Contactor control circuit and contactor

Abstract

The utility model discloses a contactor control circuit and a contactor. The contactor control circuit comprises a first power supply module, a control module, a driving module and a turn-off module, the first power supply module is connected with the power input end of the control module; the control module is provided with a fault output end connected with the driving module so as to output a trigger signal to the driving module through the fault output end in the turn-off stage of the contactor; the driving module is used for responding to the trigger signal to be switched on, so that the turn-off module and the fault output end are electrically switched on; and the turn-off module is used for discharging current in a contactor coil when the turn-off module is electrically connected with the fault output end, so that the contactor can be quickly turned off. The contactor control circuit can be applied to a high-voltage application scene, the application scene is expanded, and the adaptability is wider.

Description

Technical Field

[0001] This application relates to the field of contactor technology, specifically to a contactor control circuit and a contactor. Background Technology

[0002] A contactor is an electrical device used to control circuits, primarily for frequently connecting and disconnecting high-current loads. It is currently widely used in motor control, lighting systems, heating equipment, and other applications.

[0003] When the contactor coil is energized, it generates a magnetic field that attracts the armature, causing the contacts to close and connecting the circuit. When the coil is de-energized, the magnetic field disappears, the armature resets under the action of the spring, the contacts open, and the circuit is disconnected.

[0004] However, the contactor control chips in related technologies are limited to low-voltage applications due to voltage requirements. Utility Model Content

[0005] In view of the above problems, this application provides a contactor control circuit and a contactor to solve the above technical problems.

[0006] In a first aspect, this application provides a contactor control circuit, which includes a first power supply module, a control module, a drive module, and a shutdown module. The first power supply module is connected to the power input terminal of the control module to output a power supply voltage to the power input terminal. The power supply voltage is obtained by rectifying and stepping down AC high voltage by the first power supply module. The control module is configured with a fault output terminal connected to the drive module to output a trigger signal to the drive module through the fault output terminal during the contactor shutdown phase. A first terminal of the drive module is connected to the shutdown module, and a second terminal is connected to the fault output terminal, for conducting in response to the trigger signal to electrically connect the shutdown module and the fault output terminal. The shutdown module is connected to the contactor coil to discharge the current in the contactor coil when electrically connected to the fault output terminal, so that the contactor can quickly shut off.

[0007] In one possible implementation of this application, the first power supply module includes a first rectifier unit and a step-down unit; the first rectifier unit is connected to the step-down unit to output a first DC high voltage to the step-down unit; the first DC high voltage is a voltage signal obtained by rectifying AC high voltage; the step-down unit is connected to the power input terminal to output a supply voltage to the power input terminal; the supply voltage is a voltage signal obtained by stepping down the first DC high voltage.

[0008] In one possible implementation of this application, the step-down unit includes a first resistor branch, a first voltage regulator branch, a step-down transistor, and a second resistor branch; the first end of the first resistor branch and the first end of the second resistor branch are connected to the output terminal of the first rectifier unit, the second end of the first resistor branch and the second end of the first voltage regulator branch are connected to the base of the step-down transistor, the first end of the first voltage regulator branch is connected to the ground terminal, the collector of the step-down transistor is connected to the second end of the second resistor branch, and the emitter of the step-down transistor is connected to the power input terminal.

[0009] In one possible implementation of this application, the control module is further configured with a working voltage output terminal, the drive module includes a drive switch unit, the control terminal of the drive switch unit is connected to the working voltage output terminal, the first terminal of the drive switch unit is connected to the shutdown module, and the second terminal of the drive switch unit is connected to the fault output terminal.

[0010] In one possible implementation of this application, the shutdown module includes a shutdown switch unit, a freewheeling unit, and an energy storage unit; the second end of the freewheeling unit is connected to the first end of the contactor coil, and the first end of the freewheeling unit is connected to the first end of the shutdown switch unit and the first end of the energy storage unit; the second end of the energy storage unit is connected to the control end of the shutdown switch unit and the first end of the drive module, respectively; the second end of the shutdown switch unit, the second end of the contactor coil, and the controllable switch on the main circuit where the contactor coil is located are connected.

[0011] In one possible implementation of this application, the shutdown module further includes a voltage clamping unit. The first end of the voltage clamping unit is connected to the control terminal of the shutdown switch unit, and the second end of the voltage clamping unit is connected to the second end of the shutdown switch unit. The voltage clamping unit includes a current-limiting diode and a clamping diode connected to each other at their anodes. The cathode of the current-limiting diode is connected to the control terminal of the shutdown switch unit, and the cathode of the clamping diode is connected to the second end of the shutdown switch unit.

[0012] In one possible implementation of this application, the contactor control circuit further includes a voltage divider detection module, which is connected to the voltage detection terminal of the control module and the first rectifier unit to output the voltage detection value obtained based on the first DC high voltage to the voltage detection terminal; the control module is also used to control the output of a drive signal based on the voltage detection value; the drive signal is used to control the controllable switch on the main circuit where the contactor coil is located.

[0013] In one possible implementation of this application, the contactor control circuit further includes a current detection module and a current setting module; the current detection module is connected to the main circuit of the contactor coil and the current detection terminal of the control module to output the detected current value of the main circuit where the contactor coil is located to the current detection terminal; the current setting module is connected to the current setting terminal of the control module; the control module is further used to adjust the duty cycle of the controllable switch in the main circuit where the contactor coil is located according to the current detection value and the configuration resistor of the current setting module, so that the current value of the contactor coil during the pull-in stage and the holding stage is maintained at the corresponding preset current value.

[0014] In one possible implementation of this application, the contactor control circuit further includes a switching duration setting module. The switching duration setting module includes a configuration capacitor. One end of the configuration capacitor is connected to the duration setting terminal of the control module, and the other end is connected to the ground terminal, so as to configure the switching duration of the contactor from the energizing stage to the holding stage according to the capacitance value of the configuration capacitor.

[0015] Secondly, this application also provides a contactor that includes a contactor control circuit as described in any possible implementation of the first aspect.

[0016] In one possible implementation of this application, the contactor further includes a power supply module and a second power supply module. The power supply module is connected to the first power supply module and the second power supply module respectively to output AC high voltage to the first power supply module and the second power supply module. The second power supply module includes a second rectifier unit, which is connected to the contactor coil to output a second DC high voltage to the contactor coil. The second DC high voltage is a voltage signal obtained by rectifying the AC high voltage.

[0017] From the above, it can be concluded that this application has the following beneficial effects:

[0018] In this application, the AC high-voltage power is rectified and stepped down by the first power supply module to obtain a power supply voltage output to the power input terminal of the control module. The fault output terminal of the control module is connected to the drive module. During the contactor turn-off phase, a trigger signal is output to the drive module, enabling the drive module to conduct in response to the trigger signal, thereby disconnecting the electrical connection between the turn-off module and the fault output terminal, releasing the current in the contactor coil, and allowing the contactor to turn off quickly. During the contactor engagement and holding phases, the control module does not output a trigger signal. Therefore, the drive module is disconnected, which can block the high voltage and protect the fault output terminal. This ensures that the contactor control circuit can be used in high-voltage application scenarios, expanding the application scenarios and making it more adaptable. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0020] Figure 1 This is a schematic block diagram of a contactor control circuit provided in an embodiment of this application;

[0021] Figure 2 This is a schematic block diagram of the first power supply module provided in the embodiments of this application;

[0022] Figure 3 This is a schematic block diagram of a step-down unit provided in the embodiments of this application;

[0023] Figure 4 This is a schematic diagram of a contactor control circuit provided in an embodiment of this application.

[0024] Figure 5 This is a schematic diagram of a driver module provided in an embodiment of this application;

[0025] Figure 6 This is a schematic diagram of a shutdown module provided in the embodiments of this application;

[0026] Figure 7 This is another principle block diagram of the shutdown module provided in the embodiments of this application;

[0027] Figure 8 This is another principle block diagram of the contactor control circuit provided in the embodiments of this application;

[0028] Figure 9 This is another block diagram of the contactor control circuit provided in the embodiments of this application;

[0029] Figure 10 This is a schematic block diagram of a contactor provided in an embodiment of this application;

[0030] Figure 11 This is a schematic diagram of the circuit principle of a power module provided in the embodiments of this application. Detailed Implementation

[0031] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0032] To enable those skilled in the art to better understand the solutions of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0033] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0034] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0035] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0036] Furthermore, in the embodiments of this application, "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.

[0037] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0038] In the embodiments of this application, the first terminal / first end of each transistor is one of the source and the drain, and the second terminal / second end of each transistor is the other of the source and the drain. Since the source and drain of a transistor can be structurally symmetrical, they can be structurally indistinguishable. That is, the first terminal / first end and the second terminal / second end of the transistor in the embodiments of this application can be structurally indistinguishable. For example, when the transistor is a P-type transistor, the first terminal / first end is the source, and the second terminal / second end is the drain; for example, when the transistor is an N-type transistor, the first terminal / first end is the drain, and the second terminal / second end is the source.

[0039] In the circuit structure provided by the embodiments of this application, nodes such as the first node and the second node do not represent actual existing components, but rather represent the junction points of related couplings in the circuit diagram. In other words, these nodes are equivalent to the junction points of related couplings in the circuit diagram.

[0040] The contactor control circuit and contactor provided in this application will be described in detail below.

[0041] First, this application provides a contactor control circuit that can be applied to a contactor to control its operation.

[0042] Please see Figure 1 , Figure 1 This is a schematic block diagram of a contactor control circuit provided in the embodiments of this application. The contactor control circuit 100 may include a first power supply module 110, a control module 120, a drive module 130, and a shutdown module 140. The first power supply module 110 is connected to the power input terminal VIN of the control module 120 to output a power supply voltage to the power input terminal VIN. This power supply voltage is obtained by rectifying and stepping down AC high-voltage electricity through the first power supply module 110. The control module 120 is configured with a fault output terminal FO connected to the drive module 130 to output a trigger signal to the drive module 130 during the contactor shutdown phase. The first end of the drive module 130 is connected to the shutdown module 140, and the second end is connected to the fault output terminal FO. This can be used to conduct in response to the trigger signal, thereby electrically connecting the shutdown module 140 and the fault output terminal FO. The shutdown module 140 is connected to the contactor coil 200 and can be used to discharge the current in the contactor coil 200 when electrically connected to the fault output terminal FO, so that the contactor can quickly shut off.

[0043] In this embodiment of the application, the first power supply module 110 can be connected to a power supply terminal (not shown in the figure) to access AC high voltage. The power supply terminal can be a mains power output terminal or other power output terminal, which can be determined according to the actual application scenario and is not limited here.

[0044] The first power supply module 110 can rectify the incoming high-voltage AC power into DC power, and then step down the DC power to obtain the supply voltage. This supply voltage is input to the power input terminal VIN of the control module 120 to power the control module 120.

[0045] The fault output terminal FO of the control module 120 is connected to the drive module 130. During the contactor turn-off phase, the control module 120 outputs a trigger signal to the drive module 130 through the fault output terminal FO, so that the drive module 130 can be turned on. The fault output terminal FO is electrically connected to the turn-off module 140 through the turned-on drive module 130, so as to quickly discharge the current on the contactor coil 200.

[0046] During the contactor engagement and holding phases, the fault output terminal FO is configured to be in a floating state with no trigger signal output. At this time, the drive module 130 is in a disconnected state, which electrically disconnects the shutdown module 140 from the fault output terminal FO, thus preventing high voltage from damaging the control module 120.

[0047] The control module 120 can use any existing contactor control chip, such as the SCCK0800BEE or SCCK0800BS chip. The specific chip can be determined according to the actual application scenario, and no limitation is made here.

[0048] In this embodiment, the AC high-voltage power is rectified and stepped down by the first power supply module 110 to obtain a power supply voltage output to the power input terminal VIN of the control module 120. The fault output terminal FO of the control module 120 is connected to the drive module 130. During the contactor turn-off phase, a trigger signal is output to the drive module 130, so that the drive module 130 can turn on in response to the trigger signal, thereby electrically connecting the turn-off module 140 and the fault output terminal FO, releasing the current in the contactor coil 200 so that the contactor can turn off quickly. During the contactor engagement and holding phases, the control module 120 has no trigger signal output. Therefore, the drive module 130 is disconnected, which can block the high voltage and protect the fault output terminal FO. This ensures that the contactor control circuit 100 can be used in high-voltage application scenarios, expanding the application scenarios and making it more adaptable.

[0049] Next, continue with Figure 1 The unit modules shown are described in detail, as well as the specific implementation methods that may be used in practical applications.

[0050] like Figure 2 As shown, in some embodiments of this application, the first power supply module includes a first rectifier unit 1110 and a step-down unit 1120; the first rectifier unit 1110 is connected to the step-down unit 1120 to output a first DC high voltage to the step-down unit 1120; the first DC high voltage is a voltage signal obtained by rectifying AC high voltage; the step-down unit 1120 is connected to the power input terminal VIN to output the power supply voltage to the power input terminal VIN; the power supply voltage is a voltage signal obtained by stepping down the first DC high voltage.

[0051] In this embodiment, the first rectifier unit 1110 can be any existing rectifier, such as a bridge rectifier or a full-wave rectifier. The specific type can be determined according to the actual application scenario, and is not limited here. The first rectifier unit 1110 rectifies the received AC high-voltage power and outputs a first DC high-voltage power to the step-down unit 1120.

[0052] The step-down unit 1120 can employ any existing step-down circuit, including but not limited to resistor divider circuits and switching regulator circuits. The specific type can be determined based on the actual application scenario and is not limited here. The step-down unit 1120 can step down the received first DC high voltage to a supply voltage within the withstand voltage range of the control module 120, thereby providing safe power to the control module 120.

[0053] like Figure 3 As shown, in one implementation, the step-down unit 1120 may include a first resistor branch 1121, a first voltage regulator branch 1122, a step-down transistor Q4, and a second resistor branch 1123; the first end of the first resistor branch 1121 and the first end of the second resistor branch 1123 are connected to the output terminal of the first rectifier unit 1110, the second end of the first resistor branch 1121 and the second end of the first voltage regulator branch 1122 are connected to the base of the step-down transistor Q4, the first end of the first voltage regulator branch 1122 is connected to the ground terminal PGND, the collector of the step-down transistor Q4 is connected to the second end of the second resistor branch 1123, and the emitter of the step-down transistor Q4 is connected to the power input terminal VIN.

[0054] In this embodiment, the first resistor branch 1121 and the second resistor branch 1123 may include at least one resistor, and the first voltage regulator branch 1122 may include at least one Zener diode. The Zener diode clamps the voltage at the base of the buck transistor Q4, protecting the buck transistor Q4. When the buck transistor Q4 is turned on, the first DC high voltage is reduced by voltage division through the second resistor branch 1123 and the buck transistor Q4 to obtain the supply voltage output to the power input terminal VIN.

[0055] like Figure 4As shown, as an example, the control module 120 is the control chip U1, the first rectifier unit 1110 is the first rectifier bridge BR1, the first resistor branch 1121 includes the sixth resistor R6, the fourteenth resistor R14 and the twelfth resistor R12 connected in series, the second resistor branch 1123 includes the second resistor R2, the eleventh resistor R11 and the ninth resistor R9 connected in series, and the first voltage regulator branch 1122 includes the second voltage regulator diode ZD2, the fourth voltage regulator diode ZD4 and the fifth voltage regulator diode ZD5 connected in series.

[0056] The sixth resistor R6, the fourteenth resistor R14, and the twelfth resistor R12 are connected in series to step down the first high-voltage DC power supply from the first rectifier bridge BR1. The second Zener diode ZD2, the fourth Zener diode ZD4, and the fifth Zener diode ZD5, also connected in series, clamp the voltage at the base of the buck transistor Q4. When the buck transistor Q4 is turned on, the first high-voltage DC power supply is stepped down by the second resistor R2, the eleventh resistor R11, and the ninth resistor R9 to form the power supply voltage output to the power input terminal VIN of the control chip U1. It can be understood that by setting the resistance values ​​of the series resistors, the power supply voltage can be kept within the voltage rating range of the control chip U1, ensuring safe power supply.

[0057] like Figure 5 As shown, in some embodiments of this application, the control module 120 may also be configured with a working voltage output terminal VDD, and the drive module 130 may include a drive switch unit 1301. The control terminal of the drive switch unit 1301 is connected to the working voltage output terminal VDD, the first terminal of the drive switch unit 1301 is connected to the shutdown module 140, and the second terminal of the drive switch unit 1301 is connected to the fault output terminal FO.

[0058] In this embodiment, the operating voltage output terminal VDD of the control module 120 can output a driving voltage to the driving switch unit 1301 when the control module 120 is working. The driving switch unit 1301 can be any existing switching transistor, including but not limited to transistors, metal-oxide-semiconductor field-effect transistors (MOSFETs), insulated gate bipolar transistors (IGBTs), etc. The specific selection can be made according to the actual application scenario, and is not limited here.

[0059] During the contactor's engagement and holding phases, although the working voltage output terminal VDD has a drive voltage output to the drive switch unit 1301, the second terminal of the drive switch unit 1301 is connected to the fault output terminal FO, so the fault output terminal FO is in a floating state. Therefore, the drive switch unit 1301 is not conducting, thus preventing high voltage from damaging the control module 120.

[0060] Combination Figure 4 As an example, the driving switch unit 1301 is the third MOSFET Q3. The control terminal, pin 1, of the third MOSFET Q3 is connected to the working voltage output terminal VDD of the control chip U1 through the seventh diode D7. The first terminal, pin 2, of the third MOSFET Q3 is connected to the shutdown module 140, and the second terminal, pin 3, of the third MOSFET Q3 is connected to the fault output terminal FO.

[0061] During the contactor's engagement and holding phases, the fault output terminal FO is in a floating state. At this time, the third MOSFET Q3 is turned off, blocking the high voltage and protecting the fault output terminal FO, thus preventing the high voltage at the drain from damaging the control chip U1. During the contactor's disengagement phase, the fault output terminal FO outputs a low-level trigger signal, causing the third MOSFET Q3 to conduct, thereby quickly discharging the current from the contactor coil 200.

[0062] like Figure 6 As shown, in some embodiments, the shutdown module 140 may include a shutdown switch unit 1401, a freewheeling unit 1402, and an energy storage unit 1403; the second end of the freewheeling unit 1402 is connected to the first end of the contactor coil 200, and the first end of the freewheeling unit 1402 is connected to the first end of the shutdown switch unit 1401 and the first end of the energy storage unit 1403; the second end of the energy storage unit 1403 is connected to the control terminal of the shutdown switch unit 1401 and the first end of the drive module 130, respectively; the second end of the shutdown switch unit 1401, the second end of the contactor coil 200, and the controllable switch Q2 on the main circuit where the contactor coil 200 is located are connected.

[0063] In this embodiment, the turn-off switching unit 1401 can be any existing switching transistor, including but not limited to transistors, MOSFETs, IGBTs, etc., and the specific selection can be made according to the actual application scenario, without limitation here. The freewheeling unit 1402 can be one or more freewheeling diodes connected in series, and the energy storage unit 1403 can be an energy storage device such as an energy storage capacitor.

[0064] During the contactor turn-off phase, the controllable switch Q2 is open. Due to the presence of the freewheeling unit 1402, the turn-off switch unit 1401 is turned on. The circuit formed by the contactor coil 200, the turn-off switch unit 1401, and the freewheeling unit 1402 forms a coil energy release path. At the same time, the drive module 130 is turned on in response to the trigger signal. The fault output terminal FO can draw current from the energy storage unit 1403 through the turned-on drive module 130, thereby accelerating the current discharge of the contactor coil 200 and enabling the contactor to turn off quickly.

[0065] Please continue reading. Figure 4 As an example, the off-switch unit 1401 is a first MOSFET Q1, the freewheeling unit 1402 is a first diode D1, and the energy storage unit 1403 is a first capacitor C1. The control terminal of the first MOSFET Q1 is connected to the first terminal of the third MOSFET Q3. The first terminal of the first MOSFET Q1 is connected to the anode of the first diode D1. The anode of the first diode D1 is connected to the first terminal of the contactor coil 200. The second terminal of the contactor coil 200 is connected to the second terminal of the first MOSFET Q1 and the first terminal of the controllable switch Q2.

[0066] Understandably, during the contactor turn-off phase, the controllable switch Q2 on the main circuit is open. At this time, due to the presence of the first diode D1, the contactor coil 200, the first MOSFET Q1, and the first diode D1 form a circuit to discharge the current on the contactor coil 200. Simultaneously, because the fault output terminal FO outputs a low-level trigger signal, the third MOSFET Q3 is turned on. Therefore, the fault output terminal FO can extract energy from the discharge circuit through the third MOSFET Q3 and the first capacitor C1. The first capacitor C1 discharges until the first MOSFET Q1 operates in the subthreshold region, increasing the demagnetizing current slope so that the contactor can turn off quickly.

[0067] like Figure 7 As shown, in some embodiments of this application, the shutdown module 140 may further include a voltage clamping unit 1404, the first end of which is connected to the control terminal of the shutdown switch unit 1401, and the second end of which is connected to the second end of the shutdown switch unit 1401.

[0068] As an example, refer to Figure 4 The voltage clamping unit 1404 includes a current-limiting diode D4 and a clamping diode ZD1 connected to each other at their anodes. The cathode of the current-limiting diode D4 is connected to the control terminal of the first MOSFET Q1, and the cathode of the clamping diode ZD1 is connected to the second terminal of the first MOSFET Q1.

[0069] In this embodiment, when an input undervoltage occurs or the user disables the circuit, the control chip U1 activates the fast shutdown function, causing the contactor to disconnect quickly. After triggering the fast shutdown, the fault output terminal FO outputs a low-level trigger signal, turning on the third MOSFET Q3. This draws current from the discharge circuit through the first capacitor C1, with a drawn current of 0.7mA. At this time, the first capacitor C1 discharges until the first MOSFET Q1 operates in the subthreshold region, thereby maintaining the demagnetizing current slope of the contactor coil 200 at (V... ZD1 +2V F +V TH ) / L M This is to reduce the delay in the contactor contacts opening. Where V ZD The clamping voltage of clamping diode ZD1 is 2V. F V is the sum of the forward conduction voltages of the first diode D1 and the current-limiting diode D4. TH L is the threshold voltage of the first MOSFET Q1. M This refers to the inductance of the coil inductive element. After the control chip U1 enters the fast shutdown timing 80ms, the shutdown module 140 stops working, thus saving 0.7mA of current.

[0070] like Figure 8 As shown, in some embodiments of this application, the contactor control circuit 100 may further include a voltage divider detection module 150, which is connected to the voltage detection terminal VT of the control module 120 and the first rectifier unit 1110 to output the voltage detection value obtained according to the first DC high voltage to the voltage detection terminal VT; the control module 120 may also be used to control the output of the drive signal of the output terminal GT according to the voltage detection value; the drive signal may be used to control the controllable switch Q2 on the main circuit where the contactor coil 200 is located.

[0071] In this embodiment, the voltage divider detection module 150 can use a resistor voltage divider circuit to sample the first DC high voltage, thereby obtaining a voltage detection value and outputting it to the voltage detection terminal VT. This allows the control module 120 to control the output of the drive signal based on the received voltage detection value, thereby controlling the controllable switch Q2 to turn on or off. The drive signal can be a pulse width modulation (PWM) signal, and the current in the main circuit can be adjusted by regulating the duty cycle of the drive signal.

[0072] Combination Figure 4As an example, the voltage divider detection module 150 may include a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, and a twenty-fifth resistor R25 connected in series. The connection node of the twentieth resistor R20 and the twenty-fifth resistor R25 is connected to the voltage detection terminal VT. Therefore, the voltage detection value is the voltage divided by the twenty-fifth resistor R25.

[0073] In this embodiment of the application, when the control chip U1 is started, if the voltage detection value is less than the preset voltage threshold, such as 2V, the output terminal GT does not output a drive signal. When the voltage detection value is greater than or equal to the preset voltage threshold, and the drive voltage output by the working voltage output terminal VDD is greater than or equal to the preset start value, such as 11V, the output terminal GT starts to output a drive signal, and the contactor enters the energizing stage.

[0074] When the contactor is working normally, if the voltage detection value is less than the preset undervoltage value, such as 1.4V, and remains less than a certain time, such as 620us, the contactor will enter the undervoltage protection stage. The output terminal GT will be turned off and no longer output drive signals, causing the controllable switch Q2 to open and enter the shutdown stage. At this time, it is possible to choose whether to let the first MOSFET Q1 work in the subthreshold region according to the system status.

[0075] like Figure 9 As shown, in some embodiments of this application, the contactor control circuit 100 may further include a current detection module 160 and a current setting module 170; the current detection module 160 is connected to the main circuit of the contactor coil 200 and the current detection terminal CS of the control module 120, so as to output the detected current detection value on the main circuit where the contactor coil 200 is located to the current detection terminal CS; the current setting module 170 is connected to the current setting terminal of the control module 120; wherein the current setting terminal includes a first setting terminal ISET_H and a second setting terminal ISET_L; the control module 120 may also be used to adjust the duty cycle of the controllable switch Q2 on the main circuit where the contactor coil 200 is located according to the current detection value and the configuration resistor of the current setting module 170, so that the current value of the contactor coil 200 during the pull-in stage and the holding stage is maintained at the corresponding preset current value.

[0076] In this embodiment, the current detection module 160 can be implemented using any existing current detection circuit. The current detection module 160 detects the current in the main circuit and feeds back the detected current value to the control module 120. The control module 120 can then control the duty cycle of the drive signal at the output terminal GT based on the received current detection value and the resistance values ​​of the configured resistors in the current setting module 170, thereby enabling the setting of the peak current during the contactor's engagement and holding phases.

[0077] Combination Figure 4The current detection module 160 includes a current sensing resistor R26, and the current setting module 170 includes a first configuration resistor R27 and a second configuration resistor R28. In this embodiment, the peak currents of the holding and closing stages are set through the first setting terminal ISET_H and the second setting terminal ISET_L. Specifically, by adjusting the resistance values ​​of the configuration resistor between the first setting terminal ISET_H and the second setting terminal ISET_L and the stage segment PGND, the peak current IH of the closing stage and the peak current IL of the holding stage can be set, as shown in the formula:

[0078] IH = (R27 * 0.02) / R26, where the resistance of the first configuration resistor R27 is less than or equal to 250KΩ;

[0079] IL = (R28 * 0.02) / R26, where the resistance of the second configuration resistor R28 is less than or equal to 250KΩ.

[0080] In this embodiment, the output terminal GT outputs a drive signal with an adjustable duty cycle. For example, during the pull-in phase, the maximum pull-in current peak value can be set according to the first configuration resistor R27, at which time a drive signal with a high duty cycle, such as 90%, can be output. During the holding phase, the maximum holding current peak value can be set according to the second configuration resistor R28, and a drive signal with a low duty cycle, such as 50%, can be output, so that the current value of the circuit where the contactor coil 200 is located during the contactor pull-in and holding phases is maintained at the corresponding preset current value.

[0081] Please continue reading. Figure 4 In some embodiments of this application, the contactor control circuit 100 may further include a switching duration setting module, which may include a configuration capacitor C4. One end of the configuration capacitor C4 is connected to the duration setting terminal TR_SET of the control module 120, i.e., the control chip U1, and the other end is connected to the ground terminal PGND, so as to configure the switching duration of the contactor from the energizing stage to the holding stage according to the capacitance value of the configuration capacitor C4.

[0082] In this embodiment, when the detected voltage value is greater than or equal to a preset voltage threshold, such as 2V, and the drive voltage output from the working voltage output terminal VDD is greater than or equal to a preset start value, such as 11V, the control chip U1 can start timing TChange to count the duration of the contactor transitioning from the engaging stage to the holding stage. It is understood that if the contactor enters the undervoltage protection stage during the timing phase, the timing will be reset to zero.

[0083] When the contactor transitions from the pull-in phase to the hold-in phase, the control chip U1 transitions from being active at the first setting terminal ISET_H to being active at the second setting terminal ISET_L. The transition time TChange between the pull-in and hold-in phases can be set via the configuration capacitor C4 connected to the duration setting terminal TR_SET.

[0084] It should be noted that if the control chip U1 is model SCCK0800BEE, it does not have a duration setting terminal TR_SET, and the switching duration is fixed at 80ms.

[0085] If the control chip U1 is model SCCK0800BS, the switching duration TChange can be configured using the following formula: TChange = 40 * C4 * 10 6 In addition, the SCCK0800BS model also has a holding state indication function. When the control chip U1 times the timer TChange, it enters the holding state and after a delay of 20ms, the State pin of the control chip U1 is activated. This State pin is an open-drain output (OD) and needs to be pulled up by an external pull-up resistor.

[0086] The contactor control circuit 100 in this embodiment can adjust the duty cycle of the drive signal at the output terminal GT by presetting the maximum pull-in current and the maximum holding current through the configuration resistors of the first setting terminal ISET_H and the second setting terminal ISET_L of the control chip U1, so that the current value of the circuit in which the coil is located is maintained at the corresponding preset current value during the contactor pull-in stage and the holding stage.

[0087] During the contactor turn-off phase, the current in the coil is rapidly discharged through the turn-off module 140 simultaneously with the open controllable switch Q2. After triggering the rapid turn-off, the third MOSFET Q3 is turned on, the fault output terminal FO of the control chip U1 draws the coil current, and the first capacitor C1 discharges until the first MOSFET Q1 operates in the subthreshold region, thereby increasing the demagnetizing current slope to enable the contactor to turn off rapidly.

[0088] The hardware circuit in this embodiment achieves linear voltage reduction through a step-down unit, enabling the control chip U1 to be used in a higher control voltage range. Furthermore, by simplifying the contactor control circuit, the contactor achieves higher integration, reliability, and stability. It is worth noting that the software portion of this application can be implemented using existing technology, and the scope of protection of this application does not extend to the software solution.

[0089] Based on the contactor control circuit in the above embodiments, and building upon those embodiments, this application also provides a contactor that may include, for example, the contactor control circuit in the above embodiments. Figures 1 to 9 The contactor control circuit corresponds to any embodiment.

[0090] Since the contactor includes the present application, as shown in this application Figures 1 to 9 Corresponding to the contactor control circuit in any embodiment, the present application can be implemented as described above. Figures 1 to 9 For all the beneficial effects that the contactor control circuit can achieve in any embodiment, please refer to the preceding description, which will not be repeated here.

[0091] like Figure 10 As shown, in some embodiments of this application, the contactor may further include a power supply module 310 and a second power supply module 320. The power supply module 310 is connected to the first power supply module 110 and the second power supply module 320 respectively to output AC high voltage to the first power supply module 110 and the second power supply module 320. The second power supply module 320 includes a second rectifier unit 3201, which is connected to the contactor coil 200 to output a second DC high voltage to the contactor coil 200. The second DC high voltage is a voltage signal obtained by rectifying the AC high voltage.

[0092] In this embodiment, the power module 310 can be connected to AC mains power. After processing the AC mains power, it obtains AC high-voltage electricity, which is then supplied to the first power supply module 110 and the second power supply module 320. The second rectifier unit 3201 in the second power supply module 320 can rectify the AC high-voltage electricity into a second DC high-voltage electricity, which is then supplied to the contactor coil 200, energizing the contactor coil 200.

[0093] like Figure 11 As shown, as an example, the power module 310 may include a varistor RV1, a filter capacitor CX1, and differential mode inductors L1 and L2 connected between the live wire terminal J1 and the neutral wire terminal J4; combined with Figure 4 The second rectifier unit 3201 uses the second rectifier bridge BR2. In this embodiment, the power supply of the contactor coil 200 and the power supply of the control chip U1 are output through different rectifier bridges, which can avoid the contactor operation from interfering with the power supply voltage of the control chip U1, ensure the normal operation of the control chip U1, and further improve the reliability of the contactor control circuit.

[0094] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A contactor control circuit, characterized in that, It includes a first power supply module, a control module, a drive module, and a shutdown module; The first power supply module is connected to the power input terminal of the control module to output the power supply voltage to the power input terminal; the power supply voltage is obtained by the first power supply module rectifying and stepping down the AC high voltage. The control module is configured with a fault output terminal connected to the drive module, so as to output a trigger signal to the drive module through the fault output terminal during the contactor turn-off phase. The drive module has a first end connected to the shutdown module and a second end connected to the fault output terminal, and is used to conduct in response to the trigger signal so that the shutdown module and the fault output terminal are electrically connected. The shutdown module is connected to the contactor coil and is used to discharge the current in the contactor coil when it is electrically connected to the fault output terminal, so that the contactor can be quickly shut off.

2. The contactor control circuit according to claim 1, characterized in that, The first power supply module includes a first rectifier unit and a step-down unit; The first rectifier unit is connected to the step-down unit to output a first DC high voltage to the step-down unit; the first DC high voltage is a voltage signal obtained by rectifying the AC high voltage. The step-down unit is connected to the power input terminal to output the supply voltage to the power input terminal; the supply voltage is a voltage signal obtained by stepping down the first DC high voltage.

3. The contactor control circuit according to claim 2, characterized in that, The step-down unit includes a first resistor branch, a first voltage regulator branch, a step-down transistor, and a second resistor branch; The first end of the first resistor branch, the first end of the second resistor branch, and the output terminal of the first rectifier unit are connected. The second end of the first resistor branch, the second end of the first voltage regulator branch, and the base of the step-down transistor are connected. The first end of the first voltage regulator branch is connected to the ground terminal. The collector of the step-down transistor is connected to the second end of the second resistor branch. The emitter of the step-down transistor is connected to the power input terminal.

4. The contactor control circuit according to claim 1, characterized in that, The control module is also configured with a working voltage output terminal. The drive module includes a drive switch unit. The control terminal of the drive switch unit is connected to the working voltage output terminal. The first terminal of the drive switch unit is connected to the shutdown module. The second terminal of the drive switch unit is connected to the fault output terminal.

5. The contactor control circuit according to claim 1, characterized in that, The shutdown module includes a shutdown switch unit, a freewheeling unit, and an energy storage unit; The second end of the freewheeling unit is connected to the first end of the contactor coil, and the first end of the freewheeling unit is connected to the first end of the shut-off switch unit and the first end of the energy storage unit; the second end of the energy storage unit is connected to the control end of the shut-off switch unit and the first end of the drive module; the second end of the shut-off switch unit, the second end of the contactor coil, and the controllable switch on the main circuit where the contactor coil is located are connected.

6. The contactor control circuit according to claim 5, characterized in that, The shutdown module further includes a voltage clamping unit, the first end of which is connected to the control terminal of the shutdown switch unit, and the second end of which is connected to the second end of the shutdown switch unit. The voltage clamping unit includes a current-limiting diode and a clamping diode with their anodes connected to each other. The cathode of the current-limiting diode is connected to the control terminal of the turn-off switch unit, and the cathode of the clamping diode is connected to the second terminal of the turn-off switch unit.

7. The contactor control circuit according to claim 2, characterized in that, The contactor control circuit further includes a voltage divider detection module, which is connected to the voltage detection terminal of the control module and the first rectifier unit to output the voltage detection value obtained based on the first DC high voltage to the voltage detection terminal. The control module is also used to control the output of a drive signal based on the voltage detection value; the drive signal is used to control the controllable switch on the main circuit where the contactor coil is located.

8. The contactor control circuit according to claim 1, characterized in that, The contactor control circuit also includes a current detection module and a current setting module; The current detection module is connected to the main circuit of the contactor coil and the current detection terminal of the control module to output the detected current value on the main circuit where the contactor coil is located to the current detection terminal. The current setting module is connected to the current setting terminal of the control module; The control module is also used to adjust the duty cycle of the controllable switch on the main circuit where the contactor coil is located according to the current detection value and the configuration resistor of the current setting module, so that the current value of the contactor coil during the pull-in stage and the holding stage is maintained at the corresponding preset current value.

9. The contactor control circuit according to claim 1, characterized in that, The contactor control circuit further includes a switching duration setting module, which includes a configuration capacitor. One end of the configuration capacitor is connected to the duration setting terminal of the control module, and the other end is connected to the ground terminal, so as to configure the switching duration of the contactor from the engaging stage to the holding stage according to the capacitance value of the configuration capacitor.

10. A contactor, characterized in that, The contactor control circuit includes any one of claims 1-8.

11. The contactor according to claim 10, characterized in that, The contactor also includes a power supply module and a second power supply module. The power supply module is connected to the first power supply module and the second power supply module respectively to output the AC high voltage to the first power supply module and the second power supply module. The second power supply module includes a second rectifier unit, which is connected to the contactor coil to output a second DC high voltage to the contactor coil; the second DC high voltage is a voltage signal obtained by rectifying the AC high voltage.

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