comprises a switch tube Q3, a switch tube Q4, a resistor R1 and a resistor R3. The control end of the switch tube Q3 is connected with the resistor R3 and the control end of the switch tube Q4 respectively, the resistor R3 is also connected with the third pin of the optical coupler U1, the first end of the switch tube Q3 is connected with the voltage adjustment module, the second end of the switch tube Q3 is connected with the second end of the switch tube Q4, the second end of the switch tube Q3 is also connected with the resistor R3 through the resistor R1, and the first end of the switch tube Q4 is connected with the bus capacitor.

10. An energy storage power supply, characterized by, The energy storage power supply comprises: a controller; and The push-pull circuit according to any one of claims 1-9.

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