Pre-charging and discharging circuit and power supply system
By combining a pre-charge capacitor, a pre-charge resistor, a diode, and a discharge unit, the problem of inrush current at the moment of power-on of the power supply system is solved, achieving a low-loss and high-safety pre-charge and discharge function, simplifying the control logic, and improving the reliability and practicality of the circuit.
Patent Information
- Application Number
- CN202422836911.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-19
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-11-19
AI Technical Summary
Existing power supply systems are prone to generating large inrush currents at the moment of power-on, which can damage components. Furthermore, the pre-charging circuit control logic is complex and has high losses, and the lack of a discharge circuit poses a risk of electric shock.
The circuit design employs a combination of pre-charge capacitor, pre-charge resistor, diode, and discharge unit. Pre-charging is achieved through diode and pre-charge resistor, and the discharge unit conducts to discharge when power is off, avoiding the control logic of switching transistors and high losses.
It reduces precharge loss, improves safety and reliability, prevents electric shock risk, simplifies control logic, and enhances the practicality of the circuit.
Smart Images
Figure CN223567338U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of electronic power, in particular to a pre-charge and discharge circuit and a power supply system. BACKGROUND
[0002] With the rapid development of science and technology, more and more power supply systems or electrical systems have also been widely popularized, and these power supply systems or electronic devices often need to use energy storage devices for power supply, but at the power-on moment of these power supply systems or electronic devices, a large impact current is often generated, which may cause damage to other components.
[0003] In related technologies, relevant technical personnel generally set a corresponding pre-charge circuit in the power supply system or electronic device, and elements such as inductors and / or capacitors that can store energy can be used in the pre-charge circuit, so that at power-on, the switch tube provided on the pre-charge circuit can be first turned on to make the energy storage device pre-charge the inductor and / or capacitor, and then the switch tube is turned off after pre-charging is completed, so that the energy storage device starts to output a large current to the load. In this way, the impact current in the circuit can be reduced by pre-charging the capacitor and / or inductor.
[0004] However, this scheme needs to set an additional control circuit to control the conduction or turn-off of the switch tube provided on the pre-charge circuit, and the control logic is complex, and the switch tube has high loss when a large current flows through the pre-charge circuit. In addition, most schemes in related technologies do not set a circuit that can discharge the pre-charge capacitor, which may pose an electric shock risk. CONTENT
[0005] The purpose of the present application is to provide a pre-charge and discharge circuit and a power supply system, which can reduce pre-charge loss and improve safety, reliability and practicability.
[0006] Embodiments of the present application are implemented as follows:
[0007] In a first aspect, the present application provides a pre-charge and discharge circuit, which comprises a pre-charge capacitor, a pre-charge resistor, a diode and a discharge unit.
[0008] The anode of the diode is used to connect the anode of the energy storage element and the control end of the discharge unit, and the cathode of the diode is connected with the first end of the pre-charge resistor and the first end of the discharge unit, respectively.
[0009] The second end of the pre-charge resistor is connected with the first plate of the pre-charge capacitor, and the second plate of the pre-charge capacitor is connected with the second end of the discharge unit and the cathode of the energy storage element, respectively.
[0010] The first plate of the pre-charge capacitor is further connected to the positive pole of the energy storage element, and the second plate of the pre-charge capacitor is further connected to the negative pole of the energy storage element.
[0011] The discharge unit is configured to be turned on when the energy storage element stops outputting electric energy to the pre-charge capacitor, so that the pre-charge capacitor releases electric charge through the pre-charge resistor and the discharge unit.
[0012] Optionally, the discharge unit comprises a first switch tube.
[0013] The first pole of the first switch tube is connected to the negative pole of the diode and the first end of the pre-charge resistor, respectively, the second pole of the first switch tube is connected to the second plate of the pre-charge capacitor and the negative pole of the energy storage element, respectively, and the third pole of the first switch tube is connected to the positive pole of the energy storage element.
[0014] The first switch tube is configured to be turned on when the energy storage element stops outputting electric energy to the pre-charge capacitor, so that the pre-charge capacitor releases electric charge through the pre-charge resistor and the discharge unit.
[0015] Optionally, the discharge unit further comprises a first resistor.
[0016] The first resistor is connected between the third pole of the first switch tube and the positive pole of the energy storage element.
[0017] Optionally, the pre-charge and discharge circuit further comprises a slow start unit.
[0018] The first end of the slow start unit is connected to the positive pole of the diode and the control end of the discharge unit, respectively, the second end of the slow start unit is connected to the negative pole of the energy storage element, and the third end of the slow start unit is connected to the second plate of the pre-charge capacitor.
[0019] Optionally, the slow start unit comprises a second resistor, a third resistor, a slow start capacitor and a second switch tube.
[0020] The first end of the second resistor is connected to the positive pole of the diode and the control end of the discharge unit, respectively, the second end of the second resistor is connected to the first end of the third resistor, the first plate of the slow start capacitor and the first pole of the second switch tube, respectively, the second end of the third resistor is connected to the second plate of the slow start capacitor, the second pole of the second switch tube and the negative pole of the energy storage element, respectively.
[0021] The third pole of the second switch tube is connected to the second plate of the pre-charge capacitor.
[0022] Optionally, the slow start unit further comprises a fourth resistor.
[0023] The fourth resistor is connected between the first plate of the pre-charge capacitor and the first electrode of the second switch tube.
[0024] Optionally, the first plate of the pre-charge capacitor is further configured to connect a positive electrode of a power loop, and the second plate of the pre-charge capacitor is further configured to connect a negative electrode of the power loop, respectively.
[0025] In a second aspect, the embodiments of the present application provide a power supply system, which comprises at least a power loop and any of the pre-charge and discharge circuits according to the first aspect.
[0026] Optionally, the power loop comprises a plurality of switch tubes, a transformer, an inductor, a third capacitor and a fourth capacitor.
[0027] Optionally, the power supply system further comprises an energy storage element.
[0028] The embodiments of the present application have the following beneficial effects:
[0029] The pre-charge and discharge circuit according to the embodiments of the present application comprises a pre-charge capacitor, a pre-charge resistor, a diode and a discharge unit. Specifically, the positive electrode of the diode is connected to the positive electrode of an energy storage element and the control terminal of the discharge unit, and the negative electrode of the diode is connected to the first end of the pre-charge resistor and the first end of the discharge unit, respectively. The second end of the pre-charge resistor is connected to the first plate of the pre-charge capacitor, and the second plate of the pre-charge capacitor is connected to the second end of the discharge unit and the negative electrode of the energy storage element, respectively. The first plate of the pre-charge capacitor is further connected to the positive electrode of the energy storage element, and the second plate of the pre-charge capacitor is further connected to the negative electrode of the energy storage element.
[0030] After starting power-on, the energy storage element can directly pre-charge the pre-charge capacitor through the diode and the pre-charge resistor, without the need to set other switch devices, and thus without the need to set complex control logic. Moreover, since there is no switch device in the power transmission path between the energy storage element and the pre-charge capacitor, even if the energy storage element outputs a large current, the loss can be kept low. In addition, in the case of power-off, the discharge unit is turned on at this time, so that the pre-charge capacitor can release the electric charge through the pre-charge resistor and the discharge unit. In this way, the pre-charge capacitor can be ensured to be completely discharged or in a low charge state, and the risk of electric shock can be greatly reduced.
[0031] In addition, due to the presence of the diode, when the pre-charge capacitor is discharged through the pre-charge resistor and the discharge unit, the current flowing through the pre-charge resistor can be prevented from directly flowing into the control terminal of the discharge unit, and thus the problem of causing the discharge unit to be turned off again and the pre-charge capacitor to be unable to continue discharging can be avoided. In this way, the practicability and reliability of the circuit are improved.
[0032] From the above, the circuit can be enabled to have a low loss pre-charge function with a simple circuit implementation, and can also discharge the pre-charge capacitor after power-off to greatly reduce the risk of electric shock. In this way, the effects of reducing pre-charge loss, improving safety, reliability and practicability can be achieved. BRIEF DESCRIPTION OF DRAWINGS
[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.
[0034] Figure 1 A structure diagram of a pre-charge circuit provided by the related art;
[0035] Figure 2 A structure diagram of a first pre-charge and discharge circuit provided by the embodiments of the present application;
[0036] Figure 3 A structure diagram of a second pre-charge and discharge circuit provided by the embodiments of the present application;
[0037] Figure 4 A structure diagram of a third pre-charge and discharge circuit provided by the embodiments of the present application;
[0038] Figure 5 A structure diagram of a fourth pre-charge and discharge circuit provided by the embodiments of the present application;
[0039] Figure 6 A structure diagram of a fifth pre-charge and discharge circuit provided by the embodiments of the present application;
[0040] Figure 7 A structure diagram of a sixth pre-charge and discharge circuit provided by the embodiments of the present application;
[0041] Figure 8 A structure diagram of a power supply system provided by the embodiments of the present application. DETAILED DESCRIPTION
[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.
[0043] Therefore, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.
[0044] It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0045] In the description of the application, it should be noted that the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.
[0046] In the description of the application, it should also be noted that unless otherwise specified and limited, the terms "set", "mount", "connect", "connect" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.
[0047] In the related art, the related art personnel generally set corresponding pre-charging circuits in the power supply system or electronic equipment, and the pre-charging circuits can use elements such as inductors and / or capacitors that can store energy, so that when powered on, the switch tube provided on the pre-charging circuit can be first opened to make the energy storage device pre-charge the inductor and / or capacitor, and then the switch tube is disconnected after pre-charging is completed, and the energy storage device starts to output large current to the power load. In this way, the pre-charging of the capacitor and / or inductor can reduce the impact current in the circuit.
[0048] However, this scheme needs to set an additional control circuit to control the conduction or turn-off of the switch tube provided on the pre-charging circuit, and the control logic is complex, and the loss of the switch tube is high when there is a large current flowing through the pre-charging circuit. In addition, most schemes in the related art do not set a circuit that can discharge the pre-charging capacitor, which may have the risk of electric shock.
[0049] Exemplarily, Figure 1 is a pre-charging circuit commonly used in the related art, such as Figure 1As shown, the battery B0, the capacitor C0, the switch tube Q0 and the resistor R0 are arranged in the pre-charging circuit. Specifically, the first end of the capacitor C0 is connected with the positive pole of the battery B0, the second end of the capacitor C0 is connected with the source of the switch tube Q0, the drain of the switch tube Q0 is connected with the negative pole of the battery B0, and the resistor R0 is connected between the source and the drain of the switch tube Q0 as a current-limiting resistor. The first end of the capacitor C0 and the drain of the switch tube are used to be connected with a subsequent circuit. By inputting a corresponding control signal to the gate of the switch tube Q0, the switch tube Q0 is turned on, thereby realizing the purpose of pre-charging the capacitor C0.
[0050] From Figure 1 As shown in the circuit structure, this scheme needs to arrange an additional control circuit to control the switch tube Q0 to be turned on or turned off, the control logic is complex, and the switch tube Q0 is directly arranged on the main loop, so the loss of the switch tube Q0 is high in the case of large current. In addition, this scheme does not arrange a loop capable of discharging the capacitor C0, and there is a risk of electric shock.
[0051] Therefore, the embodiment of the present application provides a pre-charging and discharging circuit. The pre-charging and discharging circuit is arranged in a circuit and includes a pre-charging capacitor, a pre-charging resistor, a diode and a discharging unit. Specifically, the positive pole of the diode is connected with the positive pole of an energy storage element and the control end of the discharging unit, the negative pole of the diode is connected with the first end of the pre-charging resistor and the first end of the discharging unit respectively, the second end of the pre-charging resistor is connected with the first pole plate of the pre-charging capacitor, the second pole plate of the pre-charging capacitor is connected with the second end of the discharging unit and the negative pole of the energy storage element BAT respectively, and the first pole plate of the pre-charging capacitor is also used to be connected with the positive pole of the energy storage element BAT and the second pole plate of the pre-charging capacitor is also used to be connected with the negative pole of the energy storage element BAT. The pre-charging and discharging circuit can reduce pre-charging loss and improve safety, reliability and practicability.
[0052] The embodiment of the present application takes the pre-charging and discharging circuit applied in the power supply system as an example for description. However, it is not indicated that the embodiment of the present application can only be applied to pre-charging and discharging in the power supply system. For example, the pre-charging and discharging circuit can also be applied to any possible electronic device, and the pre-charging and discharging circuit can also be applied to a high-voltage battery in an energy storage system and a power loop powered by the high-voltage battery, and the embodiment of the present application does not limit this.
[0053] The pre-charging and discharging circuit provided by the embodiment of the present application will be explained and described in detail below.
[0054] Figure 2 A structure schematic diagram of the pre-charging and discharging circuit provided by the present application is shown in the figure. The circuit can be applied to any possible power supply system, energy storage system and / or electronic device. Referring to Figure 2The embodiment of the present application provides a pre-charge discharging circuit 100, which comprises a pre-charge capacitor C1, a pre-charge resistor R1, a diode D and a discharging unit 101.
[0055] The positive electrode of the diode D is used for connecting the positive electrode of an energy storage element BAT and the control end of the discharging unit 101, and the negative electrode of the diode D is connected with the first end of the pre-charge resistor R1 and the first end of the discharging unit 101 respectively.
[0056] The second end of the pre-charge resistor R1 is connected with the first pole plate of the pre-charge capacitor C1, and the second pole plate of the pre-charge capacitor C1 is connected with the second end of the discharging unit 101 and the negative electrode of the energy storage element BAT respectively.
[0057] The first pole plate of the pre-charge capacitor C1 is also used for connecting the positive electrode of the energy storage element BAT respectively, and the second pole plate of the pre-charge capacitor C1 is also used for connecting the negative electrode of the energy storage element BAT respectively.
[0058] The diode D is used for preventing reverse current from flowing back to the positive electrode of the energy storage element BAT and the control end of the discharging unit 101.
[0059] The pre-charge resistor R1 is used for limiting the current size outputted by the energy storage element BAT to the pre-charge capacitor C1.
[0060] The pre-charge capacitor C1 is used for charging under the action of the energy storage element BAT and the pre-charge resistor R1.
[0061] The discharging unit 101 is used for conducting in the case that the energy storage element BAT stops outputting electric energy to the pre-charge capacitor C1, so that the pre-charge capacitor C1 releases electric charge through the pre-charge resistor R1 and the discharging unit 101.
[0062] In addition, the first pole plate of the pre-charge capacitor C1 is also used for connecting the positive electrode of a power loop, and the second pole plate of the pre-charge capacitor C1 is also used for connecting the negative electrode of the power loop respectively.
[0063] Optionally, the reverse current can be the current flowing from the power loop and / or the pre-charge resistor R1 to the negative electrode of the diode D, and can be the current outputted by the power loop, or can be the working current inputted by the energy storage element BAT or other power supply to the power loop, and the embodiment of the present application does not make limitation.
[0064] Exemplarily, continuing to refer to Figure 2 The energy storage element BAT or other power supply can supply power to the power loop through a terminal U+ and a terminal U-, and generally, the terminal U+ can be connected with the positive electrode of the energy storage element BAT, and the terminal U- can be connected with the negative electrode of the energy storage element BAT. The embodiment of the present application does not make limitation.
[0065] Optionally, the power circuit can include any possible power device, for example, the power circuit can be a direct current-direct current (DC-DC) converter, or any other possible voltage boosting converter, voltage reducing converter or direct current-alternating current converter, and the embodiments of the present application do not make any limitation in this aspect.
[0066] In one possible manner, the pre-charge capacitor C1 can also be arranged outside the circuit 100, for example, between the circuit 100 and the power circuit, or at the power input end of the power circuit, that is, the pre-charge capacitor C1 can be a part of the power circuit, and the embodiments of the present application do not make any limitation in this aspect.
[0067] Optionally, the pre-charge capacitor C1 can be an electrolytic capacitor, or any other possible capacitor used for pre-charging the power circuit, and the capacitance of the pre-charge capacitor C1 can be selected according to the actual parameters of the elements in the circuit 100. The embodiments of the present application do not make any limitation in this aspect.
[0068] Optionally, the pre-charge resistor R1 can be used as a current-limiting resistor, and the capacitance of the pre-charge resistor R1 can be selected according to the actual parameters of the elements in the circuit 100.
[0069] Specifically, the discharge unit 101 can be turned on when the energy storage element BAT stops outputting electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1, and the power circuit and / or the terminal U+ does not apply voltage to the pre-charge capacitor C1, so that the pre-charge capacitor C1 releases electric charge through the pre-charge resistor R1 and the discharge unit 101.
[0070] That is, when the energy storage element BAT outputs electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1, and / or the power circuit and / or the terminal U+ applies voltage to the pre-charge capacitor C1, the discharge unit 101 remains in an off state to prevent the pre-charge capacitor C1 from discharging or other abnormal conditions of the circuit 100.
[0071] It is worth noting that, in order to better illustrate the circuit 100 provided by the embodiments of the present application, the working principle of the circuit 100 is explained as follows:
[0072] In the initial state or power-off state, the energy storage element BAT does not output electric energy, and the terminal U+ does not discharge the power circuit and the pre-charge capacitor C1, at this time, the discharge unit 101 is in an on state, so that the pre-charge capacitor C1 has no electric charge or is in a low charge state.
[0073] When the energy storage element BAT starts to output electric energy to the diode D, the current is output to the pre-charge capacitor C1 through the diode D and the pre-charge resistor R1, and the pre-charge capacitor C1 starts pre-charging. After the pre-charge capacitor C1 is pre-charged, working electric energy can be provided to the power circuit through the terminal U+ while providing a voltage to the pre-charge capacitor C1 (at this time, the energy storage element BAT can stop outputting electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1), so that pre-charging can be completed to enable the power circuit to work normally.
[0074] When the power circuit is powered off and the terminal U+ does not supply power to the power circuit and the pre-charge capacitor C1, at this time, the discharging unit 101 starts to conduct to enable the pre-charge capacitor C1 to discharge through the pre-charge resistor R1 and the discharging unit 101 until the pre-charge capacitor C1 is completely discharged or discharged to the off voltage of the discharging unit 101. In this way, the purpose of discharging the pre-charge capacitor C1 after the power circuit completes the working switching to the powered-off state can be achieved.
[0075] It is worth noting that after starting to power on, the energy storage element BAT can directly pre-charge the pre-charge capacitor C1 through the diode D and the pre-charge resistor R1, without the need to set other switching devices, and thus without the need to set a complex control logic. In addition, since there is no switching device in the electric energy transmission path between the energy storage element BAT and the pre-charge capacitor C1, even if the energy storage element BAT outputs a large current, a low loss can be maintained. In addition, in the case of powering off, at this time, the discharging unit 101 is turned on to enable the pre-charge capacitor C1 to discharge through the pre-charge resistor R1 and the discharging unit 101. In this way, the pre-charge capacitor C1 can be completely discharged or in a low charge state, and the risk of electric shock can be greatly reduced.
[0076] In addition, due to the presence of the diode D, when the pre-charge capacitor C1 discharges through the pre-charge resistor R1 and the discharging unit 101, the current flowing through the pre-charge resistor R1 can be prevented from directly flowing into the control end of the discharging unit 101, and thus the problem of causing the discharging unit 101 to be re-off and the pre-charge capacitor C1 to be unable to continue discharging can be avoided. In this way, the practicability and reliability of the circuit 100 are improved.
[0077] In the embodiment of the present application, the pre-charge capacitor C1, the pre-charge resistor R1, the diode D and the discharge unit 101 are arranged in the circuit 100. Specifically, the anode of the diode D is connected to the anode of the energy storage element and the control terminal of the discharge unit 101, and the cathode of the diode D is connected to the first end of the pre-charge resistor R1 and the first end of the discharge unit 101 respectively. The second end of the pre-charge resistor R1 is connected to the first plate of the pre-charge capacitor C1, and the second plate of the pre-charge capacitor C1 is connected to the second end of the discharge unit 101 and the cathode of the energy storage element BAT respectively. The first plate of the pre-charge capacitor C1 is also connected to the anode of the energy storage element BAT, and the second plate of the pre-charge capacitor C1 is also connected to the cathode of the energy storage element BAT.
[0078] After starting power-on, the energy storage element BAT can directly pre-charge the pre-charge capacitor C1 through the diode D and the pre-charge resistor R1, without the need to arrange other switching devices, and thus without the need to arrange complex control logic. Moreover, since there is no switching device in the power transmission path between the energy storage element BAT and the pre-charge capacitor C1, even if the energy storage element BAT outputs a large current, the loss can be kept low. In addition, in the case of power-off, at this time the discharge unit 101 is turned on, so that the pre-charge capacitor C1 can release the charge through the pre-charge resistor R1 and the discharge unit 101. In this way, it can be ensured that the pre-charge capacitor C1 is completely discharged or in a low charge state, and the risk of electric shock can be greatly reduced.
[0079] In addition, due to the presence of the diode D, when the pre-charge capacitor C1 is discharged through the pre-charge resistor R1 and the discharge unit 101, the current flowing through the pre-charge resistor R1 can be prevented from directly flowing into the control terminal of the discharge unit 101, and thus the problem that the discharge unit 101 is turned off again and the pre-charge capacitor C1 cannot continue to discharge can be avoided. In this way, the practicability and reliability of the circuit 100 are improved.
[0080] As can be seen from the above, the circuit 100 can realize the pre-charge function with low loss in a simple circuit, and the pre-charge capacitor C1 can be discharged after power-off to greatly reduce the risk of electric shock. In this way, the effects of reducing pre-charge loss, improving safety, reliability and practicability can be achieved.
[0081] In a possible implementation manner, referring to Figure 3 , the discharge unit 101 includes a first switch tube Q1.
[0082] The first pole of the first switch tube Q1 is connected to the cathode of the diode D and the first end of the pre-charge resistor R1 respectively, the second pole of the first switch tube Q1 is connected to the second plate of the pre-charge capacitor C1 and the cathode of the energy storage element BAT respectively, and the third pole of the first switch tube Q1 is connected to the anode of the energy storage element BAT.
[0083] The first switch tube Q1 is used to conduct when the energy storage element BAT stops outputting electric energy to the pre-charge capacitor C1, so that the pre-charge capacitor C1 releases electric charge through the pre-charge resistor R1 and the discharge unit 101.
[0084] Optionally, the first switch tube Q1 can be a P-channel switch tube, and the first switch tube Q1 can generally be a voltage-controlled switch tube. For example, it can be a PMOS tube, a P-channel IGBT, or any possible device, and the embodiments of the present application do not limit this.
[0085] In the embodiments, the first pole of the first switch tube Q1 can be the source of the PMOS, the second pole of the first switch tube Q1 can be the drain of the PMOS, and the third pole of the first switch tube Q1 can be the gate of the PMOS.
[0086] Specifically, the first switch tube Q1 can be conducted when the energy storage element BAT stops outputting electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1, and the power circuit and / or the terminal U+ does not apply voltage to the pre-charge capacitor C1, so that the pre-charge capacitor C1 releases electric charge through the pre-charge resistor R1 and the discharge unit 101.
[0087] Further, on the basis of Figure 3 , referring to Figure 4 , the discharge unit 101 further includes a first resistor R2.
[0088] The first resistor R2 is connected between the third pole of the first switch tube Q1 and the positive pole of the energy storage element BAT.
[0089] Optionally, the first resistor R2 is used as a drive resistor of the first switch tube Q1 to limit the gate (third pole) current of the first switch tube Q1, so as to protect the gate (third pole) of the first switch tube Q1 from being damaged. The first resistor R2 can also eliminate the voltage oscillation of the gate (third pole) of the first switch tube Q1 due to the parasitic inductance between the gate (third pole) and the source (first pole) of the first switch tube Q1. In this way, the safety and stability of the discharge unit 101 can be improved.
[0090] It is worth noting that when the energy storage element BAT outputs electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1, or the power circuit and / or the terminal U+ applies voltage to the pre-charge capacitor C1, the gate (third pole) voltage of the first switch tube Q1 is pulled high, and at this time, the voltage difference between the source (first pole) and the gate (third pole) of the first switch tube Q1 does not meet the conduction condition of the first switch tube Q1, and the first switch tube Q1 is in an off state.
[0091] However, in the case that the energy storage element BAT stops outputting electric energy to the pre-charge capacitor C1 through the pre-charge resistor R1, and the power loop and / or the terminal U+ does not apply voltage to the pre-charge capacitor C1, the diode D can prevent the current flowing through the pre-charge resistor R1 from directly flowing to the gate (third pole) of the first switch tube Q1, the voltage of the gate (third pole) of the first switch tube Q1 is 0V, at this time, the voltage difference between the source (first pole) and the gate (third pole) of the first switch tube Q1 meets the conduction condition of the first switch tube Q1, and the first switch tube Q1 is in the conduction state.
[0092] In this way, the purpose of enabling the pre-charge capacitor C1 to release the electric charge through the pre-charge resistor R1 and the discharge unit 101 can be achieved.
[0093] In a possible implementation manner, referring to Figure 5 The pre-charge and discharge circuit 100 further includes a slow-start unit 102.
[0094] The first end of the slow-start unit 102 is connected with the anode of the diode D and the control end of the discharge unit 101 respectively, the second end of the slow-start unit 102 is connected with the negative pole of the energy storage element BAT, and the third end of the slow-start unit 102 is connected with the second pole plate of the pre-charge capacitor C1.
[0095] The slow-start unit 102 is configured to slow start, so that the pre-charge capacitor C1 is charged in a delayed manner.
[0096] Optionally, the slow-start unit 102 can include any element such as a capacitor or an inductor that can achieve the purpose of delaying, and the embodiments of the present application do not limit this.
[0097] Specifically, in the case that the slow-start unit 102 is not started, the slow-start unit 102 can also cut off the transmission line between the negative pole of the energy storage element BAT and the second pole plate of the pre-charge capacitor C1, and in the case that the slow-start unit 102 is successfully started, the slow-start unit 102 can also conduct the transmission line between the negative pole of the energy storage element BAT and the second pole plate of the pre-charge capacitor C1. In this way, it can be ensured that the energy storage element BAT does not charge the pre-charge capacitor C1 in the case that the slow-start unit 102 is not started.
[0098] It is worth noting that, since the slow-start unit 102 has the function of slow starting, after the circuit 100 is connected to the energy storage element BAT and the energy storage element BAT starts to output electric energy to the circuit 100, the energy storage element BAT first supplies power to the slow-start unit 102 to slow start the slow-start unit 102, and then starts to charge the pre-charge capacitor C1 after the slow-start unit 102 is successfully started.
[0099] As can be seen, due to the action of the slow start unit 102, the energy storage element BAT will not directly charge the pre-charge capacitor C1 when the circuit 100 is just connected or just starts to supply power, so that the problem of sparking of the connection and / or the wire harness between the energy storage element BAT and the circuit 100 caused by the direct charging of the pre-charge capacitor C1 by the energy storage element BAT when the circuit 100 is connected can be prevented.
[0100] In a possible implementation, referring to Figure 6 The slow start unit 102 comprises a second resistor R3, a third resistor R4, a slow start capacitor C2 and a second switch Q2.
[0101] The first end of the second resistor R3 is connected with the anode of the diode D and the control end of the discharge unit 101 respectively, the second end of the second resistor R3 is connected with the first end of the third resistor R4, the first plate of the slow start capacitor C2 and the first pole of the second switch Q2 respectively, and the second end of the third resistor R4 is connected with the second plate of the slow start capacitor C2, the second pole of the second switch Q2 and the negative pole of the energy storage element BAT respectively.
[0102] The third pole of the second switch Q2 is connected with the second plate of the pre-charge capacitor C1.
[0103] The second resistor R3 and the third resistor R4 are used to divide the voltage output by the energy storage element BAT and transmit the divided voltage to the first pole of the second switch Q2 and the first plate of the slow start capacitor C2.
[0104] The slow start capacitor C2 is used to be charged under the action of the divided voltage, so that the second switch Q2 is slowly started.
[0105] Optionally, the capacitance of the slow start capacitor C2 is generally much smaller than the capacitance of the pre-charge capacitor C1, for example, the capacitance of the slow start capacitor C2 is generally 1-10uF, and the capacitance of the pre-charge capacitor C1 is generally 1000uF, 2000uF or other larger capacitance. Therefore, when the energy storage element BAT charges the slow start capacitor C2 with small capacitance, the problem of sparking will not occur.
[0106] Optionally, the second switch Q2 can be an N-channel switch, and the second switch Q2 can generally be a voltage-controlled switch, such as an NMOS tube, an N-channel IGBT or any possible device, and the embodiments of the present application do not limit this.
[0107] The first pole of the second switch Q2 can be the gate of the NMOS tube, the second pole of the second switch Q2 can be the source of the NMOS tube, and the third pole of the second switch Q2 can be the drain of the NMOS tube.
[0108] It is worth noting that after the circuit 100 is connected to the energy storage element BAT and the energy storage element BAT starts to output power to the circuit 100, since the slow start unit 102 cuts off the line between the negative electrode of the energy storage element BAT and the pre-charge capacitor C1, the energy storage element BAT first supplies power to the second resistor R3 in the slow start unit 102, and then due to the voltage division of the second resistor R3 and the third resistor R4, the voltage applied to the gate (first pole) of the second switch tube Q2 and the first pole plate of the slow start capacitor C2 is divided. In the case that the slow start capacitor C2 has no charge or low voltage, the source (second pole) voltage of the second switch tube Q1 is also low, at this time, the voltage between the source (second pole) and the gate (first pole) of the second switch tube Q1 does not meet the conduction condition of the second switch tube Q2, and the second switch tube Q2 remains off.
[0109] In the case that the slow start capacitor C2 is fully charged or has high voltage, the source (second pole) voltage of the second switch tube Q1 is also high, and in the case that the source (second pole) voltage of the second switch tube Q1 is raised to a level that the voltage between the source (second pole) and the gate (first pole) of the second switch tube Q1 meets the conduction condition of the second switch tube Q2, the second switch tube Q2 starts to conduct to make the line between the negative electrode of the energy storage element BAT and the pre-charge capacitor C1 conductive. In this way, the energy storage element BAT can start to charge the pre-charge capacitor C1.
[0110] In this way, it can be prevented that when the energy storage element BAT is connected to the circuit 100, the connection and / or the wire harness between the energy storage element BAT and the circuit 100 are ignited due to the direct charging of the energy storage element BAT to the pre-charge capacitor C1.
[0111] In a possible implementation, referring to Figure 7 The slow start unit 102 further includes a fourth resistor R5.
[0112] The fourth resistor R5 is connected between the first pole plate of the slow start capacitor C2 and the first pole of the second switch tube Q2.
[0113] Optionally, the fourth resistor R5 is used as a driving resistor of the second switch tube Q2 to limit the current of the gate (first pole) of the second switch tube Q2, so as to protect the gate (first pole) of the second switch tube Q2 from being damaged. The fourth resistor R5 can also eliminate the voltage oscillation of the gate (first pole) due to the parasitic inductance between the gate (first pole) and the source (second pole) of the second switch tube Q2. In this way, the safety and stability of the slow start unit 102 can be improved.
[0114] The following describes a power supply system including the pre-charge and discharge circuit provided in the present application. The specific implementation process and technical effects are described above, and will not be described here.
[0115] Figure 8 is a structural schematic diagram of a power supply system provided by an embodiment of the present application, referring to Figure 8 The power supply system 300 at least includes the power loop 200 and the pre-charge and discharge circuit 100 provided by any of the above embodiments.
[0116] Optionally, the energy storage element BAT can provide the pre-charge power required by the pre-charge through the wire S1, and can also provide the power required by the power loop 200 when working through the wire S2. Generally, the voltage and current of the power output by the energy storage element BAT through the wire S1 are less than the voltage and current of the power output by the energy storage element BAT through the wire S2.
[0117] In addition, the wire S1 has the same function as the positive and negative poles of the energy storage element BAT in the above embodiments. The wire S2 has the same function as the terminal U+ and the terminal U- in the above embodiments, which will not be repeated here.
[0118] In the embodiment, the power loop 200 can be a DC-DC converter, or any other possible power device.
[0119] Exemplarily, in a possible implementation manner, continuing to refer to Figure 8 The power loop 200 includes a plurality of switching tubes, a transformer T, an inductor L, a third capacitor C3 and a fourth capacitor C4.
[0120] Continuing to refer to Figure 8 The power loop 200 includes a switching tube Q3, a switching tube Q4, a switching tube Q5, a switching tube Q6, a switching tube Q7, a switching tube Q8, a switching tube Q9 and a switching tube Q10, and the specific connection relationship is as shown in Figure 8 The connection relationship and the functions of the elements in the power loop 200 will not be repeated here.
[0121] Optionally, the power loop 200 can convert the voltage level of the power output by the energy storage element BAT, and output the converted voltage to other power consumption loads through the bus BUS, which will not be limited here.
[0122] In a possible manner, the power supply system 300 can further include the energy storage element BAT, the wire S1 and / or the wire S2.
[0123] In addition, the power supply system 300 can further include any other possible device to realize any other possible function related to power supply, which will not be limited here.
[0124] The power supply system 300 comprises the pre-charge and discharge circuit 100 provided in the foregoing embodiments, and the power supply system 300 and the pre-charge and discharge circuit 100 belong to the same design concept, and the implementation principles and technical effects are similar, which will not be described here.
[0125] The above merely provides a specific embodiment of the present application, but the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
[0126] The above merely provides a specific embodiment of the present application, but the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims. The above merely provides a specific embodiment of the present application, but the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A pre-charge and discharge circuit, characterized by, The circuit comprises a pre-charge capacitor, a pre-charge resistor, a diode and a discharge unit; a positive electrode of the diode is used to connect a positive electrode of an energy storage element and a control end of the discharge unit, and a negative electrode of the diode is connected with a first end of the pre-charge resistor and a first end of the discharge unit respectively; a second end of the pre-charge resistor is connected with a first plate of the pre-charge capacitor, and a second plate of the pre-charge capacitor is connected with a second end of the discharge unit and a negative electrode of the energy storage element respectively; the first plate of the pre-charge capacitor is also used to connect the positive electrode of the energy storage element respectively, and the second plate of the pre-charge capacitor is also used to connect the negative electrode of the energy storage element respectively; the discharge unit is used to be turned on in the case that the energy storage element stops outputting electric energy to the pre-charge capacitor, so that the pre-charge capacitor releases electric charge through the pre-charge resistor and the discharge unit.
2. The pre-charge discharge circuit of claim 1, wherein, The discharge unit comprises a first switch tube; a first pole of the first switch tube is connected with the negative electrode of the diode and the first end of the pre-charge resistor respectively, a second pole of the first switch tube is connected with the second plate of the pre-charge capacitor and the negative electrode of the energy storage element respectively, and a third pole of the first switch tube is connected with the positive electrode of the energy storage element; wherein the first switch tube is used to be turned on in the case that the energy storage element stops outputting electric energy to the pre-charge capacitor, so that the pre-charge capacitor releases electric charge through the pre-charge resistor and the discharge unit.
3. The pre-charge discharge circuit of claim 2, wherein, The discharge unit further comprises a first resistor; the first resistor is connected between the third pole of the first switch tube and the positive electrode of the energy storage element.
4. The pre-charge discharge circuit of claim 1, wherein, The pre-charge and discharge circuit further comprises a slow start unit; a first end of the slow start unit is connected with the positive electrode of the diode and the control end of the discharge unit respectively, a second end of the slow start unit is connected with the negative electrode of the energy storage element, and a third end of the slow start unit is connected with the second plate of the pre-charge capacitor; wherein the slow start unit is used to start slowly, so that the pre-charge capacitor charges with delay.
5. The pre-charge discharge circuit of claim 4, wherein, The slow start unit comprises a second resistor, a third resistor, a slow start capacitor and a second switch tube; a first end of the second resistor is connected with the positive electrode of the diode and the control end of the discharge unit respectively, a second end of the second resistor is connected with a first end of the third resistor, a first plate of the slow start capacitor and a first pole of the second switch tube respectively, a second end of the third resistor is connected with a second plate of the slow start capacitor, a second pole of the second switch tube and the negative electrode of the energy storage element respectively; a third pole of the second switch tube is connected with the second plate of the pre-charge capacitor.
6. The pre-charge discharge circuit of claim 5, wherein, The slow start unit further comprises a fourth resistor; the fourth resistor is connected between the first plate of the slow start capacitor and the first pole of the second switch tube.
7. The pre-charge discharge circuit of claim 1, wherein, The first plate of the pre-charge capacitor is also used to connect a positive electrode of a power loop, and the second plate of the pre-charge capacitor is also used to connect a negative electrode of the power loop respectively.
8. A power supply system characterized by comprising: The power supply system at least comprises a power loop and the pre-charge and discharge circuit according to any one of claims 1 to 7.
9. The power supply system of claim 8, wherein, The power loop comprises a plurality of switch tubes, a transformer, an inductor, a third capacitor and a fourth capacitor.
10. The power supply system of claim 8, wherein, The power supply system further comprises an energy storage element. The power supply system further comprises an energy storage element.