Polyphase AC Power Supply Control Circuit and Solid State Relay

Abstract

The present application relates to a multiphase AC power supply control circuit and a solid-state relay. The circuit includes at least one MOSFET circuit and at least one gate drive power supply circuit correspondingly connected to the MOSFET circuit. The MOSFET circuit is connected in series in any one-phase AC power supply path. It further includes an input control circuit, a MOSFET drive circuit, and a zero-crossing detection circuit. The zero-crossing detection circuit is connected to the multiphase AC power supply path. The zero-crossing detection circuit outputs a zero-crossing signal when the multiphase alternating current output by the multiphase AC power supply path passes through zero. The MOSFET drive circuit, under the trigger of the zero-crossing signal and based on the enable signal sent by the input control circuit, controls the gate drive power supply circuit to provide a drive power signal to the corresponding MOSFET circuit. The MOSFET circuit controls the corresponding AC power supply path to conduct based on the drive power signal, solving the problem that the impact current during the on / off process of the circuit is too large and is not conducive to the long-term use of the MOSFET.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and particularly to a multiphase AC power supply control circuit and a solid-state relay. Background Art

[0002] In the field of power electronics, the power-on control of high-power devices generally uses contactors, which have the advantages of low cost, mature technology, and simple control methods. However, in some specific fields, the disadvantages of contactors limit their applications, such as large volume, high noise, large starting and stopping inrush current, and high self-power consumption. With the development of MOSFET (metal-oxide-semiconductor field-effect transistor) from silicon (Si) material to silicon carbide (SiC) material, the advantages of MOSFET devices, such as high thermal conductivity, high critical breakdown electric field, high carrier mobility, low power consumption, and high efficiency, have made them widely used. Currently, MOSFET devices are mainly used in DC fields, such as DC solid-state relays based on MOSFETs, and the application of SiC-based MOSFETs in electric vehicles. For two-phase and three-phase AC power supply circuits, since the voltage and current values at the moment of circuit conduction are uncertain, it is possible that the current value is exactly at the peak at the moment of conduction, resulting in an excessive inrush current during the circuit on-off process, which is not conducive to the long-term use of MOSFETs. Summary of the Invention

[0003] In this embodiment, a multiphase AC power supply control circuit and a solid-state relay are provided to solve the problem in the related technology that the inrush current during the circuit on-off process is too large and not conducive to the long-term use of MOSFETs.

[0004] In the first aspect, in this embodiment, a multiphase AC power supply control circuit is provided. The circuit includes at least one MOSFET circuit and at least one gate drive power supply circuit correspondingly connected to the MOSFET circuit. The MOSFET circuit is connected in series in any phase AC power supply path. The circuit further includes an input control circuit, a MOSFET drive circuit, and a zero-crossing detection circuit. The zero-crossing detection circuit is connected to the multiphase AC power supply path;

[0005] The zero-crossing detection circuit outputs a zero-crossing signal when the multiphase alternating current output by the multiphase AC power supply path passes through zero;

[0006] The MOSFET drive circuit, under the trigger of the zero-crossing signal and based on the enable signal sent by the input control circuit, controls the gate drive power supply circuit to provide a drive power signal to the corresponding MOSFET circuit;

[0007] The MOSFET circuit controls the corresponding AC power supply path to conduct based on the drive power signal.

[0008] In some of these embodiments, the MOSFET driving circuit includes a flip-flop, which outputs a turn-on / off control signal corresponding to the enable signal when receiving the zero-crossing signal, and the turn-on / off control signal is used to turn on or off the connection between the gate driving power supply circuit and the corresponding MOSFET circuit.

[0009] In some of these embodiments, the gate driving power supply circuit outputs the driving power signal through transformer isolation, and the ground of the gate driving power supply circuit is connected to the source electrode of the MOSFET in the corresponding MOSFET circuit.

[0010] In some of these embodiments, the poly-phase AC power supply path includes a first-phase power supply path and a second-phase power supply path. The zero-crossing detection circuit includes a resistor R4, a resistor R5, and a bidirectional optocoupler chip U1. One end of the resistor R4 is connected to the input end of the first-phase power supply path, the other end of the resistor R4 is connected to the first end of the bidirectional optocoupler chip U1, the second end of the bidirectional optocoupler chip U1 is connected to the input end of the second-phase power supply path, the third end of the bidirectional optocoupler chip U1 is connected to the power supply VDD, the fourth end of the bidirectional optocoupler chip U1 outputs the zero-crossing signal and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded.

[0011] In some of these embodiments, the poly-phase AC power supply control circuit includes a first MOSFET circuit and a first gate driving power supply circuit.

[0012] The first MOSFET circuit is connected in series between the input end and the output end of the first-phase power supply path. The ground of the first gate driving power supply circuit is connected to the source electrode of the first MOSFET circuit, and the input end and the output end of the second-phase power supply path are directly connected.

[0013] The MOSFET driving circuit includes a D flip-flop U2, an optocoupler chip U3, a light-emitting diode LED1, and a resistor R9. The clock terminal of the D flip-flop U2 accesses the zero-crossing signal, the D terminal of the D flip-flop U2 is connected to the input control circuit, the power supply terminal of the D flip-flop U2 is connected to the power supply VDD, the GND terminal of the D flip-flop U2 is grounded, the output terminal of the D flip-flop U2 is connected to the anode of the input terminal of the optocoupler chip U3, the cathode of the input terminal of the optocoupler chip U3 is grounded through the light-emitting diode LED1 and the resistor R9, the collector of the output terminal of the optocoupler chip U3 accesses the driving power signal V G -1, and the emitter of the output terminal of the optocoupler chip U3 outputs a signal G-CTRL1 and accesses the gate of the first MOSFET circuit.

[0014] In some of these embodiments, the polyphase AC power supply control circuit includes a first MOSFET circuit, a second MOSFET circuit, a first gate drive power supply circuit, and a second gate drive power supply circuit;

[0015] The first MOSFET circuit is connected in series between the input end and the output end of the first-phase power supply path, and the ground of the first gate drive power supply circuit is connected to the source electrode of the first MOSFET circuit; the second MOSFET circuit is connected in series between the input end and the output end of the second-phase power supply path, and the ground of the second gate drive power supply circuit is connected to the source electrode of the second MOSFET circuit;

[0016] The MOSFET drive circuit includes a D flip-flop U2, an optocoupler chip U3, an optocoupler chip U4, a light-emitting diode LED1, and a resistor R9. The clock terminal of the D flip-flop U2 is connected to the zero-crossing signal, the D terminal of the D flip-flop U2 is connected to the input control circuit, the power supply terminal of the D flip-flop U2 is connected to the power supply VDD, the GND terminal of the D flip-flop U2 is grounded, the output terminal of the D flip-flop U2 is connected to the anode of the input terminal of the optocoupler chip U3, the cathode of the input terminal of the optocoupler chip U3 is connected to the anode of the input terminal of the optocoupler chip U4, and the cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9; the collector of the output terminal of the optocoupler chip U3 is connected to the drive power supply signal V G -1 output by the first gate drive power supply circuit, and the emitter of the output terminal of the optocoupler chip U3 outputs a signal G-CTRL1 and is connected to the gate of the first MOSFET circuit; the collector of the output terminal of the optocoupler chip U4 is connected to the drive power supply signal V G -2 output by the second gate drive power supply circuit, and the emitter of the output terminal of the optocoupler chip U4 outputs a signal G-CTRL2 and is connected to the gate of the second MOSFET circuit.

[0017] In some of these embodiments, the polyphase AC power supply path includes a first-phase power supply path, a second-phase power supply path, and a third-phase power supply path. The zero-crossing detection circuit includes resistors R4, R5, R10 to R13, a bidirectional optocoupler chip U1, and a bidirectional optocoupler chip U7. One end of the resistor R4 is connected to the input end of the first-phase power supply path, the other end of the resistor R4 is connected to the first end of the bidirectional optocoupler chip U1, the second end of the bidirectional optocoupler chip U1 is connected to the input end of the second-phase power supply path, the third end of the bidirectional optocoupler chip U1 is connected to the power supply VDD, the fourth end of the bidirectional optocoupler chip U1 outputs a zero-crossing signal TRIG-1 and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded;

[0018] One end of the resistor R10 is connected to the input end of the third-phase power supply path, and the other end of the resistor R10 is connected to the first end of the bidirectional optocoupler chip U7. The second end of the bidirectional optocoupler chip U7 is connected to the input end of the first-phase power supply path through the resistor R11 and is also connected to the input end of the second-phase power supply path through the resistor R12. The third end of the bidirectional optocoupler chip U7 is connected to the power supply VDD. The fourth end of the bidirectional optocoupler chip U7 outputs a zero-crossing signal TRIG-2 and is connected to one end of the resistor R13, and the other end of the resistor R13 is grounded. The resistors R10, R11, and R12 have the same resistance value.

[0019] In some embodiments, the polyphase AC power supply control circuit includes a first MOSFET circuit, a second MOSFET circuit, a third MOSFET circuit, a first gate drive power supply circuit, a second gate drive power supply circuit, and a third gate drive power supply circuit.

[0020] The first MOSFET circuit is serially connected between the input end and the output end of the first-phase power supply path, and the ground of the first gate drive power supply circuit is connected to the source electrode of the first MOSFET circuit. The second MOSFET circuit is serially connected between the input end and the output end of the second-phase power supply path, and the ground of the second gate drive power supply circuit is connected to the source electrode of the second MOSFET circuit. The third MOSFET circuit is serially connected between the input end and the output end of the third-phase power supply path, and the ground of the third gate drive power supply circuit is connected to the source electrode of the third MOSFET circuit.

[0021] The MOSFET drive circuit includes D flip-flops U2 and U5, optocoupler chips U3, U4, and U6, light-emitting diodes LED1 and LED2, resistor R9, and resistor R14. The clock terminal of the D flip-flop U2 receives the zero-crossing signal TRIG-1. The D terminal of the D flip-flop U2 is connected to the input control circuit. The power supply terminal of the D flip-flop U2 is connected to the power supply VDD. The GND terminal of the D flip-flop U2 is grounded. The output terminal of the D flip-flop U2 is connected to the D terminal of the D flip-flop U5 and the anode of the input terminal of the optocoupler chip U3. The cathode of the input terminal of the optocoupler chip U3 is connected to the anode of the input terminal of the optocoupler chip U4. The cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9. The collector of the output terminal of the optocoupler chip U3 receives the drive power supply signal V output by the first gate drive power supply circuit. G-1. The emitter of the output terminal of the optocoupler chip U3 outputs a signal G-CTRL1, which is connected to the gate of the first MOSFET circuit; the collector of the output terminal of the optocoupler chip U4 is connected to the drive power signal V output by the second gate drive power circuit. G -2. The emitter of the output terminal of the optocoupler chip U4 outputs a signal G-CTRL2, which is connected to the gate of the second MOSFET circuit.

[0022] The clock terminal of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2, the power terminal of the D flip-flop U5 is connected to the power supply VDD, the GND terminal of the D flip-flop U5 is grounded, the output terminal of the D flip-flop U5 is connected to the anode of the input terminal of the optocoupler chip U6, the cathode of the input terminal of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14, and the collector of the output terminal of the optocoupler chip U6 is connected to the drive power signal V output by the third gate drive power circuit. G -3. The emitter of the output terminal of the optocoupler chip U6 outputs a signal G-CTRL3, which is connected to the gate of the third MOSFET circuit.

[0023] In some of the embodiments, the multiphase AC power supply control circuit includes a second MOSFET circuit, a third MOSFET circuit, a second gate drive power circuit, and a third gate drive power circuit.

[0024] The second MOSFET circuit is connected in series between the input terminal and the output terminal of the second-phase power supply path, and the ground of the second gate drive power circuit is connected to the source of the second MOSFET circuit; the third MOSFET circuit is connected in series between the input terminal and the output terminal of the third-phase power supply path, and the ground of the third gate drive power circuit is connected to the source of the third MOSFET circuit; the input terminal and the output terminal of the first-phase power supply path are directly connected.

[0025] The MOSFET drive circuit includes a D flip-flop U2, a D flip-flop U5, an optocoupler chip U4, an optocoupler chip U6, a light-emitting diode LED1, a light-emitting diode LED2, a resistor R9, and a resistor R14. The clock terminal of the D flip-flop U2 is connected to the zero-crossing signal TRIG-1, the D terminal of the D flip-flop U2 is connected to the input control circuit, the power terminal of the D flip-flop U2 is connected to the power supply VDD, the GND terminal of the D flip-flop U2 is grounded, the output terminal of the D flip-flop U2 is connected to the D terminal of the D flip-flop U5 and the anode of the input terminal of the optocoupler chip U4, and the cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9; the collector of the output terminal of the optocoupler chip U4 is connected to the drive power signal V output by the second gate drive power circuit.G -2, the emitter of the output terminal of the optocoupler chip U4 outputs a signal G-CTRL2, which is connected to the gate of the second MOSFET circuit;

[0026] The clock terminal of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2. The power supply terminal of the D flip-flop U5 is connected to the power supply VDD. The GND terminal of the D flip-flop U5 is grounded. The output terminal of the D flip-flop U5 is connected to the anode of the input terminal of the optocoupler chip U6. The cathode of the input terminal of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14. The collector of the output terminal of the optocoupler chip U6 is connected to the drive power signal V G -3 output by the third gate drive power circuit, and the emitter of the output terminal of the optocoupler chip U6 outputs a signal G-CTRL3, which is connected to the gate of the third MOSFET circuit.

[0027] In a second aspect, a solid-state relay is provided in this embodiment. The solid-state relay includes the polyphase AC power supply control circuit described in the first aspect.

[0028] Compared with the related art, in the polyphase AC power supply control circuit provided in this embodiment, the zero-crossing detection circuit outputs a zero-crossing signal when the polyphase alternating current output by the polyphase AC power supply path passes through the zero-crossing point. Under the trigger of the zero-crossing signal, the MOSFET drive circuit controls the gate drive power circuit to provide a drive power signal to the corresponding MOSFET circuit based on the enable signal sent by the input control circuit; the MOSFET circuit controls the corresponding AC power supply path to conduct based on the drive power signal, that is, by detecting the zero-crossing moment of the alternating current, controlling the corresponding AC power supply path to conduct or disconnect at the zero-crossing point, suppressing the inrush current during the on-off process, solving the problem that the inrush current during the circuit on-off process is too large and is not conducive to the long-term use of the MOSFET, and effectively protecting the MOSFET device and the load.

[0029] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more concise and understandable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0031] Figure 1 is a connection schematic diagram of a polyphase AC power supply control circuit of some embodiments of the present application;

[0032] Figure 2It is a schematic diagram of the MOSFET circuit of some embodiments of the present application;

[0033] Figure 3 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the two-phase (L1, L2) AC power supply control circuit of the first embodiment of the present application;

[0034] Figure 4 It is a schematic diagram of the first zero-crossing detection circuit of the first embodiment of the present application;

[0035] Figure 5 It is a schematic diagram of the input control circuit and the first MOSFET drive circuit of the first embodiment of the present application;

[0036] Figure 6 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the two-phase (L1, L2) AC power supply control circuit of the second embodiment of the present application;

[0037] Figure 7 It is a schematic diagram of the input control circuit and the second MOSFET drive circuit of the second embodiment of the present application;

[0038] Figure 8 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the three-phase (L1, L2, L3) AC power supply control circuit of the third embodiment of the present application;

[0039] Figure 9 It is a schematic diagram of the second zero-crossing detection circuit of the third embodiment of the present application;

[0040] Figure 10 It is a schematic diagram of the input control circuit and the third MOSFET drive circuit of the third embodiment of the present application;

[0041] Figure 11 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the three-phase (L1, L2, L3) AC power supply control circuit of the fourth embodiment of the present application;

[0042] Figure 12 It is a schematic diagram of the input control circuit and the fourth MOSFET drive circuit of the fourth embodiment of the present application. Detailed implementation manners

[0043] To understand the purpose, technical solution and advantages of the present application more clearly, the present application will be described and illustrated below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0044] Unless otherwise defined, technical terms or scientific terms involved in this application shall have the ordinary meanings understood by those with ordinary skills in the technical field to which this application belongs. In this application, words such as "a", "an", "one kind", "the", "these", etc. do not indicate a limitation in quantity, and they can be singular or plural. The terms "including", "containing", "having" and any variants thereof involved in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or device containing a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent in these processes, methods, products or devices. The terms "connected", "linked", "coupled", etc. involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether directly connected or indirectly connected. The term "plurality" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Usually, the character " / " indicates that the objects associated before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific order for the objects.

[0045] Figure 1 is a connection schematic diagram of a polyphase AC power supply control circuit for some embodiments of this application. As Figure 1 shown, the polyphase AC power supply control circuit includes at least one MOSFET circuit 11 and at least one gate drive power supply circuit 14 connected corresponding to the MOSFET circuit. The MOSFET circuit 11 is connected in series in any one-phase AC power supply path ( Figure 1 shows 2 AC power supply paths, as well as 2 MOSFET circuits and corresponding 2 gate drive power supply circuits); the polyphase AC power supply control circuit further includes an input control circuit 17, a MOSFET drive circuit 16 and a zero-crossing detection circuit 15. The zero-crossing detection circuit 15 is connected to the input terminals L1~LN of the polyphase AC power supply path. Those skilled in the art can understand that Figure 1 the structure shown is only schematic and does not limit the structure of the above polyphase AC power supply control circuit. For example, the polyphase AC power supply control circuit may further include Figure 1 more AC phases than shown, as well as more or fewer MOSFET circuits 11 and gate drive power supply circuits 14.

[0046] The zero-crossing detection circuit 15 outputs a zero-crossing signal when the polyphase alternating current output by the polyphase AC power supply path passes through the zero point; the MOSFET driving circuit 16, triggered by the zero-crossing signal and based on the enable signal sent by the input control circuit 17, controls the gate driving power supply circuit 14 to provide a driving power signal to the corresponding MOSFET circuit 11; the MOSFET circuit 11 controls the conduction of the corresponding AC power supply path based on the driving power signal.

[0047] The polyphase AC power supply control circuit of this embodiment may include a two-phase (L1, L2) AC power supply control circuit and a three-phase (L1, L2, L3) AC power supply control circuit. The number of the MOSFET circuits 11 and the gate driving power supply circuits 14 may be less than or equal to the number of phases of the alternating current. Specifically, when the alternating current is two-phase, the number of the MOSFET circuits 11 and the gate driving power supply circuits 14 may be 1 or 2; when the alternating current is three-phase, the number of the MOSFET circuits 11 and the gate driving power supply circuits 14 may be 2 or 3. The MOSFET circuit 11 may be connected in series between the input ends L1~LN and the corresponding output ends O1~ON of any phase of the AC power supply path.

[0048] The zero-crossing detection circuit 15 is connected to the input ends L1~LN of each phase of the AC power supply path, detects whether the polyphase alternating current passes through the zero point according to the voltage of each phase of the alternating current, and outputs a zero-crossing signal when passing through the zero point. The input control circuit 17 can convert the externally input control signal into an enable signal matching the voltage level of the subsequent circuit and form a certain signal isolation. The control signal is in an effective state at a low level and an invalid state at a high level; the enable signal is in an invalid state at a low level and an effective state at a high level.

[0049] When the enable signal changes from invalid to valid, the MOSFET driving circuit 16, triggered by the zero-crossing signal, controls the gate driving power supply circuit 14 to provide a driving power signal to the corresponding MOSFET circuit 11, and this driving power signal is used to control the conduction of the corresponding AC power supply path; when the enable signal changes from valid to invalid, the MOSFET driving circuit 16, triggered by the zero-crossing signal, controls the gate driving power supply circuit 14 to stop providing a driving power signal to the corresponding MOSFET circuit 11, and the corresponding AC power supply path is disconnected.

[0050] The polyphase AC power supply control circuit provided by this embodiment, by detecting the zero-crossing moment of the alternating current and controlling the conduction or disconnection of the corresponding AC power supply path at the zero-crossing point, suppresses the inrush current during the on-off process, solves the problem that the inrush current during the circuit on-off process is too large and is not conducive to the long-term use of the MOSFET, and effectively protects the MOSFET device and the load.

[0051] In some embodiments, the MOSFET drive circuit 16 includes a flip-flop, which outputs a turn-on / off control signal corresponding to the enable signal when receiving a zero-crossing signal, and the turn-on / off control signal is used to turn on or off the connection between the gate drive power supply circuit 14 and the corresponding MOSFET circuit 11.

[0052] The flip-flop in this embodiment may be a D flip-flop. The D flip-flop includes a clock terminal, a D input terminal, and a Q output terminal. The clock terminal is connected to the zero-crossing signal, the D input terminal is connected to the enable signal, and the Q output terminal outputs the turn-on / off control signal. When the enable signal connected to the D input terminal is at a high level, in the case of receiving a zero-crossing signal, the high-level signal at the D input terminal is output to the Q output terminal, and the turn-on / off control signal is at a high level. This high-level turn-on / off control signal is used to control the connection between the gate drive power supply circuit 14 and the corresponding MOSFET circuit 11 to conduct, provide a drive power signal, and turn on the corresponding AC power supply path.

[0053] When the enable signal connected to the D input terminal is at a low level, in the case of receiving a zero-crossing signal, the low-level signal at the D input terminal is output to the Q output terminal, and the turn-on / off control signal is at a low level. This low-level turn-on / off control signal is used to control the disconnection of the connection between the gate drive power supply circuit 14 and the corresponding MOSFET circuit 11. The gate drive power supply circuit 14 stops providing a drive power signal to the corresponding MOSFET circuit 11, and the corresponding AC power supply path is disconnected.

[0054] In some embodiments, the gate drive power supply circuit 14 outputs a drive power signal through transformer isolation, and the ground of the gate drive power supply circuit 14 is connected to the source of the MOSFET in the corresponding MOSFET circuit 11.

[0055] The gate drive power supply circuit 14 is used to provide a gate drive voltage to the corresponding MOSFET circuit 11. Since the field effect transistor is controlled to turn on and off by the voltage between the source and the gate, and the source in the MOSFET circuit 11 is in a floating state, an independent power supply is required. The gate drive power supply circuit 14 can be set to generate a drive power signal after transformer isolation. Connecting the ground of the gate drive power supply circuit 14 to the source of the MOSFET in the MOSFET circuit 11 can apply the drive power signal output by the gate drive power supply circuit 14 to the gate of the MOSFET in the corresponding MOSFET circuit 11 to achieve turn-on control.

[0056] Specifically, Figure 2 is a schematic diagram of the MOSFET circuit according to some embodiments of the present application. As Figure 2As shown, the MOSFET circuit 11 includes two back-to-back connected MOSFET devices T1 and MOSFET device T2, as well as capacitor C1, resistor R2, resistor R3, and varistor R1. The source S of T1 and the source S of T2 are connected, the gate G of T1 and the gate G of T2 are connected, and a resistor R3 is connected between the source S and the gate G; capacitor C1 is connected in series with resistor R2 and then connected between the drain D of T1 and the drain D of T2, and is connected in parallel with varistor R1; the drain D of T1 is connected to the input end of the MOSFET circuit 11, and the drain D of T2 is connected to the output end of the MOSFET circuit 11.

[0057] Semiconductor devices make no sound when conducting and disconnecting, and are voltage-driven, so they have the advantages of low noise and low power consumption. To achieve two-way conduction and disconnection control, the source S of T1 and the source S of T2 are connected, and the common terminal after connection is used as the source of the MOSFET circuit 11. The gate G of T1 and the gate G of T2 are connected, and at the same time, a resistor R3 is connected between the gate G and the source S. To protect T1 and T2, safety capacitor C1 is connected in series with resistor R2 and then connected in parallel between the drain D of T1 and the drain D of T2, and at the same time, varistor R1 is connected in parallel between the drain D of T1 and the drain D of T2. The drain D of T1 is connected to the input end of the MOSFET circuit 11, and the drain D of T2 is connected to the output end of the MOSFET circuit 11.

[0058] Embodiment 1:

[0059] Figure 3 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the two-phase (L1, L2) AC power supply control circuit of the first embodiment of the present application. As Figure 3 shown, the multi-phase AC power supply control circuit of this embodiment includes a first MOSFET circuit 1 and a first gate drive power supply circuit 4. The multi-phase AC power supply path includes a first-phase power supply path and a second-phase power supply path. The first MOSFET circuit 1 is connected in series between the input end L1 and the output end O1 of the first-phase power supply path. The ground Gs-1 of the first gate drive power supply circuit 4 is connected to the source S of the first MOSFET circuit 1, and the input end L2 of the second-phase power supply path is directly connected to the output end O2.

[0060] The multi-phase AC power supply control circuit of this embodiment further includes an input control circuit 7, a first MOSFET drive circuit, and a first zero-crossing detection circuit. Figure 4 It is a schematic diagram of the first zero-crossing detection circuit of the first embodiment of the present application. As Figure 4As shown in the figure, the first zero-crossing detection circuit includes a resistor R4, a resistor R5, and a bilateral optocoupler chip U1. One end of the resistor R4 is connected to the input terminal L1 of the first-phase power supply path, the other end of the resistor R4 is connected to the first terminal of the bilateral optocoupler chip U1, the second terminal of the bilateral optocoupler chip U1 is connected to the input terminal L2 of the second-phase power supply path, the third terminal of the bilateral optocoupler chip U1 is connected to the power supply VDD, the fourth terminal of the bilateral optocoupler chip U1 outputs a zero-crossing signal TRIG-1 and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded.

[0061] The first zero-crossing detection circuit is used to detect the voltage zero-crossing. Every time a zero-crossing occurs between L1 and L2, a zero-crossing signal TRIG-1 will be output.

[0062] Figure 5 It is the schematic diagram of the input control circuit and the first MOSFET drive circuit in the first embodiment of the present application. As Figure 5 shown, the first MOSFET drive circuit includes a D flip-flop U2, an optocoupler chip U3, a light-emitting diode LED1, and a resistor R9. The clock terminal CLK of the D flip-flop U2 is connected to the zero-crossing signal TRIG-1, the D input terminal of the D flip-flop U2 is connected to the input control circuit 7, the power supply terminal VCC of the D flip-flop U2 is connected to the power supply VDD, the GND terminal of the D flip-flop U2 is grounded, the Q output terminal of the D flip-flop U2 is connected to the anode of the input terminal of the optocoupler chip U3, the cathode of the input terminal of the optocoupler chip U3 is grounded through the light-emitting diode LED1 and the resistor R9, and the collector of the output terminal of the optocoupler chip U3 is connected to the drive power signal V G -1 output by the first gate drive power circuit 4, and the emitter of the output terminal of the optocoupler chip U3 outputs a signal G-CTRL1 and is connected to the gate S of the first MOSFET circuit 1.

[0063] As Figure 5 shown, the input control circuit 7 includes a resistor R6, a resistor R7, a resistor R8, and a triode Q1. The triode Q1 is a PNP triode. The external control signal CTRL is connected to the base of the triode Q1 through the resistor R7. The emitter of the triode Q1 is connected to the power supply VDD. The resistor R6 is connected in parallel between the base and the emitter of the triode Q1. The collector of the triode Q1 is connected to the resistor R8, and the other end of the resistor R8 is grounded.

[0064] The input control circuit 7 is used to convert the external control signal CTRL into the voltage level required by the subsequent circuit and form a certain signal isolation; when the external control signal CTRL is at a low level, the PNP transistor Q1 conducts, and the collector outputs a high level. When the external control signal CTRL is valid (low level), the D input terminal of the D flip-flop U2 is at a high level, but it still needs to wait for the zero-crossing signal TRIG-1 to provide a transition signal, and the Q output terminal of the D flip-flop U2 can become valid, output the high level at the D terminal to the Q output terminal, and turn on the optocoupler chip U3, and output V G -1 is applied to the gate of the first MOSFET circuit 1 through the emitter to control the conduction of the AC power supply path, and at the same time, the light-emitting diode LED1 provides a visual display of the conduction state.

[0065] When the external control signal CTRL changes from valid to invalid (high level or high impedance state), it also needs to be triggered by the zero-crossing signal TRIG-1 to cut off the optocoupler chip U3, disconnect the connection between the first gate drive power supply circuit 4 and the first MOSFET circuit 1, and control the disconnection of the AC power supply path.

[0066] In this embodiment, the input end L1 of the first-phase power supply path is connected to the output end O1 through the first MOSFET circuit 1, and the input end L2 of the second-phase power supply path is directly connected to the output end O2, so as to realize the working control of the load.

[0067] Embodiment 2:

[0068] Figure 6 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the two-phase (L1, L2) AC power supply control circuit of the second embodiment of the present application. As Figure 6 shown, the multi-phase AC power supply control circuit of this embodiment includes a first MOSFET circuit 1, a second MOSFET circuit 2, a first gate drive power supply circuit 4, and a second gate drive power supply circuit 5. The multi-phase AC power supply path includes a first-phase power supply path and a second-phase power supply path. The first MOSFET circuit 1 is connected in series between the input end L1 and the output end O1 of the first-phase power supply path, and the ground Gs-1 of the first gate drive power supply circuit 4 is connected to the source S of the first MOSFET circuit 1; the second MOSFET circuit 2 is connected in series between the input end L2 and the output end O2 of the second-phase power supply path, and the ground Gs-2 of the second gate drive power supply circuit 5 is connected to the source S of the second MOSFET circuit 2.

[0069] The multiphase AC power supply control circuit of this embodiment further includes an input control circuit, a second MOSFET drive circuit, and a first zero-crossing detection circuit. The first zero-crossing detection circuit is the same as the first zero-crossing detection circuit in Embodiment 1. Every time a zero-crossing occurs between L1 and L2, the emitter of the bidirectional optocoupler chip U1 will output a zero-crossing signal TRIG-1. The input control circuit is the same as the input control circuit 7 in Embodiment 1.

[0070] Figure 7 It is the schematic diagram of the input control circuit and the second MOSFET drive circuit in Embodiment 2 of this application. As Figure 7 shown, the second MOSFET drive circuit includes a D flip-flop U2, an optocoupler chip U3, an optocoupler chip U4, a light-emitting diode LED1, and a resistor R9. The clock terminal CLK of the D flip-flop U2 is connected to the zero-crossing signal TRIG-1. The D input terminal of the D flip-flop U2 is connected to the input control circuit. The power supply terminal VCC of the D flip-flop U2 is connected to the power supply VDD. The GND terminal of the D flip-flop U2 is grounded. The Q output terminal of the D flip-flop U2 is connected to the anode of the input terminal of the optocoupler chip U3. The cathode of the input terminal of the optocoupler chip U3 is connected to the anode of the input terminal of the optocoupler chip U4. The cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9; the collector of the output terminal of the optocoupler chip U3 is connected to the drive power signal V G -1 output by the first gate drive power supply circuit 4. The emitter of the output terminal of the optocoupler chip U3 outputs a signal G-CTRL1, which is connected to the gate of the first MOSFET circuit 1; the collector of the output terminal of the optocoupler chip U4 is connected to the drive power signal V G -2 output by the second gate drive power supply circuit 5. The emitter of the output terminal of the optocoupler chip U4 outputs a signal G-CTRL2, which is connected to the gate of the second MOSFET circuit 2.

[0071] The first MOSFET circuit 1 and the first gate drive power supply circuit 4 in this embodiment are respectively the same as the first MOSFET circuit 1 and the first gate drive power supply circuit 4 in Embodiment 1. The second MOSFET circuit 2 in this embodiment is the same as the first MOSFET circuit 1, and the second gate drive power supply circuit 5 is the same as the first gate drive power supply circuit 4.

[0072] When the control signal CTRL is valid (low level), the D input terminal of the D flip-flop U2 is at a high level. When a jump signal is provided by the zero-crossing signal TRIG-1, the Q output terminal of the D flip-flop U2 becomes valid, and the high level at the D input terminal is output to the Q output terminal of the D flip-flop U2, turning on the optocoupler chips U3 and U4. At this time, the output V G -1 of the first gate drive power supply circuit 4 is applied to the gate of the first MOSFET circuit 1 through the emitter of the output of the optocoupler chip U3, and the output VG -2 is applied to the gate of the second MOSFET circuit 2 through the output emitter of the optocoupler chip U4 to control the conduction of the corresponding AC power supply path. At the same time, the light-emitting diode LED1 provides a visual display of the conduction state.

[0073] In the case where the control signal CTRL changes from valid to invalid (high level or high impedance state), the zero-crossing signal TRIG-1 is also required for triggering to cut off the optocoupler chips U3 and U4. The first gate drive power supply circuit 4 and the second gate drive power supply circuit 5 stop providing the drive power for the MOSFET, resulting in the disconnection of the corresponding AC power supply path.

[0074] In this embodiment, the input end L1 of the first-phase power supply path is connected to the output end O1 through the first MOSFET circuit 1, and the input end L2 of the second-phase power supply path is connected to the output end O2 through the second MOSFET circuit 2, which can achieve comprehensive control of the output ends O1 and O2 and improve the safety of AC power supply.

[0075] Embodiment Three:

[0076] Figure 8 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the three-phase (L1, L2, L3) AC power supply control circuit of the third embodiment of the present application. As Figure 8 shown, the multi-phase AC power supply control circuit of this embodiment includes a first MOSFET circuit 1, a second MOSFET circuit 2, a third MOSFET circuit 3, a first gate drive power supply circuit 4, a second gate drive power supply circuit 5, and a third gate drive power supply circuit 6. The multi-phase AC power supply path includes a first-phase power supply path, a second-phase power supply path, and a third-phase power supply path.

[0077] Among them, the first MOSFET circuit 1 is connected in series between the input end L1 and the output end O1 of the first-phase power supply path, and the ground Gs-1 of the first gate drive power supply circuit 4 is connected to the source S of the first MOSFET circuit 1; the second MOSFET circuit 2 is connected in series between the input end L2 and the output end O2 of the second-phase power supply path, and the ground Gs-2 of the second gate drive power supply circuit 5 is connected to the source S of the second MOSFET circuit 2; the third MOSFET circuit 3 is connected in series between the input end L3 and the output end O3 of the third-phase power supply path, and the ground Gs-3 of the third gate drive power supply circuit 6 is connected to the source S of the third MOSFET circuit 3.

[0078] In this embodiment, the first MOSFET circuit 1, the second MOSFET circuit 2, and the third MOSFET circuit 3 are all the same as the first MOSFET circuit 1 in the first embodiment, and the first gate drive power supply circuit 4, the second gate drive power supply circuit 5, and the second gate drive power supply circuit 6 are all the same as the first gate drive power supply circuit 4 in the first embodiment.

[0079] The multiphase AC power supply control circuit of this embodiment further includes an input control circuit, a third MOSFET drive circuit, and a second zero-crossing detection circuit. The input control circuit is the same as the input control circuit 7 in the first embodiment.

[0080] Figure 9 It is the schematic diagram of the second zero-crossing detection circuit in the third embodiment of this application. As Figure 9 shown, the second zero-crossing detection circuit includes a resistor R4, a resistor R5, resistors R10 to R13, a bidirectional optocoupler chip U1, and a bidirectional optocoupler chip U7. One end of the resistor R4 is connected to the input terminal L1 of the first-phase power supply path, the other end of the resistor R4 is connected to the first terminal of the bidirectional optocoupler chip U1, the second terminal of the bidirectional optocoupler chip U1 is connected to the input terminal L2 of the second-phase power supply path, the third terminal of the bidirectional optocoupler chip U1 is connected to the power supply VDD, the fourth terminal of the bidirectional optocoupler chip U1 outputs a zero-crossing signal TRIG-1 and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded. The zero-crossing signal TRIG-1 is the zero-crossing signal between the first-phase power supply path and the second-phase power supply path.

[0081] One end of the resistor R10 is connected to the input terminal L3 of the third-phase power supply path, the other end of the resistor R10 is connected to the first terminal of the bidirectional optocoupler chip U7, the second terminal of the bidirectional optocoupler chip U7 is connected to the input terminal L1 of the first-phase power supply path through the resistor R11 and is also connected to the input terminal L2 of the second-phase power supply path through the resistor R12; the third terminal of the bidirectional optocoupler chip U7 is connected to the power supply VDD, the fourth terminal of the bidirectional optocoupler chip U7 outputs a zero-crossing signal TRIG-2 and is connected to one end of the resistor R13, and the other end of the resistor R13 is grounded; where the resistance values of the resistor R10, the resistor R11, and the resistor R12 are the same. The zero-crossing signal TRIG-2 is the zero-crossing signal between L3 and L1, L2.

[0082] Figure 10 It is the schematic diagram of the input control circuit and the third MOSFET drive circuit in the third embodiment of this application. As Figure 10 shown, the third MOSFET drive circuit includes D flip-flops U2, D flip-flops U5, optocoupler chips U3, optocoupler chips U4, optocoupler chips U6, light-emitting diodes LED1, light-emitting diodes LED2, a resistor R9, and a resistor R14.

[0083] The clock terminal CLK of the D flip-flop U2 is connected to the zero-crossing signal TRIG-1. The D input terminal of the D flip-flop U2 is connected to the input control circuit. The power supply terminal VCC of the D flip-flop U2 is connected to the power supply VDD. The GND terminal of the D flip-flop U2 is grounded. The Q output terminal of the D flip-flop U2 is connected to the D input terminal of the D flip-flop U5 and the anode of the input terminal of the optocoupler chip U3. The cathode of the input terminal of the optocoupler chip U3 is connected to the anode of the input terminal of the optocoupler chip U4. The cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9.

[0084] The collector of the output terminal of the optocoupler chip U3 is connected to the drive power signal V G -1 output by the first gate drive power supply circuit 4. The emitter of the output terminal of the optocoupler chip U3 outputs the signal G-CTRL1 and is connected to the gate S of the first MOSFET circuit 1. The collector of the output terminal of the optocoupler chip U4 is connected to the drive power signal V G -2 output by the second gate drive power supply circuit 5. The emitter of the output terminal of the optocoupler chip U4 outputs the signal G-CTRL2 and is connected to the gate S of the second MOSFET circuit 2.

[0085] The clock terminal CLK of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2. The power supply terminal VCC of the D flip-flop U5 is connected to the power supply VDD. The GND terminal of the D flip-flop U5 is grounded. The Q output terminal of the D flip-flop U5 is connected to the anode of the input terminal of the optocoupler chip U6. The cathode of the input terminal of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14. The collector of the output terminal of the optocoupler chip U6 is connected to the drive power signal V G -3 output by the third gate drive power supply circuit 6. The emitter of the output terminal of the optocoupler chip U6 outputs the signal G-CTRL3 and is connected to the gate S of the third MOSFET circuit 3.

[0086] When the control signal CTRL is valid (low level), the D input terminal of the D flip-flop U2 is at a high level. When a jump signal is provided by the zero-crossing signal TRIG-1, the Q output terminal of the D flip-flop U2 becomes valid, outputs the high level of the D input terminal to the Q output terminal, and turns on the optocoupler chips U3 and U4, applying the output V G -1 of the first gate drive power supply circuit 4 to the gate of the first MOSFET circuit 1 through the emitter of the optocoupler chip U3. At the same time, applying the output V G -2 of the second gate drive power supply circuit 5 to the gate of the second MOSFET circuit 2 through the emitter of the optocoupler chip U4, controlling the corresponding AC power supply path to turn on. At the same time, the light-emitting diode LED1 provides a visual display of the on state. At this time, the two-phase power supplies L1 and L2 are turned on, and the current impact at the moment of connection is small.

[0087] Next, when the zero-crossing signal TRIG-2 provides a jump signal, the high level at the D input of the D flip-flop U5 is output to the Q output, and the optocoupler chip U6 is turned on. The output V G -3 of the third gate drive power supply circuit 6 is applied to the gate of the third MOSFET circuit 3 through the emitter of the optocoupler chip U6 to control the conduction of the corresponding AC power supply path. At the same time, the light-emitting diode LED2 provides a visual display of the conduction state. At this time, the L3 power supply is turned on, and the current impact at the moment of connection is small.

[0088] When the control signal CTRL changes from valid to invalid (high level or high impedance state), the zero-crossing signals TRIG-1 and TRIG-2 are also required for triggering. The optocoupler chips U3, U4, and U6 are sequentially turned off, and the three-phase output terminals O1, O2, and O3 are powered off.

[0089] Embodiment 4:

[0090] Figure 11 It is a connection schematic diagram of the MOSFET circuit and the gate drive power supply circuit in the three-phase (L1, L2, L3) AC power supply control circuit of Embodiment 4 of the present application. As Figure 11 shown, the multi-phase AC power supply control circuit of this embodiment includes a second MOSFET circuit 2, a third MOSFET circuit 3, a second gate drive power supply circuit 5, and a third gate drive power supply circuit 6; the multi-phase AC power supply path includes a first-phase power supply path, a second-phase power supply path, and a third-phase power supply path.

[0091] Among them, the second MOSFET circuit 2 is connected in series between the input terminal L2 and the output terminal O2 of the second-phase power supply path, and the ground Gs-2 of the second gate drive power supply circuit 5 is connected to the source S of the second MOSFET circuit 2; the third MOSFET circuit 3 is connected in series between the input terminal L3 and the output terminal O3 of the third-phase power supply path, and the ground Gs-3 of the third gate drive power supply circuit 6 is connected to the source S of the third MOSFET circuit 3; the input terminal L1 of the first-phase power supply path is directly connected to the output terminal O1.

[0092] In this embodiment, the second MOSFET circuit 2 and the third MOSFET circuit 3 are both the same as the first MOSFET circuit 1 in Embodiment 1, and the second gate drive power supply circuit 5 and the second gate drive power supply circuit 6 are both the same as the first gate drive power supply circuit 4 in Embodiment 1.

[0093] The multi-phase AC power supply control circuit of this embodiment further includes an input control circuit, a fourth MOSFET drive circuit, and a second zero-crossing detection circuit. The second zero-crossing detection circuit is the same as the second zero-crossing detection circuit in Embodiment 3. The input control circuit is the same as the input control circuit 7 in Embodiment 1.

[0094] Figure 12 is the schematic diagram of the input control circuit and the fourth MOSFET drive circuit according to the fourth embodiment of the present application. As Figure 12 shown, the fourth MOSFET drive circuit includes a D flip-flop U2, a D flip-flop U5, an optocoupler chip U4, an optocoupler chip U6, a light-emitting diode LED1, a light-emitting diode LED2, a resistor R9, and a resistor R14.

[0095] The clock terminal CLK of the D flip-flop U2 is connected to the zero-crossing signal TRIG-1. The D input terminal of the D flip-flop U2 is connected to the input control circuit. The power supply terminal VCC of the D flip-flop U2 is connected to the power supply VDD. The GND terminal of the D flip-flop U2 is grounded. The Q output terminal of the D flip-flop U2 is connected to the D input terminal of the D flip-flop U5 and the anode of the input terminal of the optocoupler chip U4. The cathode of the input terminal of the optocoupler chip U4 is grounded through the light-emitting diode LED1 and the resistor R9. The collector of the output terminal of the optocoupler chip U4 is connected to the drive power signal V G -2 output by the second gate drive power supply circuit 5. The emitter of the output terminal of the optocoupler chip U4 outputs a signal G-CTRL2, which is connected to the gate S of the second MOSFET circuit 2.

[0096] The clock terminal CLK of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2. The power supply terminal VCC of the D flip-flop U5 is connected to the power supply VDD. The GND terminal of the D flip-flop U5 is grounded. The Q output terminal of the D flip-flop U5 is connected to the anode of the input terminal of the optocoupler chip U6. The cathode of the input terminal of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14. The collector of the output terminal of the optocoupler chip U6 is connected to the drive power signal V G -3 output by the third gate drive power supply circuit 6. The emitter of the output terminal of the optocoupler chip U6 outputs a signal G-CTRL3, which is connected to the gate S of the third MOSFET circuit 3.

[0097] When the control signal CTRL is valid (low level), the D terminal of the D flip-flop U2 is at a high level. When a jump signal is provided by the zero-crossing signal TRIG-1, the Q output terminal of the D flip-flop U2 becomes valid, outputs the high level at the D input terminal to the Q output terminal, and turns on the optocoupler chip U4, applying the output V G -2 of the second gate drive power supply circuit 5 to the gate of the second MOSFET circuit 2 through the emitter of the optocoupler chip U4 to control the conduction of the second-phase power supply path. At the same time, the light-emitting diode LED1 provides a visual display of the conduction state. At this time, the two-phase power supply of L1 and L2 is provided, and the current impact is small at the moment of connection.

[0098] Next, when the zero-crossing signal TRIG-2 provides a jump signal, the high level at the D input of the D flip-flop U5 is output to the Q output, and the optocoupler chip U6 is turned on, and the output V G -3 of the third gate drive power circuit 6 is applied to the gate of the third MOSFET circuit 3 through the emitter of the optocoupler chip U6 to control the conduction of the third-phase power supply path. At the same time, the light-emitting diode LED2 provides a visual display of the conduction state. At this time, the L3 power supply is turned on, and the current impact is small at the moment of connection.

[0099] When the control signal CTRL changes from valid to invalid (high level or high impedance state), the zero-crossing signals TRIG-1 and TRIG-2 are also required for triggering. The optocoupler chips U4 and U6 are sequentially turned off, and the power supply at the output terminals O2 and O3 is disconnected.

[0100] In this embodiment, the input terminal L1 of the first-phase power supply path is directly connected to the output terminal O1, while L2 is connected to the output terminal O2 through the second MOSFET circuit 2, and L3 is connected to the output terminal O3 through the third MOSFET circuit 3, so as to realize the operation control of the load.

[0101] Some embodiments of the present application also provide a solid-state relay, which includes the multi-phase AC power supply control circuit in the above embodiment.

[0102] The solid-state relay of this embodiment is applicable to two-phase and three-phase AC power supply circuits. By detecting the zero-crossing moment of the alternating current, the corresponding AC power supply path is controlled to be turned on or off at the zero-crossing point, suppressing the impact current during the on-off process, solving the problem that the impact current during the circuit on-off process is too large and is not conducive to the long-term use of the MOSFET, and effectively protecting the MOSFET device and the load.

[0103] It should be noted that the specific examples in this embodiment can refer to the examples described in the above embodiment and the optional implementation manners, and will not be repeated in this embodiment.

[0104] It should be understood that the specific embodiments described here are only used to explain this application, rather than to limit it. According to the embodiments provided by the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0105] Obviously, the accompanying drawings are only some examples or embodiments of the present application. For those of ordinary skill in the art, the present application can also be applied to other similar situations based on these drawings without creative efforts. Additionally, it can be understood that although the work done during this development process may be complex and time-consuming, for those of ordinary skill in the art, certain design, manufacturing, or production changes based on the technical content disclosed in the present application are only conventional technical means and should not be regarded as insufficient disclosure of the present application.

[0106] The term "embodiment" in the present application means that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears in various positions in the specification and does not necessarily mean the same embodiment, nor does it mean independence or alternative to other embodiments that are mutually exclusive. Those of ordinary skill in the art can clearly or implicitly understand that the embodiments described in the present application can be combined with other embodiments without conflict.

[0107] The above-described embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of patent protection. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A multi-phase AC power supply control circuit, characterized in that: The circuit includes at least one MOSFET circuit and at least one gate drive power supply circuit corresponding to the MOSFET circuit, wherein the MOSFET circuit is connected in series in any phase AC power supply path; the circuit also includes an input control circuit, a MOSFET drive circuit and a zero-crossing detection circuit, wherein the zero-crossing detection circuit is connected to the multi-phase AC power supply path; The zero-crossing detection circuit outputs a zero-crossing signal when the multi-phase AC power supply path outputs the multi-phase AC power supply path through the zero point; The MOSFET driving circuit, under the triggering of the zero-crossing signal, controls the gate driving power supply circuit to provide a driving power supply signal to the corresponding MOSFET circuit based on the enable signal sent by the input control circuit; The MOSFET driving circuit includes a trigger, and when receiving the zero-crossing signal, the trigger outputs an on-off control signal corresponding to the enable signal, and the on-off control signal is used to turn on or off the connection between the gate drive power supply circuit and the corresponding MOSFET circuit; The MOSFET circuit controls the corresponding AC power supply path to be turned on based on the driving power supply signal; Wherein, the multi-phase AC power supply path includes a first-phase power supply path and a second-phase power supply path, the zero-crossing detection circuit includes a resistor R4, a resistor R5 and a bidirectional optocoupler chip U1, one end of the resistor R4 is connected to the input end of the first-phase power supply path, the other end of the resistor R4 is connected to the first end of the bidirectional optocoupler chip U1, the second end of the bidirectional optocoupler chip U1 is connected to the input end of the second-phase power supply path, the third end of the bidirectional optocoupler chip U1 is connected to the power supply VDD, the fourth end of the bidirectional optocoupler chip U1 outputs the zero-crossing signal and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded; The multi-phase AC power supply control circuit also includes a first MOSFET circuit, a second MOSFET circuit, a first gate drive power circuit, and a second gate drive power circuit; the first MOSFET circuit is connected in series between the input end and the output end of the first phase power supply path, and the ground of the first gate drive power circuit is connected to the source of the first MOSFET circuit; the second MOSFET circuit is connected in series between the input end and the output end of the second phase power supply path, and the ground of the second gate drive power circuit is connected to the source of the second MOSFET circuit; the MOSFET drive circuit includes a D trigger U2, an optocoupler chip U3, and an optocoupler chip U4 , light emitting diode LED1 and resistor R9, the clock end of the D trigger U2 is connected to the zero-crossing signal, the D end of the D trigger U2 is connected to the input control circuit, the power end of the D trigger U2 is connected to the power supply VDD, the GND end of the D trigger U2 is grounded, the output end of the D trigger U2 is connected to the anode of the input end of the optocoupler chip U3, the cathode of the input end of the optocoupler chip U3 is connected to the anode of the input end of the optocoupler chip U4, and the cathode of the input end of the optocoupler chip U4 is grounded through the light emitting diode LED1 and the resistor R9; the collector of the output end of the optocoupler chip U3 is connected to the driving power signal V output by the first gate driving power circuit G -1, the output end emitter output signal G-CTRL1 of the optical coupling chip U3 is connected to the gate of the first MOSFET circuit; the output end collector of the optical coupling chip U4 is connected to the driving power supply signal V output by the second gate driving power supply circuit G -2, the output end emitter output signal G-CTRL2 of the optocoupler chip U4 is connected to the gate of the second MOSFET circuit.

2. The circuit according to claim 1, characterized in that The gate drive power circuit outputs the drive power signal through transformer isolation, and the ground of the gate drive power circuit is connected to the source of the MOSFET in the corresponding MOSFET circuit.

3. The multi-phase AC power supply control circuit according to any one of claims 1 to 2, characterized in that: The multi-phase AC power supply path may also include a first-phase power supply path, a second-phase power supply path, and a third-phase power supply path. The zero-crossing detection circuit includes a resistor R4, a resistor R5, resistors R10-R13, a bidirectional optocoupler chip U1, and a bidirectional optocoupler chip U7. One end of the resistor R4 is connected to the input end of the first-phase power supply path, the other end of the resistor R4 is connected to the first end of the bidirectional optocoupler chip U1, the second end of the bidirectional optocoupler chip U1 is connected to the input end of the second-phase power supply path, the third end of the bidirectional optocoupler chip U1 is connected to the power supply VDD, the fourth end of the bidirectional optocoupler chip U1 outputs a zero-crossing signal TRIG-1 and is connected to one end of the resistor R5, and the other end of the resistor R5 is grounded; One end of the resistor R10 is connected to the input end of the third-phase power supply path, the other end of the resistor R10 is connected to the first end of the bidirectional optocoupler chip U7, the second end of the bidirectional optocoupler chip U7 is connected to the input end of the first-phase power supply path through the resistor R11, and is connected to the input end of the second-phase power supply path through the resistor R12; the third end of the bidirectional optocoupler chip U7 is connected to the power supply VDD, the fourth end of the bidirectional optocoupler chip U7 outputs the zero-crossing signal TRIG-2 and is connected to one end of the resistor R13, and the other end of the resistor R13 is grounded; wherein the resistance values ​​of the resistor R10, the resistor R11 and the resistor R12 are the same.

4. The multi-phase AC power supply control circuit according to claim 3, characterized in that: The multi-phase AC power supply control circuit includes a first MOSFET circuit, a second MOSFET circuit, a third MOSFET circuit, a first gate drive power circuit, a second gate drive power circuit, and a third gate drive power circuit; The first MOSFET circuit is connected in series between the input end and the output end of the first phase power supply path, and the ground of the first gate drive power supply circuit is connected to the source of the first MOSFET circuit; the second MOSFET circuit is connected in series between the input end and the output end of the second phase power supply path, and the ground of the second gate drive power supply circuit is connected to the source of the second MOSFET circuit; the third MOSFET circuit is connected in series between the input end and the output end of the third phase power supply path, and the ground of the third gate drive power supply circuit is connected to the source of the third MOSFET circuit; The MOSFET driving circuit includes a D trigger U2, a D trigger U5, an optocoupler chip U3, an optocoupler chip U4, an optocoupler chip U6, a light emitting diode LED1, a light emitting diode LED2, a resistor R9, and a resistor R14. The clock end of the D trigger U2 is connected to the zero-crossing signal TRIG-1, the D end of the D trigger U2 is connected to the input control circuit, the power end of the D trigger U2 is connected to the power supply VDD, the GND end of the D trigger U2 is grounded, the output end of the D trigger U2 is connected to the D end of the D trigger U5 and the input anode of the optocoupler chip U3, the input cathode of the optocoupler chip U3 is connected to the input anode of the optocoupler chip U4, and the input cathode of the optocoupler chip U4 is grounded through the light emitting diode LED1 and the resistor R9; the output collector of the optocoupler chip U3 is connected to the driving power signal V output by the first gate driving power circuit G -1, the output end emitter output signal G-CTRL1 of the optical coupling chip U3 is connected to the gate of the first MOSFET circuit; the output end collector of the optical coupling chip U4 is connected to the driving power supply signal V output by the second gate driving power supply circuit G -2, the output end emitter output signal G-CTRL2 of the optical coupling chip U4 is connected to the gate of the second MOSFET circuit; The clock end of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2, the power end of the D flip-flop U5 is connected to the power supply VDD, the GND end of the D flip-flop U5 is grounded, the output end of the D flip-flop U5 is connected to the anode of the input end of the optocoupler chip U6, the cathode of the input end of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14, and the collector of the output end of the optocoupler chip U6 is connected to the driving power signal V output by the third gate driving power circuit. G -3, the output end emitter output signal G-CTRL3 of the optocoupler chip U6 is connected to the gate of the third MOSFET circuit.

5. The multi-phase AC power supply control circuit according to claim 3, characterized in that: The multi-phase AC power supply control circuit includes a second MOSFET circuit, a third MOSFET circuit, a second gate drive power supply circuit, and a third gate drive power supply circuit; The second MOSFET circuit is connected in series between the input end and the output end of the second phase power supply path, and the ground of the second gate drive power supply circuit is connected to the source of the second MOSFET circuit; the third MOSFET circuit is connected in series between the input end and the output end of the third phase power supply path, and the ground of the third gate drive power supply circuit is connected to the source of the third MOSFET circuit; the input end and the output end of the first phase power supply path are directly connected; The MOSFET driving circuit includes a D trigger U2, a D trigger U5, an optocoupler chip U4, an optocoupler chip U6, a light emitting diode LED1, a light emitting diode LED2, a resistor R9, and a resistor R14. The clock end of the D trigger U2 is connected to the zero-crossing signal TRIG-1, the D end of the D trigger U2 is connected to the input control circuit, the power end of the D trigger U2 is connected to the power supply VDD, the GND end of the D trigger U2 is grounded, the output end of the D trigger U2 is connected to the D end of the D trigger U5 and the anode of the input end of the optocoupler chip U4, and the cathode of the input end of the optocoupler chip U4 is grounded through the light emitting diode LED1 and the resistor R9; the collector of the output end of the optocoupler chip U4 is connected to the driving power signal V output by the second gate driving power circuit. G -2, the output end emitter output signal G-CTRL2 of the optical coupling chip U4 is connected to the gate of the second MOSFET circuit; The clock end of the D flip-flop U5 is connected to the zero-crossing signal TRIG-2, the power end of the D flip-flop U5 is connected to the power supply VDD, the GND end of the D flip-flop U5 is grounded, the output end of the D flip-flop U5 is connected to the anode of the input end of the optocoupler chip U6, the cathode of the input end of the optocoupler chip U6 is grounded through the light-emitting diode LED2 and the resistor R14, and the collector of the output end of the optocoupler chip U6 is connected to the driving power signal V output by the third gate driving power circuit. G -3, the output end emitter output signal G-CTRL3 of the optocoupler chip U6 is connected to the gate of the third MOSFET circuit.

6. A solid-state relay, characterized in that: The solid-state relay comprises a multi-phase AC power supply control circuit as described in any one of claims 1 to 5.

Images