Control circuit

Abstract

The invention provides a control circuit, relates to the technical field of driving control, and aims to solve the problem of low stability of a conventional control circuit. The control circuit comprises a first power supply comprising a first positive electrode and a first negative electrode; the positive electrode of the input end of the first photoelectric coupler is connected with the first positive electrode, and the negative electrode of the input end of the first photoelectric coupler is connected with the first negative electrode; the first capacitor is bridged between the positive electrode of the input end of the first photoelectric coupler and the negative electrode of the input end of the first photoelectric coupler; the second power supply comprises a second positive electrode and a second negative electrode, and the second positive electrode is connected with the output end positive electrode of the first photoelectric coupler; the grid electrode of the first MOS tube is connected with the negative electrode of the output end of the first photoelectric coupler; compared with a conventional arc extinguishing or pre-charging circuit, the circuit is suitable for a control circuit which has the characteristics of high voltage, independence, small heating amount and the like, and can greatly improve the stability and reliability of a high-voltage power supply in a system at the conduction moment.

Description

Technical Field

[0001] The present invention relates to the field of drive control technology, and in particular to a control circuit. Background Art

[0002] The energy in electric-powered underwater unmanned vehicle products is provided by high-voltage power battery packs, and its loads include propulsion motors, instrument electrical components, etc. When the underwater unmanned vehicle works in sequence, in order to prevent crosstalk between electrical components, most load input ends use large-capacity capacitors for filtering, and the high-voltage battery energy is connected in sequence through relays or switch switching devices. Due to the influence of capacitor impedance characteristics, it is in a short-circuit state at the moment of power-on, and the power circuit will generate an instantaneous high peak current (ie "surge current"). Although the peak current pulse width is narrow, the peak value is dozens of times larger than the steady-state current, causing the front-pole relay transistor to break down due to overcurrent, or the switch switching device to generate local high temperature due to overcurrent, causing the local contact material to melt and cool rapidly before separation, which in turn causes the switch switching device contacts to stick together, making it impossible to cut off the power supply in sequence. At the same time, it may cause instantaneous power loss in parallel electrical components, thereby affecting the stable and reliable operation of the product and causing catastrophic consequences.

[0003] In order to prevent the relay or switch switching device from being damaged or losing power due to the instantaneous overcurrent of large-capacity load during power switching, the current electric-powered underwater unmanned vehicle uses a resistor pre-charging method to achieve circuit protection function, such as Figure 1 As shown, the first switch K1 is closed, and the resistor R and the large-capacity capacitor C form an RC charging circuit to realize slow charging of the capacitor C. When the voltage V0 of the capacitor C is approximately equal to the voltage of the input terminal +Vcc, the second switch K2 is closed. Since the internal resistance of the second switch K2 is much smaller than the charging resistor R, the resistor R in the charging circuit is bypassed, realizing the function of pre-charging the capacitor C to prevent overcurrent protection, and the circuit starts to work normally.

[0004] The resistor pre-charging overcurrent impact protection circuit has the remarkable characteristics of simple structure and few components, but it also has the following disadvantages:

[0005] a) This circuit is only applicable to low voltage power supply, not when the VCC terminal is high voltage (greater than 300V);

[0006] b) When the first switch and the second switch are disconnected, there is no discharge circuit and the generated back electromotive force may damage the switch device;

[0007] c) The first switch and the second switch are in series mode. After normal power supply, both the first switch and the second switch need to work normally, which reduces the fault tolerance of the circuit. Summary of the invention

[0008] The present invention aims to at least solve the problem of low stability of conventional control circuits.

[0009] To this end, the present invention provides a control circuit.

[0010] The present invention provides a control circuit, comprising: a first power supply, comprising a first positive electrode and a first negative electrode; a first photoelectric coupler, wherein the positive electrode of the input end of the first photoelectric coupler is connected to the first positive electrode, and the negative electrode of the input end of the first photoelectric coupler is connected to the first negative electrode; a first capacitor, which is connected between the positive electrode of the input end of the first photoelectric coupler and the negative electrode of the input end of the first photoelectric coupler; a second power supply, comprising a second positive electrode and a second negative electrode, wherein the second positive electrode is connected to the positive electrode of the output end of the first photoelectric coupler; a first MOS (Metal-Oxide-Semiconductor) tube, wherein the gate of the first MOS tube is connected to the negative electrode of the output end of the first photoelectric coupler; a load capacitor, wherein the positive electrode of the load capacitor is connected to the drain of the first MOS tube, and the negative electrode of the load capacitor is connected to the second negative electrode; and a second photoelectric coupler. A coupler, the positive electrode of the input end of the second photocoupler is connected to the first positive electrode, the negative electrode of the input end of the second photocoupler is connected to the first negative electrode, and the positive electrode of the output end of the second photocoupler is connected to the second positive electrode; a second capacitor is connected between the positive electrode and the negative electrode of the input end of the second photocoupler; a second MOS tube, the gate of the second MOS tube is connected to the negative electrode of the output end of the second photocoupler, the source of the second MOS tube is connected to the second positive electrode, and the drain of the second MOS tube is connected to the positive electrode of the load capacitor; a load, the positive electrode of the load is connected to the positive electrode of the load capacitor, and the negative electrode of the load is connected to the negative electrode of the load capacitor; a ninth resistor is connected between the drain of the second MOS tube and the positive electrode of the load capacitor; a first switch is arranged between the first power supply and the first photocoupler; and a second switch is arranged between the first power supply and the second photocoupler.

[0011] The control circuit provided by the present invention includes two circuit modules, namely a pre-charging circuit and a MOS tube control circuit. The pre-charging circuit is composed of a second photoelectric coupler, a second capacitor, a second MOS tube, a ninth resistor, and a load capacitor. The MOS tube control circuit is composed of a first photoelectric coupler, a first capacitor, a first MOS tube, a load, etc. In this way, during the working process, two processes are included: a load capacitor charging process and a main circuit stable operation process. During the load capacitor charging process, the second switch is closed, the second photoelectric coupler is turned on, the A point level is pulled up, the second MOS tube is turned on, and then the second power supply completes the charging of the load capacitor through the ninth resistor. When the load capacitor is charged to balance, the first switch is closed, so that the first photoelectric coupler is turned on, thereby completing the connection of the main circuit and the load stable operation. The present invention forms a primary charging circuit by connecting a ninth resistor and a load capacitor in series in a control circuit, forms an RC charging loop at the initial stage of powering on the high-voltage power supply, plays a role of current limiting and arc extinguishing, and after the large-capacity capacitor is pre-charged, the first photocoupler is turned on, and the characteristics of low impedance and simple driving after the first MOS tube is turned on are utilized to open the MOS tube main loop circuit, wherein the main loop circuit is also a circuit with a load stably working formed by the second positive electrode, the first MOS tube, the load, and the second negative electrode. Since the load capacitor is fully charged, when the first MOS tube is turned on, the existence of the load capacitor slows down the speed of voltage rise, thereby reducing the possibility of voltage spikes, and plays a role in preventing the high-voltage circuit from damaging the switch at the moment of turning on. Compared with the conventional existing arc extinguishing or pre-charging circuit, the present invention has the characteristics of being suitable for high voltage, autonomy, and low heat generation, and can greatly improve the stability and reliability of the high-voltage power supply in the system at the moment of turning on.

[0012] In some technical solutions, optionally, the control circuit further includes a load resistor, and two ends of the load resistor are respectively connected to the positive electrode of the load capacitor and the negative electrode of the load capacitor.

[0013] In this technical solution, the control circuit also includes a large-capacitance discharge circuit, so that when the first MOS tube and the second MOS tube are disconnected, there is residual high voltage and a large amount of charge on the large-capacity load capacitor, which is discharged through the load resistor, thereby preventing other circuit components from being damaged by excessive voltage and extending the service life of the circuit.

[0014] In some technical solutions, optionally, the control circuit also includes: a third resistor, arranged between the gate of the first MOS tube and the negative output terminal of the first photocoupler; a seventh resistor, arranged between the gate of the second MOS tube and the negative output terminal of the second photocoupler.

[0015] In this technical solution, by providing the third resistor and the seventh resistor, a voltage dividing function in the loop can be achieved, thereby protecting the gates of the first MOS tube and the second MOS tube from damage.

[0016] In some technical schemes, optionally, the control circuit also includes: a second resistor, one end of the second resistor is connected between the third resistor and the negative electrode of the output end of the first photocoupler, and the other end of the second resistor is connected to the positive electrode of the load capacitor; a sixth resistor, one end of the sixth resistor is connected between the seventh resistor and the negative electrode of the output end of the second photocoupler, and the other end of the sixth resistor is connected to the positive electrode of the load capacitor.

[0017] In this technical solution, the second resistor is connected in parallel with the first MOS tube, and the sixth resistor is connected in parallel with the second MOS tube. The parallel shunting can reduce the current of the first MOS tube and the second MOS tube, thereby further protecting the first MOS tube and the second MOS tube.

[0018] In some technical solutions, optionally, the control circuit also includes: a first diode, the anode of the first diode is connected to the cathode of the output terminal of the first photocoupler, and the cathode of the first diode is connected to the gate of the first MOS tube; a third diode, the anode of the third diode is connected to the cathode of the output terminal of the second photocoupler, and the cathode of the third diode is connected to the gate of the second MOS tube.

[0019] In this technical solution, since the diode has the characteristic of unidirectional conduction, the first diode and the third diode are provided mainly to prevent the high voltage power supply from damaging the output ends of the first photocoupler and the second photocoupler, thereby improving the life of the first photocoupler and the second photocoupler.

[0020] In some technical schemes, optionally, the control circuit also includes: a fourth resistor, wherein both ends of the fourth resistor are respectively connected to the drain of the first MOS tube and the cathode of the first diode; and an eighth resistor, wherein both ends of the eighth resistor are respectively connected to the drain of the second MOS tube and the cathode of the third diode.

[0021] In some technical solutions, optionally, the control circuit also includes: a second diode, the anode of the second diode is connected to the drain of the first MOS tube, and the cathode of the second diode is connected to the gate of the first MOS tube; a fourth diode, the anode of the fourth diode is connected to the drain of the second MOS tube, and the cathode of the fourth diode is connected to the gate of the second MOS tube.

[0022] In this technical solution, the second diode and the fourth diode mainly prevent the first MOS tube and the second MOS tube from generating a back electromotive force between the gate and the drain at the moment of switching action, thereby preventing the first MOS tube and the second MOS tube from being over-voltage-broken and causing permanent damage.

[0023] In some technical solutions, optionally, the control circuit also includes: a first resistor, wherein both ends of the first resistor are respectively connected between the positive input terminal of the first photocoupler and the first switch; and a fifth resistor, wherein both ends of the fifth resistor are respectively connected between the positive input terminal of the second photocoupler and the second switch.

[0024] In this technical solution, during the closing process of the first photocoupler and the second photocoupler, the first resistor and the fifth resistor mainly play the role of current limiting protection, smoothing the drive signal, improving circuit stability and controlling the switching speed, thereby reducing potential failure risks.

[0025] In some technical schemes, optionally, a voltage converter is arranged between the second positive electrode and the positive electrode of the output end of the first photocoupler, a voltage converter is arranged between the second positive electrode and the positive electrode of the output end of the second photocoupler, the voltage between the second positive electrode and the second negative electrode is A1, the voltage converted by the voltage converter is A2, the difference between A2 and A1 is greater than or equal to 10V and less than or equal to 20V; for example, the difference between A2 and A1 is 15V.

[0026] In some technical solutions, optionally, the first MOS tube and the second MOS tube both include one of the following or a combination thereof: N-channel enhancement MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), P-channel enhancement MOSFET, N-channel depletion MOSFET and P-channel depletion MOSFET.

[0027] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] Figure 1 shows a structural schematic diagram of a related control circuit;

[0030] Figure 2 One of the structural schematic diagrams of the control circuit provided by the embodiment of the present invention is shown;

[0031] Figure 3 A second structural schematic diagram of a control circuit provided by an embodiment of the present invention is shown;

[0032] Figure 4 The third structural schematic diagram of the control circuit provided by the embodiment of the present invention is shown.

[0033] in, Figures 2 to 4The corresponding relationship between the reference numerals and the component names is as follows:

[0034] 1 control circuit, 11 pre-charging circuit, 12 MOS tube control circuit, 13 capacitor discharge circuit, 14 first power supply, 15 second power supply, 152 second positive electrode, 154 second negative electrode, 16 voltage converter. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0037] like Figure 2 and Figure 3As shown, the control circuit 1 provided by the present invention includes: a first power supply 14, including a first positive electrode and a first negative electrode (as is well known in the art, a power supply structure is usually represented by three vertical lines of different lengths, and one end of the longest vertical line is the positive electrode, and one end of the shortest vertical line is the negative electrode); a first photocoupler V1, the positive electrode of the input end of the first photocoupler V1 is connected to the first positive electrode, and the negative electrode of the input end of the first photocoupler V1 is connected to the first negative electrode; a first capacitor C1 is connected between the positive electrode of the input end of the first photocoupler V1 and the negative electrode of the input end of the first photocoupler V1; a second power supply 15, including a second positive electrode 152 and a second negative electrode 154, and the second positive electrode 152 is connected to the positive electrode of the output end of the first photocoupler V1; a first MOS tube Q1, and the gate of the first MOS tube Q1 is connected to the negative electrode of the output end of the first photocoupler V1; a load capacitor CL, the positive electrode of the load capacitor CL is connected to the drain of the first MOS tube Q1, and the negative electrode of the load capacitor CL is connected to the second negative electrode 154; a second photocoupler a first photocoupler V2, wherein the positive electrode of the input end of the second photocoupler V2 is connected to the first positive electrode, the negative electrode of the input end of the second photocoupler V2 is connected to the first negative electrode, and the positive electrode of the output end of the second photocoupler V2 is connected to the second positive electrode 152; a second capacitor C2 is connected between the positive electrode and the negative electrode of the input end of the second photocoupler V2; a second MOS transistor Q2, wherein the gate of the second MOS transistor Q2 is connected to the negative electrode of the output end of the second photocoupler V2, the source of the second MOS transistor Q2 is connected to the second positive electrode 152, and the drain of the second MOS transistor Q2 is connected to the positive electrode of the load capacitor CL; a load Load, wherein the positive electrode of the load Load is connected to the positive electrode of the load capacitor CL, and the negative electrode of the load Load is connected to the negative electrode of the load capacitor CL; a ninth resistor R9 is connected between the drain of the second MOS transistor Q2 and the positive electrode of the load capacitor CL; a first switch K1 is arranged between the first power supply 14 and the first photocoupler V1; and a second switch K2 is arranged between the first power supply 14 and the second photocoupler V2.

[0038] The control circuit 1 provided by the present invention includes two circuit modules, namely, a pre-charging circuit 11 and a MOS tube control circuit 12. The pre-charging circuit 11 is composed of a second photoelectric coupler V2, a second capacitor C2, a second MOS tube Q2, a ninth resistor R9, and a load capacitor CL. The MOS tube control circuit 12 is composed of a first photoelectric coupler V1, a first capacitor C1, a first MOS tube Q1, a load Load, etc. In this way, during the working process, there are two processes including the charging process of the load capacitor CL and the stable operation of the main circuit. During the charging process of the load capacitor CL, the second switch K2 is closed, the second photoelectric coupler V2 is turned on, the level of point A is pulled up, the second MOS tube Q2 is turned on, and then the second power supply completes the charging of the load capacitor CL through the ninth resistor R9. When the load capacitor CL is charged to balance, the first switch K1 is closed, so that the first photoelectric coupler V1 is turned on, thereby completing the connection of the main circuit and the stable operation of the load Load. The present invention forms a primary charging circuit by connecting the ninth resistor R9 and the load capacitor CL in series in the control circuit 1, and forms an RC charging loop at the initial stage of the high-voltage power supply power-on, which plays the role of current limiting and arc extinguishing. When the large-capacity load capacitor CL is pre-charged, the first photocoupler V1 is turned on, and the first MOS tube Q1 is turned on by using the characteristics of low impedance and simple driving after the first MOS tube Q1 is turned on, so as to open the main loop circuit of the first MOS tube Q1, wherein the main loop circuit is also a circuit in which the load Load forms a stable operation of the second positive electrode 152, the first MOS tube Q1, the load Load, and the second negative electrode 154. Since the load capacitor CL is fully charged, when the first MOS tube Q1 is turned on, the existence of the load capacitor CL will slow down the speed of voltage rise, thereby reducing the possibility of voltage spikes, and playing the role of preventing the high-voltage circuit from damaging the switch at the moment of turning on. Compared with the conventional existing arc extinguishing or pre-charging circuit, the present invention has the characteristics of being suitable for high voltage, autonomous, and low heat generation, and can greatly improve the stability and reliability of the high-voltage power supply in the system at the moment of turning on.

[0039] In some technical solutions, optionally, the control circuit 1 further includes a load resistor RL, and two ends of the load resistor RL are respectively connected to the positive electrode of the load capacitor CL and the negative electrode of the load capacitor CL.

[0040] In this technical solution, the control circuit 1 also includes a capacitor discharge circuit 13, so that when the first MOS tube Q1 and the second MOS tube Q2 are disconnected, there is residual high voltage and a large amount of charge on the large-capacity load capacitor CL, which is discharged through the load resistor RL, thereby preventing other circuit components from being damaged by excessively high voltage and extending the service life of the circuit.

[0041] In some technical solutions, optionally, the control circuit 1 further includes: a third resistor R3, arranged between the gate of the first MOS tube Q1 and the negative output terminal of the first photocoupler V1; a seventh resistor R7, arranged between the gate of the second MOS tube Q2 and the negative output terminal of the second photocoupler V2.

[0042] In this technical solution, by providing the third resistor R3 and the seventh resistor R7, a voltage dividing function in the loop can be achieved, thereby protecting the gates of the first MOS transistor Q1 and the second MOS transistor Q2 from damage.

[0043] In some technical schemes, optionally, the control circuit 1 also includes: a second resistor R2, one end of the second resistor R2 is connected between the third resistor R3 and the negative electrode of the output end of the first photocoupler V1, and the other end of the second resistor R2 is connected to the positive electrode of the load capacitor CL; a sixth resistor R6, one end of the sixth resistor R6 is connected between the seventh resistor R7 and the negative electrode of the output end of the second photocoupler V2, and the other end of the sixth resistor R6 is connected to the positive electrode of the load capacitor CL.

[0044] In this technical solution, the second resistor R2 is connected in parallel with the first MOS transistor Q1, and the sixth resistor R6 is connected in parallel with the second MOS transistor Q2. The parallel shunting can reduce the current of the first MOS transistor Q1 and the second MOS transistor Q2, thereby further protecting the first MOS transistor Q1 and the second MOS transistor Q2.

[0045] In some technical solutions, optionally, the control circuit 1 also includes: a first diode D1, the anode of the first diode D1 is connected to the cathode of the output terminal of the first photocoupler V1, and the cathode of the first diode D1 is connected to the gate of the first MOS tube Q1; a third diode D3, the anode of the third diode D3 is connected to the cathode of the output terminal of the second photocoupler V2, and the cathode of the third diode D3 is connected to the gate of the second MOS tube Q2.

[0046] In this technical solution, since the diode has the characteristic of unidirectional conduction, the first diode D1 and the third diode D3 are provided mainly to prevent the high voltage power supply from damaging the output ends of the first photocoupler V1 and the second photocoupler V2, thereby improving the life of the first photocoupler V1 and the second photocoupler V2.

[0047] In some technical schemes, optionally, the control circuit 1 also includes: a fourth resistor R4, wherein both ends of the fourth resistor R4 are respectively connected to the drain of the first MOS tube Q1 and the cathode of the first diode D1; an eighth resistor R8, wherein both ends of the eighth resistor R8 are respectively connected to the drain of the second MOS tube Q2 and the cathode of the third diode D3.

[0048] In some technical solutions, optionally, the control circuit 1 also includes: a second diode D2, the anode of the second diode D2 is connected to the drain of the first MOS tube Q1, and the cathode of the second diode D2 is connected to the gate of the first MOS tube Q1; a fourth diode D4, the anode of the fourth diode D4 is connected to the drain of the second MOS tube Q2, and the cathode of the fourth diode D4 is connected to the gate of the second MOS tube Q2.

[0049] In this technical solution, the second diode D2 and the fourth diode D4 mainly prevent the first MOS tube Q1 and the second MOS tube Q2 from generating a back electromotive force between the gate and the drain at the moment of switching action, thereby preventing the first MOS tube Q1 and the second MOS tube Q2 from being over-voltage-broken and causing permanent damage.

[0050] In some technical schemes, optionally, the control circuit 1 also includes: a first resistor R1, wherein both ends of the first resistor R1 are respectively connected between the positive input terminal of the first photocoupler V1 and the first switch K1; and a fifth resistor R5, wherein both ends of the fifth resistor R5 are respectively connected between the positive input terminal of the second photocoupler V2 and the second switch K2.

[0051] In this technical solution, during the closing process of the first photocoupler V1 and the second photocoupler V2, the first resistor R1 and the fifth resistor R5 mainly play the role of current limiting protection, smoothing the drive signal, improving circuit stability and controlling the switching speed, thereby reducing potential failure risks.

[0052] In some technical solutions, optionally, as Figure 4 As shown, a voltage converter 16 is arranged between the second positive electrode 152 and the positive electrode of the output end of the first photocoupler V1, and a voltage converter 16 is arranged between the second positive electrode 152 and the positive electrode of the output end of the second photocoupler V2. The voltage between the second positive electrode 152 and the second negative electrode 154 is A1, and the voltage converted by the voltage converter 16 is A2. The difference between A2 and A1 is greater than or equal to 10V and less than or equal to 20V; for example, the difference between A2 and A1 is 15V.

[0053] In some technical solutions, optionally, the first MOS transistor Q1 and the second MOS transistor Q2 each include one of the following or a combination thereof: an N-channel enhancement MOSFET, a P-channel enhancement MOSFET, an N-channel depletion MOSFET, and a P-channel depletion MOSFET.

[0054] Based on the technical problems raised in the background technology, another embodiment of the present invention provides a control circuit 1 and a control method thereof. The control circuit 1 of this embodiment is mainly used to eliminate the defects and shortcomings of the high-voltage overcurrent impact protection circuit in the existing electro-powered underwater unmanned vehicle products or civilian large-capacity capacitive load Load products. The control circuit 1 of the present invention can also be called a compact space transient high-voltage arc extinguishing circuit, including: a pre-charging circuit 11 connected in series in the loop, a MOS tube control circuit 12 based on high voltage, and a large capacitor discharge circuit 13.

[0055] The pre-charging circuit 11 connected in series in the loop includes a second MOS tube Q2, a ninth resistor R9 and a large-capacity load capacitor CL, and is specifically connected as follows: the source of the second MOS tube Q2 is connected to the second positive electrode 152 of the high-voltage power supply (that is, the above-mentioned second power supply 15), the drain of the second MOS tube Q2 is connected to the ninth resistor R9, the other end of the ninth resistor R9 is connected to the positive electrode of the large-capacity load capacitor CL, and the negative electrode of the large-capacity load capacitor CL is connected to the second negative electrode 154 of the high-voltage power supply.

[0056] The MOS tube control circuit 12 based on high voltage includes a first resistor R1, a first capacitor C1, a first photocoupler V1, a second resistor R2, a third resistor R3, a first diode D1, a second diode D2, a fourth resistor R4, and a first MOS tube Q1. The specific connection is: one end of the first resistor R1 is connected to the first positive electrode of the first power supply 14, and the other end is connected to the positive electrode of the input end of the first photocoupler V1, the second capacitor C2 is connected across the positive electrode and the negative electrode of the input end of the second photocoupler V2, the positive electrode of the output end of the first photocoupler V1 is connected to the second positive electrode 152, and of course, it can also be connected to the second positive electrode 152 through a voltage converter 16 (micro DC / DC module converter), the output voltage of the voltage converter 16 is about 15V higher than the voltage of the second power supply 15, and one end of the second resistor R2 is connected to the negative electrode of the output end of the first photocoupler V1. and one end of the third resistor R3, and the other end is connected to the positive electrode of the load capacitor CL, the other end of the third resistor R3 is connected to the positive electrode of the first diode D1, the other end of the first diode D1 is respectively connected to the gate of the first MOS transistor Q1, the negative electrode of the second diode D2 and one end of the fourth resistor R4, the source of the first MOS transistor Q1 is connected to the second positive electrode 152 of the high-voltage power supply, the drain of the first MOS transistor Q1 is respectively connected to the positive electrode of the second diode D2, the other end of the fourth resistor R4 and one end of the load resistor RL, and the other end of the load resistor RL is connected to the second negative electrode 154 of the high-voltage power supply. The connection relationship among the fifth resistor R5, the second capacitor C2, the second photocoupler V2, the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the first diode D1 and the second diode D2 is as follows: Figure 2 The principle is the same as the above connection method.

[0057] The large capacitance discharge loop 13 includes a load resistor RL and a load capacitor CL. Specifically, the load resistor RL and the large capacitance load capacitor CL are connected in parallel, one end of which is connected to the drain of the first MOS transistor Q1, and the other end is connected to the second negative electrode 154 of the high voltage power supply.

[0058] The method for implementing the above compact space transient high voltage arc extinguishing circuit comprises the following steps:

[0059] Step 1: When the main control chip controls the second switch K2 to a high level, the second photocoupler V2 is turned on. Figure 2 The level of point A is pulled high. R8 ≈(R8·U 高压 ) / (R7+R8+R9+RL-0.7V), the second MOS tube Q2 is turned on, and then the high-voltage power supply completes charging of the large-capacity load capacitor CL through the ninth resistor R9.

[0060] Step 2: When the load capacitor CL is charged to equilibrium, the main control chip controls the first switch K1 to close, so that the first photocoupler V1 is turned on. R4 ≈(R4·U 高压 ) / (R3+R4+RL-0.7V), the first MOS tube Q1 is turned on, and the connection of the high-voltage power supply main circuit is completed, wherein the third resistor R3 and the seventh resistor R7 respectively play the role of voltage division in the circuit and protection of the gates of the first MOS tube Q1 and the second MOS tube Q2, the first diode D1 and the third diode D3 mainly prevent the high-voltage power supply from damaging the output ends of the first photocoupler V1 and the second photocoupler V2, and the second diode D2 and the fourth diode D4 mainly prevent the first MOS tube Q1 and the second MOS tube Q2 from generating a back electromotive force between the gate and the drain at the moment of the switching action.

[0061] Step 3: When the first MOS transistor Q1 and the second MOS transistor Q2 are disconnected, there is residual high voltage and a large amount of charge on the large-capacity load capacitor CL, which is discharged through the load resistor RL.

[0062] The beneficial effect of the control circuit of this embodiment is that it can eliminate the defects and shortcomings of the high-voltage overcurrent impact protection circuit in the existing electric-powered underwater unmanned vehicle products or civilian large-capacity capacitive load Load products, thereby achieving the fundamental purpose of reducing the design complexity and improving the working stability and reliability of the power supply system.

[0063] In the present invention, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0064] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0065] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control circuit, characterized in that: include: A first power source includes a first positive electrode and a first negative electrode; A first photoelectric coupler, wherein a positive electrode of an input terminal of the first photoelectric coupler is connected to the first positive electrode, and a negative electrode of an input terminal of the first photoelectric coupler is connected to the first negative electrode; A first capacitor is connected between the positive input terminal of the first photocoupler and the negative input terminal of the first photocoupler; A second power supply includes a second positive electrode and a second negative electrode, wherein the second positive electrode is connected to the positive electrode of the output terminal of the first photoelectric coupler; A first MOS transistor, wherein a gate of the first MOS transistor is connected to a negative electrode of an output end of the first photocoupler; A load capacitor, wherein the positive electrode of the load capacitor is connected to the drain of the first MOS transistor, and the negative electrode of the load capacitor is connected to the second negative electrode; A second photoelectric coupler, wherein a positive electrode of an input terminal of the second photoelectric coupler is connected to the first positive electrode, a negative electrode of an input terminal of the second photoelectric coupler is connected to the first negative electrode, and a positive electrode of an output terminal of the second photoelectric coupler is connected to the second positive electrode; A second capacitor is connected between the positive input terminal and the negative input terminal of the second photocoupler; a second MOS transistor, wherein the gate of the second MOS transistor is connected to the negative electrode of the output terminal of the second photocoupler, the source of the second MOS transistor is connected to the second positive electrode, and the drain of the second MOS transistor is connected to the positive electrode of the load capacitor; A load, wherein the positive electrode of the load is connected to the positive electrode of the load capacitor, and the negative electrode of the load is connected to the negative electrode of the load capacitor; a ninth resistor, connected between the drain of the second MOS tube and the positive electrode of the load capacitor; A first switch, arranged between the first power supply and the first photocoupler; The second switch is arranged between the first power supply and the second photocoupler.

2. The control circuit according to claim 1, characterized in that: Also includes: A load resistor, wherein two ends of the load resistor are respectively connected to the positive electrode of the load capacitor and the negative electrode of the load capacitor.

3. The control circuit according to claim 1, characterized in that: Also includes: A third resistor is arranged between the gate of the first MOS tube and the negative electrode of the output end of the first photocoupler; The seventh resistor is arranged between the gate of the second MOS tube and the negative electrode of the output end of the second photocoupler.

4. The control circuit according to claim 3, characterized in that: Also includes: a second resistor, one end of the second resistor being connected between the third resistor and the negative electrode of the output end of the first photocoupler, and the other end of the second resistor being connected to the positive electrode of the load capacitor; A sixth resistor, one end of the sixth resistor is connected between the seventh resistor and the negative electrode of the output end of the second photocoupler, and the other end of the sixth resistor is connected to the positive electrode of the load capacitor.

5. The control circuit according to claim 1, characterized in that: Also includes: a first diode, wherein an anode of the first diode is connected to a cathode of an output terminal of the first photocoupler, and a cathode of the first diode is connected to a gate of the first MOS transistor; A third diode, wherein the anode of the third diode is connected to the cathode of the output end of the second photocoupler, and the cathode of the third diode is connected to the gate of the second MOS tube.

6. The control circuit according to claim 5, characterized in that: Also includes: a fourth resistor, wherein two ends of the fourth resistor are respectively connected to the drain of the first MOS tube and the cathode of the first diode; An eighth resistor, wherein two ends of the eighth resistor are respectively connected to the drain of the second MOS tube and the cathode of the third diode.

7. The control circuit according to claim 1, characterized in that: Also includes: a second diode, wherein an anode of the second diode is connected to the drain of the first MOS transistor, and a cathode of the second diode is connected to the gate of the first MOS transistor; A fourth diode, wherein an anode of the fourth diode is connected to the drain of the second MOS tube, and a cathode of the fourth diode is connected to the gate of the second MOS tube.

8. The control circuit according to claim 1, characterized in that: Also includes: A first resistor, wherein two ends of the first resistor are respectively connected between the positive input terminal of the first photocoupler and the first switch; A fifth resistor, two ends of which are respectively connected between the positive input terminal of the second photoelectric coupler and the second switch.

9. The control circuit according to any one of claims 1 to 8, characterized in that: A voltage converter is arranged between the second positive electrode and the positive electrode of the output end of the first photoelectric coupler, and the voltage converter is arranged between the second positive electrode and the positive electrode of the output end of the second photoelectric coupler. The voltage between the second positive electrode and the second negative electrode is A1, and the voltage converted by the voltage converter is A2. The difference between A2 and A1 is greater than or equal to 10V and less than or equal to 20V.

10. The control circuit according to any one of claims 1 to 8, characterized in that: The first MOS transistor and the second MOS transistor each include one of the following or a combination thereof: an N-channel enhancement MOSFET, a P-channel enhancement MOSFET, an N-channel depletion MOSFET, and a P-channel depletion MOSFET.

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