Contactless power supply switching circuit

Abstract

The utility model discloses a contactless power supply switching circuit, and relates to the technical field of power distribution. According to the main technical scheme, the circuit comprises a bidirectional silicon controlled rectifier Q1, a sampling module, a reference circuit module, an adjusting control module and an auxiliary power supply module, wherein a first main electrode and a second main electrode of the bidirectional silicon controlled rectifier Q1 are respectively connected with an N pole output end of a common mode inductor L1 and a positive pole of an electrolytic capacitor EC5; the sampling module is connected with the L pole output end of the common mode inductor L1; the input end of the reference circuit module is connected with the output end of the sampling module; the input end of the adjusting control module is connected with the output end of the reference circuit module, and the output end of the adjusting control module is connected with the control electrode of the bidirectional silicon controlled rectifier Q1; the auxiliary power supply module is connected with the L pole output end of the common mode inductor L1 and the N pole output end of the common mode inductor L1, and the output end of the auxiliary power supply module is connected with the input end of the reference circuit module and the input end of the adjustment control module. The purpose of reducing the risk of misconduction between the common mode inductor L1 and the electrolytic capacitor EC5 is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of power distribution, in particular to a contactless power switching circuit. Background Art

[0002] High power switching power supply such as Figure 1 As shown in the figure, when the AC input is 220V, the AC power is rectified by capacitor CX1, inductor L1, and rectifier bridge D13, and then filtered by electrolytic capacitors EC2 and EC5, generating a voltage of +310V. When the AC input is 110V, the AC power is rectified by capacitor CX1, inductor L1, rectifier bridge D13, and filtered by electrolytic capacitors EC2 and EC5, generating a voltage of +150V, which does not meet the starting power supply standard. In this case, it is necessary to connect the N-pole output terminal of common-mode inductor L1 to the positive terminal of electrolytic capacitor EC5.

[0003] When pin 4 of the common-mode inductor L1 and the positive electrode of the electrolytic capacitor EC5 are in the conductive state, the positive half-wave current of AC110V (the voltage at the live wire end) is rectified by the rectifier bridge D13 and charges the positive electrode of the electrolytic capacitor EC2. The voltage is then loaded to the neutral line, making the voltage across the positive and negative electrodes of the electrolytic capacitor EC2 150V. The negative half-wave current of AC110V (the voltage at the neutral line end) is rectified by the rectifier bridge D13 and charges the positive electrode of the electrolytic capacitor EC5. The voltage is then loaded to the live wire, making the voltage across the positive and negative electrodes of the electrolytic capacitor EC5 150V. At this point, the total voltage from the positive electrode of the electrolytic capacitor EC2 to the ground is equal to the voltage across the positive and negative electrodes of the electrolytic capacitor EC2 plus the voltage across the positive and negative electrodes of the electrolytic capacitor EC5, which is 300V, thus meeting the starting power supply standard.

[0004] Currently, switching between AC110V and AC220V is primarily achieved by using a relay to open or close the connection between common-mode inductor L1 and electrolytic capacitor EC5. However, relays are mechanical switches and pose a significant risk of malfunction when exposed to vibration. Utility Model Content

[0005] The purpose of the utility model is to provide a contactless power switching circuit, which solves the problem that the existing relay has a large risk of malfunction when vibrating.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A contactless power switching circuit includes a bidirectional thyristor (SCR) Q1, a sampling module, a reference circuit module, a regulation control module, and an auxiliary power supply module. The first main electrode of the bidirectional thyristor Q1 is used to be connected to the N-pole output end of a common-mode inductor L1, and the second main electrode of the bidirectional thyristor Q1 is used to be connected to the positive electrode of an electrolytic capacitor EC5. The bidirectional thyristor Q1 is used to switch the common-mode inductor L1 and the electrolytic capacitor EC5 on or off. The input end of the sampling module is used to be connected to the L-pole output end of the common-mode inductor L1. The input end of the reference circuit module is connected to the output end of the sampling module. The input end of the regulation control module is connected to the output end of the reference circuit module, and the output end of the regulation control module is connected to the control electrode of the bidirectional thyristor Q1. The input end of the auxiliary power supply module is used to be connected to both the L-pole output end and the N-pole output end of the common-mode inductor L1, and the output end of the auxiliary power supply module is connected to both the input end of the reference circuit module and the input end of the regulation control module.

[0008] A further solution is: the sampling module includes a resistor R26; one end of the resistor R26 is used to connect to the L-pole output end of the common-mode inductor L1; the other end of the resistor R26 is connected to the input end of the reference circuit module.

[0009] A further solution is: the reference circuit module includes a comparator U2A, a comparator U2B, a resistor R13, a resistor R14, a resistor R7, a capacitor C19, an electrolytic capacitor EC1, a diode D2 and a voltage regulator U4; pin 2 of the comparator U2A, one end of the capacitor C19, one end of the Ri'anzu R13, and the cathode of the diode D2 are all connected to the other end of the resistor R26; pin 4 of the comparator U2A, the anode of the voltage regulator U4, the cathode of the electrolytic capacitor EC1, the anode of the diode D2, the other end of the resistor R13, and the other end of the capacitor C19 are all connected to the reference circuit module; the reference circuit module includes a comparator U2A, a comparator U2B, a resistor R13, a resistor R14, a resistor R7, a capacitor C19, a diode D2 and the other end of the resistor R13. The negative electrode of the electrolytic capacitor EC5 is connected; the pin 3 of the comparator U2A is connected to the pin 5 of the comparator U2B, the cathode of the voltage regulator U4, the reference electrode of the voltage regulator U4, and one end of the resistor R14; the pin 8 of the comparator U2A, the other end of the resistor R14, and one end of the resistor R27 are all connected to the output end of the auxiliary power supply; the pin 1 of the comparator U2A, the positive electrode of the electrolytic capacitor EC1, and the other end of the resistor R27 are all connected to the pin 6 of the comparator U2B; the pin 7 of the comparator U2B is connected to the input end of the regulation control module.

[0010] A further solution is: the regulation control module includes a resistor R16, a resistor R23, a resistor R24, a resistor R25, a capacitor C3, a light-emitting diode LED1 and an optocoupler U3; one end of the resistor R24 is used to connect to the L-pole output end of the common-mode inductor L1; the other end of the resistor R24 is connected to one end of the resistor R25 and one end of the capacitor C3; the other end of the resistor R25 is connected to pin 6 of the optocoupler U3; the other end of the capacitor C3 is used to connect to the negative electrode of the electrolytic capacitor EC5; one end of the resistor R16 and one end of the resistor R23 are both connected to the output end of the auxiliary power supply; the other end of the resistor R16 is connected to the positive electrode of the light-emitting diode LED1; the negative electrode of the light-emitting diode LED1 and pin 2 of the optocoupler U3 are both connected to pin 7 of the comparator U2B; the other end of the resistor R23 is connected to pin 1 of the optocoupler U3; and pin 4 of the optocoupler U3 is connected to the control electrode of the bidirectional thyristor Q1.

[0011] A further solution is: the auxiliary power supply module includes a power control chip U5, a diode D8, a diode D9, a diode 11, a diode D12, an inductor L2, an electrolytic capacitor EC3, an electrolytic capacitor EC4, a capacitor C6, a capacitor C17 and a resistor R29; the positive electrode of the diode D8 is connected to one end of the inductor L2, the positive electrode of the electrolytic capacitor EC3, pin 8 of the comparator U2A, the other end of the resistor R14, one end of the resistor R27, one end of the resistor R16, and one end of the resistor R23; the negative electrode of the diode D8 is connected to one end of the capacitor C6 and pin 1 of the power control chip U5; the other end of the capacitor C6, the other end of the inductor L2, one end of the capacitor C17, one end of the resistor R29, and the negative electrode of the diode D9 are all connected to the power control chip U5 is connected to pin 2; the other end of the capacitor C17 is connected to pin 3 of the power control chip U5; the other end of the resistor R29 is connected to pin 4 of the power control chip U5; the positive electrode of the diode D12 is used to be connected to the L-pole output end of the common-mode inductor L1; the positive electrode of the diode D11 is used to be connected to the N-pole output end of the common-mode inductor L1; the negative electrode of the diode D11, the negative electrode of the diode D12, pin 5 of the power control chip U5, pin 6 of the power control chip U5, pin 7 of the power control chip U5, and pin 8 of the power control chip U5 are all connected to the positive electrode of the electrolytic capacitor EC4; the negative electrode of the electrolytic capacitor EC4, the positive electrode of the diode D9, and the negative electrode of the electrolytic capacitor EC3 are all used to be connected to the negative electrode of the electrolytic capacitor EC5.

[0012] A further solution is: the contactless power switching circuit also includes a shutdown reset module; the input end of the shutdown reset module is connected to the positive electrode of the electrolytic capacitor EC1 and the positive electrode of the diode D8; the sampling module also includes a resistor R12, a resistor R28, a capacitor C20 and a diode D1; one end of the resistor R12 is used to be connected to the L-pole output end of the common-mode inductor L1; the other end of the resistor R12 is connected to one end of the resistor R28, one end of the capacitor C20, the negative electrode of the diode D1, and the input end of the shutdown reset module; the other end of the resistor R28, the other end of the capacitor C20, the positive electrode of the diode D1, and the output end of the shutdown reset module are all connected to the negative electrode of the electrolytic capacitor EC3.

[0013] A further solution is: the shutdown reset module includes a transistor Q4, a transistor Q9, a resistor R4, a resistor R9, a resistor R10, a resistor R15, an electrolytic capacitor EC9, a diode D3, a diode D14 and a diode D15; one end of the resistor R15 is connected to the positive electrode of the electrolytic capacitor EC1; the other end of the resistor R15 is connected to the positive electrode of the diode D3; the cathode of the diode D3 is connected to one end of the resistor R4 and the collector of the transistor Q9; the other end of the resistor R4 is connected to the positive electrode of the electrolytic capacitor EC9, the negative electrode of the diode D14, and the collector of the transistor Q9; One end of the resistor R10 is connected; the anode of the diode D14 is connected to the anode of the diode D8; the negative electrode of the electrolytic capacitor EC9 is used to be connected to the negative electrode of the electrolytic capacitor EC5; the other end of the resistor R10 is connected to the collector of the transistor Q4, one end of the resistor R9, and the positive electrode of the diode D15; the negative electrode of the diode D15 is connected to the base of the transistor Q9; the base of the transistor Q4 is connected to the other end of the resistor R12; the emitter of the transistor Q4, the other end of the resistor R9, and the emitter of the transistor Q9 are all connected to the negative electrode of the electrolytic capacitor EC3.

[0014] A further solution is: the power control chip is CR3215A.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The first main electrode of the bidirectional thyristor Q1 is connected to the N-pole output terminal of the common-mode inductor L1, and the second main electrode of the bidirectional thyristor Q1 is connected to the positive electrode of the electrolytic capacitor EC5. The input of the sampling module is connected to the L-pole output terminal of the common-mode inductor L1. The input of the reference circuit module is connected to the output of the sampling module. The input of the regulation control module is connected to the output of the reference circuit module, and the output of the regulation control module is connected to the control electrode of the bidirectional thyristor Q1. The input of the auxiliary power supply module is connected to both the L-pole output terminal and the N-pole output terminal of the common-mode inductor L1, and the output of the auxiliary power supply module is connected to both the input of the reference circuit module and the input of the regulation control module. This reduces the risk of misconnection between the N-pole output terminal of the common-mode inductor L1 and the positive electrode of the electrolytic capacitor EC5. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a circuit structure topology diagram of an existing high-power switching power supply;

[0018] Figure 2 This is an electrical block diagram of a contactless power switching circuit in this embodiment;

[0019] Figure 3 This is a circuit structure topology diagram of a contactless power switching circuit in this embodiment connected to an existing high-power switching power supply.

[0020] Markings and corresponding parts names in the accompanying drawings:

[0021] 100-sampling module; 200-reference circuit module; 300-regulation control module; 400-auxiliary power supply module. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings.

[0023] Example

[0024] This embodiment provides a contactless power switching circuit, such as Figure 2As shown, it includes a bidirectional thyristor Q1, a sampling module 100, a reference circuit module 200, a regulation control module 300 and an auxiliary power supply module 400, wherein the first main electrode of the bidirectional thyristor Q1 is used to be connected to the N-pole output terminal of the common-mode inductor L1, and the second main electrode of the bidirectional thyristor Q1 is used to be connected to the positive electrode of the electrolytic capacitor EC5; the bidirectional thyristor Q1 is used to turn on or off the common-mode inductor L1 and the electrolytic capacitor EC5; the input end of the sampling module 100 is used to be connected to the L-pole output terminal of the common-mode inductor L1; the reference circuit The input end of the module 200 is connected to the output end of the sampling module 100; the input end of the regulation control module 300 is connected to the output end of the reference circuit module 200, and the output end of the regulation control module is connected to the control electrode of the bidirectional thyristor Q1; the input end of the auxiliary power supply module 400 is used to be connected to the L-pole output end and the N-pole output end of the common-mode inductor L1, and the output end of the auxiliary power supply module 400 is connected to the input end of the reference circuit module 200 and the input end of the regulation control module 300.

[0025] like Figure 3 As shown, in this embodiment, the sampling module 100 includes a resistor R26 ; one end of the resistor R26 is used to connect to the L-pole output end of the common-mode inductor L1 ; the other end of the resistor R26 is connected to the input end of the reference circuit module 200 .

[0026] like Figure 3 As shown, in this embodiment, the reference circuit module 200 includes a comparator U2A, a comparator U2B, a resistor R13, a resistor R14, a resistor R7, a capacitor C19, an electrolytic capacitor EC1, a diode D2 and a voltage regulator U4; pin 2 of the comparator U2A, one end of the capacitor C19, one end of the R13, and the cathode of the diode D2 are all connected to the other end of the resistor R26; pin 4 of the comparator U2A, the anode of the voltage regulator U4, the cathode of the electrolytic capacitor EC1, the anode of the diode D2, the other end of the resistor R13, and the other end of the capacitor C19 are all connected to the R26. The negative electrode of the electrolytic capacitor EC5 is connected; the pin 3 of the comparator U2A is connected to the pin 5 of the comparator U2B, the cathode of the voltage regulator U4, the reference electrode of the voltage regulator U4, and one end of the resistor R14; the pin 8 of the comparator U2A, the other end of the resistor R14, and one end of the resistor R27 are all connected to the output end of the auxiliary power supply; the pin 1 of the comparator U2A, the positive electrode of the electrolytic capacitor EC1, and the other end of the resistor R27 are all connected to the pin 6 of the comparator U2B; the pin 7 of the comparator U2B is connected to the input end of the regulation control module 300.

[0027] like Figure 3As shown, in this embodiment, the regulation control module 300 includes a resistor R16, a resistor R23, a resistor R24, a resistor R25, a capacitor C3, a light-emitting diode LED1 and an optocoupler U3; one end of the resistor R24 is used to be connected to the L-pole output end of the common-mode inductor L1; the other end of the resistor R24 is connected to one end of the resistor R25 and one end of the capacitor C3; the other end of the resistor R25 is connected to pin 6 of the optocoupler U3; the other end of the capacitor C3 is used to be connected to the negative electrode of the electrolytic capacitor EC5; one end of the resistor R16 and one end of the resistor R23 are both connected to the output end of the auxiliary power supply; the other end of the resistor R16 is connected to the positive electrode of the light-emitting diode LED1; the negative electrode of the light-emitting diode LED1 and pin 2 of the optocoupler U3 are both connected to pin 7 of the comparator U2B; the other end of the resistor R23 is connected to pin 1 of the optocoupler U3; and pin 4 of the optocoupler U3 is connected to the control electrode of the bidirectional thyristor Q1.

[0028] like Figure 3 As shown, in this embodiment, the auxiliary power supply module 400 includes a power supply control chip U5, a diode D8, a diode D9, a diode 11, a diode D12, an inductor L2, an electrolytic capacitor EC3, an electrolytic capacitor EC4, a capacitor C6, a capacitor C17 and a resistor R29; the positive electrode of the diode D8 is connected to one end of the inductor L2, the positive electrode of the electrolytic capacitor EC3, pin 8 of the comparator U2A, the other end of the resistor R14, one end of the resistor R27, one end of the resistor R16, and one end of the resistor R23; the negative electrode of the diode D8 is connected to one end of the capacitor C6 and pin 1 of the power supply control chip U5; the other end of the capacitor C6, the other end of the inductor L2, one end of the capacitor C17, one end of the resistor R29, and the negative electrode of the diode D9 are all connected to the power supply control chip U5. Pin 2 of the chip U5; the other end of the capacitor C17 is connected to pin 3 of the power control chip U5; the other end of the resistor R29 is connected to pin 4 of the power control chip U5; the positive electrode of the diode D12 is used to be connected to the L-pole output end of the common-mode inductor L1; the positive electrode of the diode D11 is used to be connected to the N-pole output end of the common-mode inductor L1; the negative electrode of the diode D11, the negative electrode of the diode D12, pin 5 of the power control chip U5, pin 6 of the power control chip U5, pin 7 of the power control chip U5, and pin 8 of the power control chip U5 are all connected to the positive electrode of the electrolytic capacitor EC4; the negative electrode of the electrolytic capacitor EC4, the positive electrode of the diode D9, and the negative electrode of the electrolytic capacitor EC3 are all used to be connected to the negative electrode of the electrolytic capacitor EC5.

[0029] like Figure 3As shown, in this embodiment, the contactless power switching circuit further includes a shutdown reset module; the input end of the shutdown reset module is connected to the positive electrode of the electrolytic capacitor EC1 and the positive electrode of the diode D8; the sampling module 100 further includes a resistor R12, a resistor R28, a capacitor C20 and a diode D1; one end of the resistor R12 is used to be connected to the L-pole output end of the common-mode inductor L1; the other end of the resistor R12 is connected to one end of the resistor R28, one end of the capacitor C20, the negative electrode of the diode D1, and the input end of the shutdown reset module; the other end of the resistor R28, the other end of the capacitor C20, the positive electrode of the diode D1, and the output end of the shutdown reset module are all connected to the negative electrode of the electrolytic capacitor EC3.

[0030] like Figure 3 As shown, in this embodiment, the shutdown reset module includes a transistor Q4, a transistor Q9, a resistor R4, a resistor R9, a resistor R10, a resistor R15, an electrolytic capacitor EC9, a diode D3, a diode D14 and a diode D15; one end of the resistor R15 is connected to the positive electrode of the electrolytic capacitor EC1; the other end of the resistor R15 is connected to the positive electrode of the diode D3; the cathode of the diode D3 is connected to one end of the resistor R4 and the collector of the transistor Q9; the other end of the resistor R4 is connected to the positive electrode of the electrolytic capacitor EC9, the negative electrode of the diode D14, and the collector of the transistor Q9; One end of the resistor R10 is connected; the anode of the diode D14 is connected to the anode of the diode D8; the negative electrode of the electrolytic capacitor EC9 is used to be connected to the negative electrode of the electrolytic capacitor EC5; the other end of the resistor R10 is connected to the collector of the transistor Q4, one end of the resistor R9, and the positive electrode of the diode D15; the negative electrode of the diode D15 is connected to the base of the transistor Q9; the base of the transistor Q4 is connected to the other end of the resistor R12; the emitter of the transistor Q4, the other end of the resistor R9, and the emitter of the transistor Q9 are all connected to the negative electrode of the electrolytic capacitor EC3.

[0031] like Figure 3 As shown, in this embodiment, the power control chip is CR3215A.

[0032] The working principle of the contactless power switching circuit provided in this embodiment is as follows:

[0033] The first main electrode of triac Q1 and the anode of diode D11 are connected to the N-pole output terminal of common-mode inductor L1 (pin 4 of common-mode inductor L1). One end of resistor R26, one end of resistor R24, the anode of diode D12, and one end of resistor R12 are connected to the L-pole output terminal of common-mode inductor L1 (pin 2 of common-mode inductor L1). The second main electrode of triac Q1 is connected to the anode of electrolytic capacitor EC5. Pin 4 of comparator U2A, the anode of voltage regulator U4, the cathode of electrolytic capacitor EC1, the anode of diode D2, the other end of resistor R13, the other end of capacitor C19, the other end of capacitor C3, the other end of resistor R28, the other end of capacitor C20, the anode of diode D1, the emitter of transistor Q4, the other end of resistor R9, the emitter of transistor Q9, the cathode of electrolytic capacitor EC3, the anode of diode D9, the cathode of electrolytic capacitor EC4, and the cathode of electrolytic capacitor EC5 are connected. Pin 4 of optocoupler U3 is connected to the control electrode of bidirectional thyristor Q1.

[0034] Auxiliary power module 400 includes power control chip U5, diode D8, diode D9, diode 11, diode D12, inductor L2, electrolytic capacitor EC3, electrolytic capacitor EC4, capacitor C6, capacitor C17, and resistor R29. The output voltage of auxiliary power module 400 is 12.5V. The voltage output from the L-pole output terminal (pin 2 of common-mode inductor L1) and the N-pole output terminal (pin 4 of common-mode inductor L1) of common-mode inductor L1 is rectified and filtered by diode D12, diode D11, and electrolytic capacitor EC4 before providing power to power control chip U5.

[0035] Resistor R26 is a sampling resistor. The voltage output from the L-pole output terminal of common-mode inductor L1 (pin 2 of common-mode inductor L1) is divided by resistors R26 and R13, rectified by diode D2, and filtered by capacitor C19 before being applied to pin 2 of comparator U2A. Both comparators U2A and U2B use LM393 comparators. Comparator U2A functions as a comparator, while comparator U2B functions as a driver. Resistor R14 is a bias resistor. Voltage regulator U4 is a TL431 voltage regulator IC, providing a 2.5V reference voltage for pins 3 and 5 of comparator U2A and U2B, respectively. Resistor R27 and electrolytic capacitor EC1 act as a delay circuit, providing a delay when comparator U2A flips. Optocoupler U3 provides isolation from high voltages.

[0036] When AC110V is input, the AC current, after passing through resistor R26 and diode D2, generates a 1.5V voltage at pin 2 of comparator U2A. This 1.5V voltage is less than the 2.5V reference voltage at pin 3 of comparator U2A, causing pin 1 of comparator U2A to output a high level. This high level is greater than the 2.5V reference voltage at pin 5 of comparator U2B, causing pin 7 of comparator U2B to output a low level. At this point, LED1 illuminates, and current flows through resistor R23 into optocoupler U3, and then through pin 1 of optocoupler U3 into pin 7 of comparator U2B. This turns on pins 4 and 6 of optocoupler U3, further turning on triac Q1, thereby increasing the voltage between the positive terminal of electrolytic capacitor EC2 and ground to 300V DC.

[0037] When 220V AC is input, the voltage generated at comparator U2A's pin 2, after passing through resistor R26 and diode D2, is greater than the 2.5V reference voltage at comparator U2A's pin 3, causing comparator U2A's pin 1 to output a low level. This low level is less than the 2.5V reference voltage at comparator U2B's pin 5, causing comparator U2B's pin 7 to output a high level, also setting optocoupler U3's pin 1 to a high level. At this point, no current flows through optocoupler U3's pins 1 and 2, disconnecting pins U3's pins 4 and 6, and thus turning off triac Q1.

[0038] When the input is repeatedly switched between AC110V and AC220V, since the sampling module 100 is always in the working state and the input is AC power, the bidirectional thyristor Q1 will not be always turned on.

[0039] The shutdown reset module includes transistors Q4, Q9, resistors R4, R9, R10, R15, electrolytic capacitor EC9, diode D3, diode D14, and diode D15. Transistors Q4, D15, Q9, D3, and R15 form a shutdown discharge circuit for 110V AC input. This discharges the charge in electrolytic capacitor EC1 after shutdown, reducing the risk of malfunction. Resistors R4, R9, and R10 serve as bias resistors for transistor Q9. Diode D15 increases the conduction voltage of transistor Q9. Electrolytic capacitor EC9 is used for charge storage. Diode D14 blocks reverse discharge. When AC power is applied, it is rectified by resistor R12 and diode D1 and applied to the base of transistor Q4, turning it on. At this point, the voltage applied to diode D15 drops below the threshold, insufficient to conduct diode D15 and transistor Q9, leaving pin 6 of comparator U2B unaffected. When the power is turned off, the base of transistor Q4 is de-energized, preventing conduction. Diode D14 reverse-blocks discharge, and the charge stored in electrolytic capacitor EC9 discharges more slowly. This causes the voltage at the collector of transistor Q4 to rise, saturating transistor Q9 and conducting. This allows the voltage in electrolytic capacitor EC1 to discharge to ground through resistor R15, diode D3, and transistor Q9, completing the shutdown reset.

[0040] Although the present invention has been described herein with reference to a number of illustrative embodiments thereof, it will be understood that numerous other modifications and implementations may be devised by those skilled in the art that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope of the present disclosure, the drawings, and the claims, numerous variations and modifications may be made to the components and / or arrangement of the subject combination arrangement. In addition to variations and modifications to the components and / or arrangement, other uses will also be apparent to those skilled in the art.

Claims

1. A contactless power switching circuit, characterized in that: include: A bidirectional thyristor Q1, wherein a first main electrode of the bidirectional thyristor Q1 is connected to the N-pole output terminal of the common-mode inductor L1, and a second main electrode of the bidirectional thyristor Q1 is connected to the positive electrode of the electrolytic capacitor EC5; the bidirectional thyristor Q1 is used to turn on or off the common-mode inductor L1 and the electrolytic capacitor EC5; A sampling module (100), wherein the input end of the sampling module (100) is used to be connected to the L-pole output end of the common-mode inductor L1; A reference circuit module (200), wherein an input end of the reference circuit module (200) is connected to an output end of the sampling module (100); An adjustment control module (300), wherein the input end of the adjustment control module (300) is connected to the output end of the reference circuit module (200), and the output end of the adjustment control module is connected to the control electrode of the bidirectional thyristor Q1; An auxiliary power supply module (400) is provided, wherein the input end of the auxiliary power supply module (400) is connected to both the L-pole output end and the N-pole output end of the common-mode inductor L1, and the output end of the auxiliary power supply module (400) is connected to both the input end of the reference circuit module (200) and the input end of the regulation control module (300).

2. The contactless power switching circuit according to claim 1, wherein: The sampling module (100) includes a resistor R26; One end of the resistor R26 is used to connect to the L-pole output end of the common-mode inductor L1; The other end of the resistor R26 is connected to the input end of the reference circuit module (200).

3. The contactless power switching circuit according to claim 2, wherein: The reference circuit module (200) includes a comparator U2A, a comparator U2B, a resistor R13, a resistor R14, a resistor R7, a capacitor C19, an electrolytic capacitor EC1, a diode D2 and a voltage regulator U4; Pin 2 of the comparator U2A, one end of the capacitor C19, one end of the resistor R13, and the cathode of the diode D2 are all connected to the other end of the resistor R26; Pin 4 of the comparator U2A, the anode of the voltage regulator U4, the cathode of the electrolytic capacitor EC1, the anode of the diode D2, the other end of the resistor R13, and the other end of the capacitor C19 are all used to connect to the cathode of the electrolytic capacitor EC5; Pin 3 of the comparator U2A is connected to pin 5 of the comparator U2B, the cathode of the voltage regulator U4, the reference electrode of the voltage regulator U4, and one end of the resistor R14; Pin 8 of the comparator U2A, the other end of the resistor R14, and one end of the resistor R27 are all connected to the output end of the auxiliary power supply; Pin 1 of the comparator U2A, the positive electrode of the electrolytic capacitor EC1, and the other end of the resistor R27 are all connected to pin 6 of the comparator U2B; Pin 7 of the comparator U2B is connected to the input end of the regulation control module (300).

4. The contactless power switching circuit according to claim 3, wherein: The regulating control module (300) comprises a resistor R16, a resistor R23, a resistor R24, a resistor R25, a capacitor C3, a light emitting diode LED1 and an optical coupler U3; One end of the resistor R24 is used to connect to the L-pole output end of the common-mode inductor L1; The other end of the resistor R24 is connected to one end of the resistor R25 and one end of the capacitor C3; The other end of the resistor R25 is connected to pin 6 of the optocoupler U3; The other end of the capacitor C3 is used to connect to the negative electrode of the electrolytic capacitor EC5; One end of the resistor R16 and one end of the resistor R23 are both connected to the output end of the auxiliary power supply; The other end of the resistor R16 is connected to the positive electrode of the light emitting diode LED1; The cathode of the light emitting diode LED1 and the pin 2 of the optocoupler U3 are connected to the pin 7 of the comparator U2B; The other end of the resistor R23 is connected to pin 1 of the optocoupler U3; Pin 4 of the optocoupler U3 is connected to the control electrode of the bidirectional thyristor Q1.

5. The contactless power switching circuit according to claim 4, wherein: The auxiliary power supply module (400) comprises a power supply control chip U5, a diode D8, a diode D9, a diode 11, a diode D12, an inductor L2, an electrolytic capacitor EC3, an electrolytic capacitor EC4, a capacitor C6, a capacitor C17 and a resistor R29; The anode of the diode D8 is connected to one end of the inductor L2, the anode of the electrolytic capacitor EC3, pin 8 of the comparator U2A, the other end of the resistor R14, one end of the resistor R27, one end of the resistor R16, and one end of the resistor R23; The cathode of the diode D8 is connected to one end of the capacitor C6 and pin 1 of the power control chip U5; The other end of the capacitor C6, the other end of the inductor L2, one end of the capacitor C17, one end of the resistor R29, and the cathode of the diode D9 are all connected to pin 2 of the power control chip U5; The other end of the capacitor C17 is connected to pin 3 of the power control chip U5; The other end of the resistor R29 is connected to pin 4 of the power control chip U5; The anode of the diode D12 is used to be connected to the L-pole output end of the common-mode inductor L1; The anode of the diode D11 is used to be connected to the N-pole output end of the common-mode inductor L1; The cathode of the diode D11, the cathode of the diode D12, pin 5 of the power control chip U5, pin 6 of the power control chip U5, pin 7 of the power control chip U5, and pin 8 of the power control chip U5 are all connected to the positive electrode of the electrolytic capacitor EC4; The cathode of the electrolytic capacitor EC4, the anode of the diode D9, and the cathode of the electrolytic capacitor EC3 are all used to be connected to the cathode of the electrolytic capacitor EC5.

6. The contactless power switching circuit according to claim 5, wherein: It also includes a shutdown reset module; The input end of the shutdown reset module is connected to the positive electrode of the electrolytic capacitor EC1 and the positive electrode of the diode D8; The sampling module (100) further includes a resistor R12, a resistor R28, a capacitor C20 and a diode D1; One end of the resistor R12 is used to connect to the L-pole output end of the common-mode inductor L1; The other end of the resistor R12 is connected to one end of the resistor R28, one end of the capacitor C20, the cathode of the diode D1, and the input end of the shutdown reset module; The other end of the resistor R28 , the other end of the capacitor C20 , the positive electrode of the diode D1 , and the output end of the shutdown reset module are all connected to the negative electrode of the electrolytic capacitor EC3 .

7. The contactless power switching circuit according to claim 6, wherein: The shutdown reset module includes a transistor Q4, a transistor Q9, a resistor R4, a resistor R9, a resistor R10, a resistor R15, an electrolytic capacitor EC9, a diode D3, a diode D14 and a diode D15; One end of the resistor R15 is connected to the positive electrode of the electrolytic capacitor EC1; The other end of the resistor R15 is connected to the anode of the diode D3; The cathode of the diode D3 is connected to one end of the resistor R4 and the collector of the transistor Q9; The other end of the resistor R4 is connected to the positive electrode of the electrolytic capacitor EC9, the negative electrode of the diode D14, and one end of the resistor R10; The anode of the diode D14 is connected to the anode of the diode D8; The negative electrode of the electrolytic capacitor EC9 is used to be connected to the negative electrode of the electrolytic capacitor EC5; The other end of the resistor R10 is connected to the collector of the transistor Q4, one end of the resistor R9, and the positive electrode of the diode D15; The cathode of the diode D15 is connected to the base of the transistor Q9; The base of the transistor Q4 is connected to the other end of the resistor R12; The emitter of the transistor Q4, the other end of the resistor R9, and the emitter of the transistor Q9 are all connected to the negative electrode of the electrolytic capacitor EC3.

8. The contactless power switching circuit according to claim 5, wherein: The power control chip is CR3215A.

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