Load-hold circuit and electronic device

Abstract

The application relates to a load self-locking circuit and an electronic device. The load self-locking circuit comprises a first switch, a first end of the first switch being connected to a power grid signal, a second end of the first switch being connected to a first end of a load; a control module being connected to a main control unit and the second end of the first switch, for detecting a zero-crossing point of the power grid signal when the first switch is closed to output a zero-crossing point control signal to the main control unit, and generating a control voltage when the first switch is closed; a self-locking module being connected to the control module and the main control unit, for starting based on a starting control signal of the main control unit and the control voltage at the zero-crossing point, and generating a self-locking control signal after starting, the starting control signal being sent when the main control unit receives the zero-crossing point control signal; and a grid-connected switch module, a control end and an output switch end of the grid-connected switch module being connected to an output end of the self-locking module and a second end of the load respectively, for self-locking based on the self-locking control signal at the zero-crossing point, so that the load is in a power-on state, and the load is prevented from being unexpectedly powered off.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a load self-locking circuit and electronic device. Background Technology

[0002] In various electrical control equipment, power supply stability and operational safety are the core prerequisites for ensuring reliable operation of the equipment.

[0003] Traditional technologies often lack effective mechanisms to prevent accidental power-off in the power supply circuits of equipment. This can lead to the switch controlling the power-on or power-off of the load being accidentally disconnected, resulting in unexpected power-off of the load, affecting the normal operation of the system, and even causing equipment failure or data loss.

[0004] Therefore, there is an urgent need for a circuit solution that can prevent accidental power failure in order to improve the stability and safety of equipment operation. Summary of the Invention

[0005] Therefore, it is necessary to provide a load self-locking circuit, including:

[0006] The first switch KEY1 has a first end for connecting to the power grid to receive the power grid signal, and a second end for connecting to the first end of the load RL.

[0007] Control module 100 is connected to the main control unit and the second terminal of the first switch KEY1. The control module 100 is used to detect the zero-crossing time of the power grid signal when the first switch KEY1 is closed, so as to output a zero-crossing control signal V_ZERO to the main control unit, and to generate a control voltage VCC when the first switch KEY1 is closed.

[0008] A self-locking module 200 is connected to the output terminal of the control module 100 and the main control unit. The self-locking module 200 is used to start based on the start control signal ZERO-K of the main control unit and the control voltage VCC at the zero crossing point, and to generate a self-locking control signal after starting. The start control signal ZERO-K is used to be issued when the main control unit receives the zero-point control signal V_ZERO.

[0009] A grid-connected switch module 300 is provided, wherein the control terminal and the output switch terminal of the grid-connected switch module 300 are respectively connected to the output terminal of the self-locking module 200 and the second terminal of the load RL. The grid-connected switch module 300 is used to self-lock based on the self-locking control signal at the zero-crossing point so that the load RL is in a energized state.

[0010] In one embodiment, the control module 100 includes:

[0011] Rectifier submodule 110, zero-crossing detection submodule 120 and voltage generation submodule 130;

[0012] The input terminal of the rectifier submodule 110 is connected to the power grid signal through the first switch KEY1. The output terminal of the rectifier submodule 110 is connected to the first input terminal of the zero-crossing detection submodule 120. The second input terminal of the zero-crossing detection submodule 120 is connected to the output terminal of the voltage generation submodule 130. The output terminal of the zero-crossing detection submodule 120 is connected to the main control unit. The input terminal of the voltage generation submodule 130 is connected to the output terminal of the rectifier module 110. The output terminal of the voltage generation submodule 130 is also connected to the self-locking module 200.

[0013] The rectifier submodule 110 is used to rectify the grid signal to obtain a rectified signal; the voltage generation submodule 130 is used to generate a control voltage VCC based on the rectified signal output by the rectifier submodule 110; the zero-crossing detection submodule 120 is used to detect the zero-crossing time based on the rectified signal and the control voltage VCC, and output the zero-crossing control signal V_ZERO to the main control unit. In one embodiment, the zero-crossing detection submodule 120 includes:

[0014] Zero-crossing voltage divider unit 121, the input terminal of which is connected to the output terminal of rectifier submodule 110;

[0015] Zero-crossing switching unit 122, the control terminal of the zero-crossing switching unit 122 is connected to the output terminal of the zero-crossing voltage divider unit 121, the input terminal of the zero-crossing switching unit 122 is connected to the output terminal of the voltage generation submodule 130, and the output terminal of the zero-crossing switching unit 122 is connected to the main control unit;

[0016] The zero-crossing voltage divider unit 121 is used to output a zero-crossing voltage divider signal to turn on the zero-crossing voltage divider unit 121 based on the rectified signal;

[0017] The zero-crossing switch unit 122 is used to output a low-level zero-point control signal V_ZERO to the main control unit when it is turned on.

[0018] In one embodiment, the voltage generation submodule 130 includes:

[0019] A power amplifier unit 131, the input terminal of which is connected to the output terminal of the rectifier submodule 110;

[0020] A voltage regulator output unit 132, the input terminal of which is connected to the output terminal of the power amplifier unit 131, and the output terminal of the voltage regulator output unit 132 is connected to the second input terminal of the self-locking module 200 and the zero-crossing detection submodule 120;

[0021] The regulated output unit 132 is used to output a control voltage VCC based on the power amplifier unit 131 being turned on.

[0022] In one embodiment, the self-locking module 200 includes:

[0023] Zero-point start submodule 210 is connected to the main control unit and the control module 100. The zero-point start submodule 210 is used to start based on the start control signal ZERO_K output by the main control unit.

[0024] A pulse signal generation submodule 220 is connected to the zero-point start submodule 210. The pulse signal generation submodule 220 is used to generate a pulse signal based on the control voltage VCC charging when the zero-point start submodule 210 is started.

[0025] The self-locking submodule 230 has its first and second input terminals connected to the output terminals of the pulse signal generation submodule 220 and the control module 100, respectively. The output terminal of the self-locking submodule 230 is connected to the control terminal of the grid-connected switch module 300. The self-locking submodule 230 is used to perform conduction self-locking based on the pulse signal and the control voltage VCC, so as to output a self-locking control signal for controlling the grid-connected switch module 300 to maintain closed locking.

[0026] In one embodiment, the zero-point start submodule 210 includes:

[0027] Switch Q8, the base of which is connected to the main control unit, the emitter of which is connected to the pulse signal generation submodule 220, and the collector of which is connected to the control module 100;

[0028] The switching transistor Q8 is used to turn on when the high-level start control signal ZERO_K is received.

[0029] In one embodiment, the pulse signal generation submodule 220 includes a switch Q7, a first oscillation unit 221, and a second oscillation unit 222; wherein the switch Q7 is a PNP type switch.

[0030] The emitter of the switching transistor Q7 is connected to the zero-point start-up submodule 210, the collector of the switching transistor Q7 is connected to the first oscillation unit 221, and the base of the switching transistor Q7 is connected to the second oscillation unit 222; the self-locking submodule 230 is connected to the second oscillation unit 222.

[0031] The switching transistor Q7 is used to turn on when the zero-point start-up submodule 210 is started; the first oscillation unit 221 and the second oscillation unit 222 are used to charge and store energy based on the control voltage VCC output by the control module 100 when the switching transistor Q7 is turned on, so as to output the pulse signal to the self-locking submodule 230.

[0032] In one embodiment, the self-locking submodule 230 includes a first switching unit 231 and a second switching unit 232;

[0033] The control terminal of the first switching unit 231 is connected to the pulse signal generation submodule 220, the control terminal of the second switching unit 232 is connected to the output terminal of the first switching unit 231 and the control module 100, and the output terminal of the second switching unit 232 is connected to the control terminal of the grid-connected switching module 300.

[0034] The first switching unit 231 and the second switching unit 232 maintain conduction lock based on the pulse signal and the control voltage VCC, and output a self-locking control signal for controlling the grid-connected switch module 300 to maintain closed lock.

[0035] In one embodiment, the circuit further includes:

[0036] The second switch KEY2 is connected to the control terminal of the first switch unit 231. The second switch KEY2 is used to control the first switch unit 231 to open when closed so that the self-locking submodule 230 can release the self-locking state, thereby controlling the grid-connected switch module 300 to open.

[0037] Secondly, this application also provides an electronic device including a load self-locking circuit according to any of the above embodiments.

[0038] The aforementioned load self-locking circuit includes a first switch, a control module, a self-locking module, and a grid-connected switch module. The control module, when the first switch is closed, works with the main control unit to detect the zero-crossing moment of the grid signal and generates a control voltage when the first switch is closed. The self-locking module starts at the zero-crossing moment based on the start control signal and control voltage from the main control unit and generates a self-locking control signal after startup. The grid-connected switch module performs self-locking based on the self-locking control signal at the zero-crossing moment, ensuring the load remains in a locked energized state. That is, if the power supply voltage to the grid-connected switch module is unexpectedly disconnected, the load switch (grid-connected switch module) remains locked, preventing accidental power loss and providing stability. Simultaneously, the grid-connected switch module conducts at the zero-crossing moment of the grid signal, effectively preventing arcing. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a block diagram of a load self-locking circuit in one embodiment;

[0041] Figure 2 This is a circuit diagram of a load self-locking circuit in one embodiment. Detailed Implementation

[0042] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0044] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0045] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0046] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0047] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0048] Combination Figure 1 and Figure 2 As shown, where Figure 1 This is a block diagram of a load self-locking circuit in one embodiment; Figure 2 This is a circuit diagram of a load self-locking circuit in one embodiment.

[0049] This application provides a load self-locking circuit, including a first switch KEY1, a control module 100, a self-locking module 200, and a grid-connected switch module 300.

[0050] The first terminal of the first switch KEY1 is used to connect to the power grid signal, and the second terminal of the first switch KEY1 is connected to the first terminal of the load RL; the control module 100 is connected to the main control unit and the second terminal of the first switch KEY1; the self-locking module 200 is connected to the control module 100 and the main control unit (not shown in the figure), and the control terminal and output switch terminal of the grid-connected switch module 300 are respectively connected to the output terminal of the self-locking module 200 and the second terminal of the load RL.

[0051] The control module 100 is used to detect the zero-crossing moment of the grid signal when the first switch KEY1 is closed to output a zero-crossing control signal V_ZERO from the main control unit, and to generate a control voltage VCC when the first switch KEY1 is closed. The self-locking module 200 is used to start based on the start control signal ZERO-K from the main control unit and the control voltage VCC at the zero-crossing moment, and to generate a self-locking control signal after startup. The start control signal ZERO-K is issued when the main control unit receives the zero-crossing control signal V_ZERO. The grid-connected switch module 300 is used to perform self-locking based on the self-locking control signal at the zero-crossing moment, so that the load RL is energized. The main control unit may include a processor, such as a CPU, etc., without specific limitations.

[0052] In the load self-locking circuit, the self-locking module 200 connects the control module 100 and the main control unit. The main control unit receives the zero-point control signal V_ZERO output by the control module 100 at the zero-crossing point. Upon receiving the zero-point control signal V_ZERO, the main control unit outputs a start control signal ZERO-K to the self-locking module 200. Thus, the self-locking module 200 generates a self-locking control signal based on the control voltage VCC at the zero-crossing point. This self-locking control signal is used to control the closing of the load RL switch. This ensures that even if the power supply voltage of the grid-connected switch module 300 is unexpectedly disconnected, the switch of the load RL (grid-connected switch module) remains locked, preventing accidental power loss and providing stability. Furthermore, the closing of the load RL switch at the zero-crossing point effectively prevents arcing.

[0053] The aforementioned load self-locking circuit includes a first switch KEY1, a control module 100, a self-locking module 200, and a grid-connected switch module 300. The control module 100, when the first switch KEY1 is closed, cooperates with the main control unit to detect the zero-crossing moment of the grid signal and generates a control voltage VCC when the first switch KEY1 is closed. The self-locking module 200 starts at the zero-crossing moment based on the start control signal ZERO-K from the main control unit and the control voltage VCC, and generates a self-locking control signal after startup. The grid-connected switch module 300 performs self-locking based on the self-locking control signal at the zero-crossing moment, ensuring that the load RL is energized. That is, if the power supply voltage of the grid-connected switch module 300 is unexpectedly disconnected, the switch (grid-connected switch module) of the load RL can remain locked, thus preventing the load RL from being unexpectedly powered down and providing stability. Simultaneously, the grid-connected switch module conducts at the zero-crossing moment of the grid signal, effectively preventing arcing.

[0054] In some alternative embodiments, refer to Figure 1 and Figure 2 The control module 100 includes a rectifier submodule 110, a zero-crossing detection submodule 120, and a voltage generation submodule 130.

[0055] Specifically, the input terminal of the rectifier submodule 110 is connected to the power grid signal through the first switch KEY1, the output terminal of the rectifier submodule 110 is connected to the first input terminal of the zero-crossing detection submodule 120, the second input terminal of the zero-crossing detection submodule 120 is also connected to the output terminal of the voltage generation submodule 130, the output terminal of the zero-crossing detection submodule 120 is connected to the main control unit, the input terminal of the voltage generation submodule 130 is connected to the output terminal of the rectifier submodule 110, and the output terminal of the voltage generation submodule 130 is also connected to the self-locking module 200.

[0056] In the control module 100, the rectifier submodule 110 is used to rectify the grid signal to obtain a rectified signal; the voltage generation submodule 130 is used to generate a control voltage VCC based on the rectified signal output by the rectifier submodule 110; and the zero-crossing detection submodule 120 is used to detect the zero-crossing time based on the rectified signal and the control voltage VCC, and output the zero-crossing control signal V_ZERO to the main control unit.

[0057] Among them, the rectifier submodule 110 can be a full-bridge rectifier, which is a rectifier formed by four diodes. The full-bridge rectifier is connected to the power grid signal through the first switch KEY1. That is, when the first switch KEY1 is closed, the full-bridge rectifier rectifies the AC power grid signal and outputs a rectified signal.

[0058] Specifically, when the first switch KEY1 is closed, the rectifier submodule 110 rectifies the grid signal to obtain a rectified signal, which is a swivel wave. The zero-crossing detection submodule 120 performs zero-crossing detection on the rectified signal to obtain a zero-point control signal V_ZERO, where the zero-crossing time of the rectified signal is also the zero-crossing time of the grid signal. When the zero-crossing detection submodule 120 detects the zero-crossing time of the grid signal, it sends the zero-point control signal V_ZERO to the main control unit. Upon receiving the zero-point control signal V_ZERO, the main control unit sends a start control signal ZERO-K to the self-locking module 200.

[0059] Among them, the zero-point control signal V_ZERO is a low-level signal. That is, when the main control unit receives the low-level zero-point control signal V_ZERO, the main control unit will output a high-level start control signal ZERO-K to the self-locking module 200 to start the self-locking module 200.

[0060] In some alternative embodiments, refer to Figure 1 and Figure 2 The zero-crossing detection submodule 120 includes a zero-crossing voltage divider unit 121 and a zero-crossing switching unit 122.

[0061] The input terminal of the zero-crossing voltage divider unit 121 is connected to the output terminal of the rectifier submodule 110. The control terminal of the zero-crossing switching unit 122 is connected to the output terminal of the zero-crossing voltage divider unit 121, the input terminal of the zero-crossing switching unit 122 is connected to the output terminal of the voltage generation submodule 130, and the output terminal of the zero-crossing switching unit 122 is connected to the main control unit.

[0062] Among them, the zero-crossing voltage divider unit 121 is used to output a zero-crossing voltage divider signal based on the rectified signal for conducting through the zero-crossing voltage divider unit 121; the zero-crossing switch unit 122 is used to output a low-level zero-point control signal V_ZERO to the main control unit when it is turned on.

[0063] Further combined with reference Figure 1 and Figure 2 The zero-crossing voltage divider unit 121 includes resistors R15, R16, and R17. The first end of resistor R15 is connected to the rectifier submodule 110, the second end of resistor R15 is connected to the first end of resistor R17, the second end of resistor R17 is grounded, the first end of resistor R16 is connected to the first end of resistor R17, and the second end of resistor R16 is connected to the control terminal of the zero-crossing switch unit 122.

[0064] Furthermore, the zero-crossing switching unit 122 includes a switching transistor Q5, a resistor R6, and a resistor R19. The second terminal of resistor R16 is connected to the base of switching transistor Q5, the emitter of switching transistor Q5 is connected to the first terminal of resistor R19, the collector of switching transistor Q5 is connected to the second terminal of resistor R6, the second terminal of resistor R19 is grounded, the first terminal of resistor R6 is connected to the output terminal of voltage generation submodule 130, and the second terminal of resistor R6 is also connected to the output terminal of voltage generation submodule 130 to receive the control voltage VCC output by voltage generation submodule 130. Switching transistor Q5 is an NPN type switching transistor.

[0065] The forward voltage of switch Q5 is very small, at 0.7V. Switch Q5 turns on near its zero-crossing point. Specifically, at the instant the first switch KEY1 closes, the rectifier module 110 outputs a rectified signal. Resistors R15 and R17 in the zero-crossing voltage divider unit 121 are connected in series to divide the rectified signal output by the rectifier module 110, obtaining the zero-crossing voltage divider signal for switch Q5. This zero-crossing voltage divider signal is input to the base of switch Q5 through resistor R16. Because the forward voltage of switch Q5 is very small, close to zero, the turn-on time of switch Q5 can be considered as the zero-crossing time of the zero-crossing voltage divider signal, which is also the zero-crossing time of the rectified signal, thus allowing detection of the zero-crossing time of the rectified signal. Figure 2As shown, when the rectified signal approaches zero, resistor R17 divides the voltage to obtain a zero-crossing voltage signal. Under the action of the zero-crossing voltage signal, switch Q5 is turned on, pulling down the voltage at the collector of switch Q5. As a result, the zero-crossing control signal V_ZERO is low. When the main control unit receives the zero-crossing control signal V_ZERO, it counts once. Thus, when the main control unit receives the low-level zero-crossing control signal V_ZERO, it can determine the zero-crossing time of the power grid signal.

[0066] In some alternative embodiments, refer to Figure 1 and Figure 2 The voltage generation submodule 130 includes a power amplifier unit 131 and a regulated output unit 132.

[0067] The power amplifier unit 131 has its input terminal connected to the output terminal of the rectifier submodule 110. The voltage regulator output unit 132 has its input terminal connected to the output terminal of the power amplifier unit 131, and its output terminal connected to the second input terminal of the self-locking module 200 and the zero-crossing detection submodule 120. The voltage regulator output unit 132 is used to output a control voltage VCC based on the power amplifier unit 131 being turned on.

[0068] Reference Figure 2 The power amplifier unit 131 can be a two-stage power amplifier circuit. This two-stage power amplifier circuit includes switching transistors Q1, Q2, and Q4, resistors R2 and R4. Switches Q1, Q2, and Q4 are NPN type switching transistors.

[0069] In this circuit, the first end of resistor R1 is connected to the output terminal of rectifier module 110, and the first end of resistor R1 is also connected to the first end of capacitor CE1. The second end of capacitor CE1 is grounded. The collector of switching transistor Q1 is connected to the second end of resistor R1, the emitter of switching transistor Q1 is connected to the output terminal of voltage regulator output unit 132, and the base of switching transistor Q1 is connected to the emitter of switching transistor Q2. The collector of switching transistor Q2 is connected to the second end of resistor R2, the first end of resistor R2 is connected to the second end of resistor R1, and the base of switching transistor Q2 is connected to the collector of switching transistor Q4. Both the emitter and base of switching transistor Q4 are connected to voltage regulator output unit 132.

[0070] Reference Figure 1 The voltage regulation output unit 132 includes a Zener diode DZ1, resistors R3, R10 and R11.

[0071] In this circuit, the anode of Zener diode DZ1 is grounded, and the cathode of Zener diode DZ1 is connected to the emitter of switching transistor Q4 in power amplifier unit 131. The first terminal of resistor R10 is connected to the base of switching transistor Q4 in power amplifier unit 131. The second terminal of resistor R10 is connected to the first terminals of resistors R3 and R11. The second terminal of resistor R11 is connected to the anode of Zener diode DZ1. The second terminal of resistor R3 is connected to the second input terminal of self-locking module 200 and zero-crossing detection submodule 120. Specifically, the second terminal of resistor R3 is connected to the first terminal of resistor R6 in zero-crossing switching unit 122. The second terminal of resistor R3 serves as the output terminal of the output control voltage VCC of voltage generation submodule 130.

[0072] When the first switch KEY1 is closed, the rectified signal is filtered by capacitor CE1 to obtain a DC signal. This DC signal provides the turn-on voltage for switch Q2 through resistors R1 and R14. When switch Q2 is turned on, switch Q1 receives the turn-on voltage and turns on, thus turning on switch Q4. Under the voltage regulation of Zener diode DZ1, the magnitude of control voltage VCC can be adjusted by adjusting the resistance values ​​of resistors R3 and R11. The formula for calculating control voltage VCC is: VCC = (V1 + Vth) / R11 * (R3 + R11). Where, the voltage regulation value of Zener diode DZ1 is V1, Vth is the turn-on voltage drop of switch Q4, VCC is the voltage value of control voltage VCC, R11 is the resistance value of resistor R11, and R3 is the resistance value of resistor R3.

[0073] In some alternative embodiments, refer to Figure 1 and Figure 2 The self-locking module 200 includes a zero-point start submodule 210, a pulse signal generation submodule 220, and a self-locking submodule 230.

[0074] The zero-point start submodule 210 is connected to the main control unit and the control module 100. The pulse signal generation submodule 220 is connected to the zero-point start submodule 210. The first and second input terminals of the self-locking submodule 230 are respectively connected to the output terminal of the pulse signal generation submodule 220 and the control module 100, and the output terminal of the self-locking submodule 230 is connected to the control terminal of the grid-connected switch module 300.

[0075] Specifically, the first input terminal of the zero-point start submodule 210 is connected to the main control unit, and the first input terminal of the zero-point start submodule 210 is used to receive the start control signal ZERO_K output by the main control unit; the second input terminal of the zero-point start submodule 210 is connected to the voltage regulator output unit 132, and the second input terminal of the zero-point start submodule 210 is used to receive the control voltage VCC output by the voltage regulator output unit 132.

[0076] In the self-locking module 200, the zero-point start submodule 210 is used to start based on the start control signal ZERO_K output by the main control unit; the pulse signal generation submodule 220 is used to generate a pulse signal based on the charging of the control voltage VCC when the zero-point start submodule 210 starts; the self-locking submodule 230 is used to perform conduction self-locking based on the pulse signal and the control voltage VCC, so as to output a self-locking control signal for controlling the grid-connected switch module 300 to maintain closed locking.

[0077] Specifically, the zero-point start submodule 210 starts when the start control signal ZERO_K is output by the main control unit, so as to input the control voltage VCC to the pulse signal generation submodule 220. The pulse signal generation submodule 220 generates a pulse signal based on the control voltage VCC and outputs the pulse signal to the self-locking submodule 230. The self-locking submodule 230 performs conduction self-locking based on the pulse signal and the control voltage VCC and generates a self-locking control signal so that the grid-connected switch module 300 remains closed and locked.

[0078] Further combined with reference Figure 1 and Figure 2 The zero-point start-up submodule 210 includes a switch Q8 and a resistor R18. The switch Q8 is an NPN type switch.

[0079] In this circuit, the base of switching transistor Q8 is connected to the main control unit via resistor R18 to receive the start control signal ZERO_K sent by the main control unit. The emitter of switching transistor Q8 is connected to the input terminal of the pulse signal generation submodule 220. The collector of switching transistor Q8 is connected to the voltage regulation output unit 132. Specifically, the collector of switching transistor Q8 is connected to the second terminal of resistor R3 in the voltage regulation output unit 132, and the collector of switching transistor Q8 is used to receive the control voltage VCC output by the voltage regulation output unit 132.

[0080] Switch Q8 is turned on when a high-level start control signal ZERO_K is received. Specifically, when the control unit receives a low-level zero-point control signal V_ZERO from the zero-crossing detection submodule 120, it outputs a high-level start control signal ZERO_K, thereby turning on switch Q8 to transmit the control voltage VCC to the pulse signal generation submodule 220.

[0081] In some optional embodiments, the pulse signal generation submodule 220 includes a switching transistor Q7, a first oscillation unit 221, and a second oscillation unit 222. The emitter of the switching transistor Q7 is connected to the output terminal of the zero-point start-up submodule 210, the collector of the switching transistor Q7 is connected to the input terminal of the first oscillation unit 221, and the base of the switching transistor Q7 is connected to the input terminal of the second oscillation unit 222; the input terminal of the self-locking submodule 230 is connected to the output terminal of the second oscillation unit 222.

[0082] In the pulse signal generation submodule 220, the switching transistor Q7 is used to turn on when the zero-point start submodule 210 is started; the first oscillation unit 221 and the second oscillation unit 222 are used to charge and store energy based on the control voltage VCC output by the voltage regulator output unit 132 in the control module 100 when the switching transistor Q7 is turned on, so as to output a pulse signal to the self-locking submodule 230.

[0083] Specifically, when switch Q8 is turned on, switch Q7 is turned on, the first oscillation unit 221 and the second oscillation unit 222 charge and store energy based on the control voltage VCC, and output pulse signals to the self-locking submodule 230.

[0084] Optionally, the first oscillation unit 221 and the second oscillation unit 222 can be RC oscillation units. In other embodiments, they can also be other oscillation units, and no specific limitation is made here. In this embodiment, an RC oscillation unit is used as an example for illustration.

[0085] In one specific embodiment, the first oscillation unit 221 includes a resistor R7 and a capacitor C3. The first end of the resistor R7 is connected to the collector of the switching transistor Q7, the second end of the resistor R7 is connected to the first end of the capacitor C3, and the second end of the capacitor C3 is grounded; and one end of the capacitor C3 is connected to the self-locking submodule 230.

[0086] In one specific embodiment, the second oscillation unit 222 includes a resistor R8 and a capacitor C1. The first terminal of the capacitor C1 is connected to the base of the switching transistor Q7, and the second terminal of the capacitor C1 is connected to the first terminal of the resistor R8, the second terminal of the resistor R8 being grounded.

[0087] At the instant the first switch KEY1 closes, when the zero-crossing detection submodule 120 detects the zero-crossing point of the power grid signal, its switch Q5 turns on, and it outputs a low-level zero-crossing control signal V_ZERO to the main control unit. Simultaneously, the main control unit outputs a high-level start control signal ZERO_K to the base of switch Q8. At the same time, at the instant the first switch KEY1 closes, the voltage generation submodule 130 outputs a control voltage VCC based on the rectified signal to the collector of switch Q8. Thus, switch Q8 turns on upon receiving the high-level start control signal ZERO_K and the control voltage VCC. When switch Q8 turns on, switch Q7 also turns on, causing capacitors C1 and C3 to begin charging. When capacitors C1 and C3 are charged to near the control voltage VCC, the base and emitter voltages of switch Q7 become equal, causing Q7 to turn off. During the conduction process, the switching transistor Q7 outputs the pulse signal generated by the charging of the first oscillation unit 221 to the self-locking submodule 230.

[0088] In this embodiment, the grid-connected switch module 300 can be a relay, which includes a control terminal and an output switch terminal. The control terminal corresponds to the two pins of the relay coil, namely pin 1 and pin 2, and the two pins of the output switch terminal, namely pin 3 and pin 4, are normally open by default. Specifically, pin 4 of the relay is connected to the load RL connected to the live wire of the power grid, pin 3 of the relay is connected to the neutral wire of the power grid, pin 1 of the relay is connected to the self-locking submodule 230, and pin 2 of the relay is grounded; furthermore, a Zener diode (TVS1) is connected between pin 1 and pin 2.

[0089] In some alternative embodiments, refer to Figure 1 and Figure 2 The self-locking submodule 230 includes a first switching unit 231 and a second switching unit 232.

[0090] The control terminal of the first switching unit 231 is connected to the pulse signal generation submodule 220, the control terminal of the second switching unit 232 is connected to the output terminal of the first switching unit 231 and the control module 100, and the output terminal of the second switching unit 232 is connected to the control terminal of the grid-connected switch module 300. The first switching unit 231 and the second switching unit 232 maintain conduction lock based on the pulse signal and the control voltage VCC, and output a self-locking control signal for controlling the grid-connected switch module 300 to maintain closed lock.

[0091] Specifically, the first switching unit 231 includes a switching transistor Q3, a resistor R9, and a resistor R13. The emitter of the switching transistor Q3 is connected to the second terminal of the resistor R3 in the voltage regulation output unit 132 of the voltage generation submodule 130 to receive the control voltage VCC output by the voltage regulation output unit 132. The collector of the switching transistor Q3 is connected to the first terminal of the resistor R9, and the second terminal of the resistor R9 is connected to the first terminal of the resistor R13, which is grounded. The collector of the switching transistor Q3 is also connected to the control terminal of the grid-connected switching module 300; specifically, the collector of the switching transistor Q3 is connected to the control terminal of the relay. The switching transistor Q3 is a PNP type.

[0092] The second switching unit 232 includes a switching transistor Q6 and a resistor R5. The base of switching transistor Q6 is connected to the second terminal of resistor R7 in the first oscillation unit 221 of the pulse signal generation submodule 220. The base of switching transistor Q6 is also connected to the first terminal of resistor R13. The emitter of switching transistor Q6 is grounded, and the collector of switching transistor Q6 is connected to the second terminal of resistor R5. The first terminal of resistor R5 is connected to the base of switching transistor Q3. Switching transistor Q6 is a PNP type switching transistor.

[0093] Specifically, at the instant the first switch KEY1 is closed, when the zero-point start-up submodule 210's switch Q8 turns on, switch Q7 also turns on, causing capacitors C3 and C1 to charge. When capacitor C3 charges to a certain level, the base voltage of switch Q6 is greater than its emitter voltage, thus turning on switch Q6. Switch Q6 pulls down the base voltage of switch Q3, causing switch Q3 to also turn on. The control voltage VCC passes through switch Q3, resistor R9, and resistor R13, obtaining a high level at the second terminal of resistor R9. This high level is input to the base of switch Q6, keeping switch Q6 continuously conducting. Even if power is subsequently cut off (CPU power failure), switch Q8 turns off, causing Q7 to turn off, but switch Q3 and switch Q6 remain conducting.

[0094] Because the switching transistor Q3 is always on, the control terminal of the relay can continuously receive a voltage signal, thereby closing the relay's output switch terminal, i.e., closing pins 3 and 4 of the relay. This keeps the load RL in a power-on locked state, ensuring that the working circuit of the load RL is always conducting, thus preventing the load RL from being accidentally powered down and improving system stability. Understandably, the grid-connected switch module 300 conducts at the zero point of the grid signal, effectively preventing arcing.

[0095] In this embodiment, the self-locking control signal output by the self-locking module 200 is used to control two pins of the relay coil. By controlling pins 1 and 2, the switch between pins 3 and 4 is closed. Thus, when the power supply voltage of the grid-connected switch module 300 is unexpectedly disconnected, the switch of the load RL can be kept locked, thereby preventing the load RL from being unexpectedly powered down and providing stability. At the same time, the grid-connected switch module is turned on at the zero point of the grid signal, which can effectively prevent arcing.

[0096] In some optional embodiments, the circuit further includes a second switch KEY2. The second switch KEY2 is connected to the control terminal of the first switch unit 231, and the second switch KEY2 is used to control the first switch unit 231 to open when closed so that the self-locking submodule 230 is released from its self-locking state, thereby controlling the grid-connected switch module 300 to open.

[0097] The second switch KEY2 controls whether the self-locking submodule 230 outputs a self-locking control signal. When the second switch KEY2 is open, the self-locking submodule 230 operates normally and can output a self-locking control signal, thereby enabling the self-locking of the relay RLY1 in the grid-connected switch module 300, ensuring that the load RL is always energized. When the second switch KEY2 is closed, the self-locking submodule 230 stops operating and no longer outputs a self-locking control signal, thus deactivating the relay RLY1 in the grid-connected switch module 300 and de-energizing the load RL.

[0098] Specifically, the first end of the second switch KEY2 is connected to the emitter of the switching transistor Q3, and the second end of the second switch KEY2 is connected to the base of the switching transistor Q3, so that the second switch KEY2 can control the value of VBE of the switching transistor Q3.

[0099] When the second switch KEY2 is closed, the base and emitter of the switching transistor Q3 are short-circuited, so the VBE of the switching transistor Q3 is approximately equal to 0, causing the switching transistor Q3 to be turned off, which in turn causes the switching transistor Q6 to be turned off. As a result, the self-locking submodule 230 stops working and no longer outputs the self-locking control signal, thus the relay RLY1 in the grid-connected switch module 300 is disconnected, and the load RL is de-energized.

[0100] In the above embodiments, when an emergency stop is required, the power to the load RL can be cut off simply by pressing the second switch KEY2, without having to operate the first switch KEY1 on the high-voltage side, thus preventing electric shock.

[0101] In some alternative embodiments, the circuit further includes a capacitor C2. The capacitor C2 is connected across the second switch KEY2, and is used to ensure that the voltage across the second switch KEY2 is equal when the second switch KEY2 is closed.

[0102] In this configuration, the first end of capacitor C2 is connected to the first end of the second switch KEY2, the second end of capacitor C2 is connected to the second end of resistor R5, and the first end of resistor R5 is connected to the second end of the second switch KEY2 and the base of the switching transistor Q3. This ensures that the voltage across the second switch KEY2 is as equal as possible when the switch is closed, thus preventing arcing of the second switch KEY2.

[0103] Secondly, this application provides an electronic device including a load self-locking circuit according to any of the above embodiments.

[0104] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0105] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A load self-locking circuit, characterized in that, include: A first switch, wherein a first end of the first switch is used to connect to a power grid signal, and a second end of the first switch is connected to a first end of a load; The control module is connected to the main control unit and the second terminal of the first switch. The control module is used to detect the zero-crossing time of the power grid signal when the first switch is closed so as to output a zero-crossing control signal to the main control unit, and to generate a control voltage when the first switch is closed. The self-locking module is connected to the control module and the main control unit. The self-locking module is used to start at the zero-crossing point based on the start control signal of the main control unit and the control voltage, and to generate a self-locking control signal after starting. The start control signal is used to be issued when the main control unit receives the zero-point control signal. A grid-connected switch module, wherein the control terminal and the output switch terminal of the grid-connected switch module are respectively connected to the output terminal of the self-locking module and the second terminal of the load, and the grid-connected switch module is used to self-lock based on the self-locking control signal at the zero crossing point so that the load is in a energized state; The self-locking module includes: A zero-point start submodule is connected to the main control unit and the control module. The zero-point start submodule is used to start based on the start control signal output by the main control unit. A pulse signal generation submodule is provided, which is connected to the zero-point start-up submodule. The pulse signal generation submodule is used to generate a pulse signal based on the control voltage charging when the zero-point start-up submodule is started. The self-locking submodule has its first and second input terminals connected to the output terminal of the pulse signal generation submodule and the control module, respectively. The output terminal of the self-locking submodule is connected to the control terminal of the grid-connected switch module. The self-locking submodule is used to perform conduction self-locking based on the pulse signal and the control voltage, so as to output a self-locking control signal for controlling the grid-connected switch module to maintain closed locking.

2. The circuit according to claim 1, characterized in that, The control module includes a rectification submodule, a zero-crossing detection submodule, and a voltage generation submodule; The input terminal of the rectifier submodule is connected to the power grid signal through the first switch. The output terminal of the rectifier submodule is connected to the first input terminal of the zero-crossing detection submodule. The second input terminal of the zero-crossing detection submodule is connected to the output terminal of the voltage generation submodule. The output terminal of the zero-crossing detection submodule is connected to the main control unit. The input terminal of the voltage generation submodule is connected to the output terminal of the rectifier module. The output terminal of the voltage generation submodule is also connected to the self-locking module. The rectifier submodule is used to rectify the power grid signal to obtain a rectified signal; the voltage generation submodule is used to generate a control voltage based on the rectified signal output by the rectifier submodule. The zero-crossing detection submodule is used to detect the zero-crossing time based on the rectified signal and the control voltage, and output the zero-crossing control signal to the main control unit.

3. The circuit according to claim 2, characterized in that, The zero-crossing detection submodule includes: A zero-crossing voltage divider unit, the input of which is connected to the output of the rectifier submodule; The zero-crossing switching unit has its control terminal connected to the output terminal of the zero-crossing voltage divider unit, its input terminal connected to the output terminal of the voltage generation submodule, and its output terminal connected to the main control unit. The zero-crossing voltage divider unit is used to output a zero-crossing voltage divider signal to turn on the zero-crossing switching unit based on the rectified signal; The zero-crossing switch unit is used to output a low-level zero-point control signal to the main control unit when it is turned on.

4. The circuit according to claim 2, characterized in that... The voltage generation submodule includes: A power amplifier unit, the input of which is connected to the output of the rectifier submodule; A voltage regulator output unit, wherein the input terminal of the voltage regulator output unit is connected to the output terminal of the power amplifier unit, and the output terminal of the voltage regulator output unit is connected to the second input terminal of the self-locking module and the zero-crossing detection submodule; The regulated output unit is used to output a control voltage based on the power amplifier unit being turned on.

5. The circuit according to claim 1, characterized in that, The zero-point startup submodule includes: Switch Q8, the base of which is connected to the main control unit, the emitter of which is connected to the pulse signal generation submodule, and the collector of which is connected to the control module; The switching transistor Q8 is used to turn on when a high-level start control signal is received.

6. The circuit according to claim 1, characterized in that, The pulse signal generation submodule includes a switching transistor Q7, a first oscillation unit, and a second oscillation unit. The emitter of the switching transistor Q7 is connected to the zero-point start-up submodule, the collector of the switching transistor Q7 is connected to the first oscillation unit, and the base of the switching transistor Q7 is connected to the second oscillation unit; the self-locking submodule is connected to the second oscillation unit. The switching transistor Q7 is used to turn on when the zero-point start-up submodule is started; the first oscillation unit and the second oscillation unit are used to charge and store energy based on the control voltage output by the control module when the switching transistor Q7 is turned on, so as to output the pulse signal to the self-locking submodule.

7. The circuit according to claim 1, characterized in that, The self-locking submodule includes a first switching unit and a second switching unit; The control terminal of the first switching unit is connected to the pulse signal generation submodule, the control terminal of the second switching unit is connected to the output terminal of the first switching unit and the control module, and the output terminal of the second switching unit is connected to the control terminal of the grid-connected switching module. The first switching unit and the second switching unit maintain conduction lock based on the pulse signal and the control voltage, and output a self-locking control signal for controlling the grid-connected switch module to maintain closed lock.

8. The circuit according to claim 7, characterized in that, The circuit also includes: The second switch is connected to the control terminal of the first switch unit. When closed, the second switch controls the first switch unit to open so that the self-locking submodule can release its self-locking state, thereby controlling the grid-connected switch module to open.

9. An electronic device, characterized in that, Includes the load self-locking circuit according to any one of claims 1-8.

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