PWM shunt control circuit and electronic circuit breaker

Abstract

The embodiment of the utility model discloses a PWM shunt control circuit and an electronic circuit breaker. The PWM shunt excitation control circuit comprises a first signal generation module which is connected with a first power supply end and is used for generating a first electric signal; the second signal generation module is connected with the first power supply end and used for generating a second electric signal; the signal overturning adjustment module is connected with the first signal generation module and the second signal generation module, and the signal overturning adjustment module is used for generating a third electric signal according to the NAND result of the first electric signal and the second electric signal; and the output adjusting module is connected between the second power supply end and the grounding end, the control end of the output adjusting module is connected with the signal overturning adjusting module, and the output adjusting module is used for generating a PWM shunt signal according to the third electric signal. According to the technical scheme provided by the embodiment of the invention, the problem that the reliability of the circuit breaker is poor due to heating of the magnetic flux coil when the shunt controller of the existing circuit breaker works for a long time is solved.

Description

Technical Field

[0001] The embodiments of the utility model relate to the field of control technology, and in particular to a PWM shunt control circuit and an electronic circuit breaker. Background Art

[0002] With the development of intelligent technology, people have higher and higher requirements on the shunt controller of circuit breakers.

[0003] Existing shunt controllers mainly have two driving modes: one is a one-time driving mode, that is, the driving signal is output to open the circuit breaker only at the moment of power-on. Subsequently, due to the lack of driving signal, the circuit breaker cannot be driven to open again, posing a safety hazard. The circuit breaker can only be opened normally after power is turned on again, which increases labor costs.

[0004] The other method is to continuously output a drive signal. Although this can solve the problems of the first method, the continuous drive signal will cause the magnetic flux to be in a continuous working state. Long-term operation will cause the magnetic flux coil to heat up severely and eventually be damaged, and the circuit breaker product will lose its shunt function.

[0005] The existing shunt controller of the circuit breaker has the problem of poor reliability of the circuit breaker due to heating of the flux coil when the circuit breaker works for a long time. Utility Model Content

[0006] The present invention provides a PWM shunt control circuit and an electronic circuit breaker to solve the problem that the shunt controller of the existing circuit breaker may heat up the flux coil and cause poor reliability of the circuit breaker when the shunt controller works for a long time.

[0007] In order to achieve the above technical problems, the present invention adopts the following technical solutions:

[0008] The present invention provides a PWM shunt control circuit, comprising:

[0009] a first signal generating module connected to the first power supply terminal and configured to generate a first electrical signal, wherein the first electrical signal has a first level signal in an initial power-on phase and alternately has a second level signal and a first level signal in a first cycle phase; the first level signal and the second level signal are different;

[0010] A second signal generating module is connected to the first power supply terminal and is used to generate a second electrical signal, wherein the second electrical signal has a first level signal in the initial power-on stage and alternately has a second level signal and a first level signal in the second cycle stage;

[0011] a signal inversion adjustment module connected to the first signal generation module and the second signal generation module, the signal inversion adjustment module being configured to generate a third electrical signal according to a negative-AND result of the first electrical signal and the second electrical signal, wherein the period and duty cycle of the third electrical signal are adjustable;

[0012] The output regulating module is connected between the second power supply terminal and the ground terminal. The control terminal of the output regulating module is connected to the signal inversion regulating module. The output regulating module is used to generate a PWM shunt signal according to the third electrical signal.

[0013] Optionally, the first signal generating module includes: a comparison unit, a first voltage regulating unit, and a second voltage regulating unit;

[0014] The first end of the first voltage regulating unit is connected to the first power supply end, the second end of the first voltage regulating unit is connected to the ground end, and the third end of the first voltage regulating unit is connected to the first end of the comparison unit; the first voltage regulating unit is used to adjust the voltage of the first end of the comparison unit;

[0015] A first end of the second voltage regulating unit is connected to the first power supply end, a second end of the second voltage regulating unit is connected to the ground end, a third end of the second voltage regulating unit is connected to the second end of the comparison unit, and a fourth end of the second voltage regulating unit is connected to the first output end of the signal inversion adjustment module; and the output end of the comparison unit is connected to the first input end of the signal inversion adjustment module;

[0016] The second voltage regulating unit is used to adjust the voltage of the second end of the comparison unit according to the level signal output by the first output end of the signal inversion adjustment module;

[0017] The comparison unit is used to generate a first electrical signal according to the difference between the voltage at the first end of the comparison unit and the voltage at the second end of the comparison unit. The first electrical signal is used to be output to the first input end of the signal inversion adjustment module.

[0018] Optionally, the comparison unit includes a comparator; the comparator is configured to generate the first electrical signal according to a difference between a voltage at a non-inverting input terminal and a voltage at an inverting input terminal of the comparator;

[0019] The first voltage regulating unit includes a first resistor and a second resistor; a first end of the first resistor is connected to the first power supply terminal, a second end of the first resistor is connected to the first end of the second resistor and the non-inverting input terminal of the comparator, and a second end of the second resistor is connected to the ground terminal; the first resistor and the second resistor are used to divide the voltage of the first power supply terminal and adjust the voltage of the non-inverting input terminal of the comparator; in the initial stage of power-on, the comparator is used to output a first level signal;

[0020] The second voltage regulating unit includes a first switching tube, a first capacitor, and a third resistor; the first electrode of the first switching tube is connected to the inverting input terminal of the comparator, the first end of the first capacitor, and the first end of the third resistor; the second end of the third resistor is connected to the first power supply terminal; the second end of the first capacitor is connected to the second electrode of the first switching tube and the ground terminal; and the control end of the first switching tube is connected to the first output terminal of the signal inversion adjustment module;

[0021] During a first cycle, the first capacitor is charged by the first power supply terminal through the third resistor, and the charging voltage of the first capacitor is used to adjust the voltage of the inverting input terminal of the comparator; when the voltage of the inverting input terminal of the comparator is greater than or equal to the voltage of the non-inverting input terminal, the comparator outputs a second level signal;

[0022] In the first cycle stage, when the first switch tube is turned on according to the level signal output by the first output terminal of the signal inversion adjustment module, the first capacitor discharges and adjusts the voltage of the inverting input terminal of the comparator; when the voltage of the inverting input terminal of the comparator is less than the voltage of the non-inverting input terminal, the comparator outputs a first level signal.

[0023] Optionally, the second signal generating module includes: a third voltage regulating unit and a trigger unit;

[0024] A first end of the third voltage regulating unit is connected to the first power supply end, a second end of the third voltage regulating unit is connected to the ground end, a third end of the third voltage regulating unit is connected to the first input end of the trigger unit, and a fourth end of the third voltage regulating unit is connected to the second input end of the trigger unit; the third voltage regulating unit is used to adjust the voltage of the second input end of the trigger unit;

[0025] The positive power supply end of the trigger unit is connected to the first power supply end, the negative power supply end of the trigger unit is connected to the ground end, and the output end of the trigger unit is connected to the second input end of the signal inversion adjustment module; the trigger unit is used to generate a second electrical signal according to the voltage of the second input end.

[0026] Optionally, the trigger unit includes a time base chip;

[0027] The third voltage regulating unit includes a fourth resistor, a fifth resistor, a second capacitor, and a first diode;

[0028] A first end of the fourth resistor is connected to the first power supply terminal and the positive power supply terminal of the time base chip, a second end of the fourth resistor is connected to the first end of the fifth resistor, the anode of the first diode, and the first input terminal of the time base chip, a second end of the fifth resistor is connected to the cathode of the first diode, the first end of the second capacitor, and the second input terminal of the time base chip, a second end of the second capacitor is connected to the negative power supply terminal of the time base chip and the ground terminal, and an output terminal of the time base chip is connected to the second input terminal of the signal inversion adjustment module;

[0029] In the initial stage of power-on, the timing chip is used to output a first level signal; in the second cycle stage, when the second capacitor is charged to a level greater than or equal to a first preset threshold, the timing chip is used to output a second level signal, and when the second capacitor is discharged to a level less than or equal to the second preset threshold, the timing chip is used to output the first level signal, and the first preset threshold is greater than the second preset threshold.

[0030] Optional signal inversion adjustment module, including:

[0031] a NAND gate, wherein a first input end of the NAND gate is connected to the output end of the comparator of the first signal generating module, a second input end of the NAND gate is connected to the output end of the trigger unit of the second signal generating module, a first output end of the NAND gate is connected to the control end of the first switch tube of the first signal generating module, and a second output end of the NAND gate is connected to the control end of the second switch tube of the output regulating module;

[0032] The NAND gate is used to output low-level signals at the first output end and the second output end when the first electrical signal and the second electrical signal transmitted at the first input end are both high-level signals; the low-level signal is used to control the first switch tube to turn off and control the second switch tube to turn on.

[0033] Optional, output conditioning module, including:

[0034] a switch unit and a fourth voltage regulating unit;

[0035] The first end of the fourth voltage regulating unit is connected to the second output end of the signal inversion adjustment module;

[0036] The second end of the fourth voltage regulating unit is connected to the first end of the switch unit and the second power supply end, the second end of the fourth voltage regulating unit is connected to the control end of the switch unit, and the second end of the switch unit is used to connect the flux coil and transmit the PWM excitation signal to the flux coil.

[0037] Optionally, the switch unit includes a second switch tube; the fourth voltage regulating unit includes a sixth resistor and a seventh resistor;

[0038] The first end of the sixth resistor is connected to the second output end of the signal inversion adjustment module, the second end of the sixth resistor is connected to the first end of the seventh resistor and the control end of the second switching tube, the second end of the seventh resistor is connected to the first pole of the second switching tube and the second power supply end, and the second pole of the second switching tube is used to connect to the magnetic flux coil and transmit the PWM excitation signal to the magnetic flux coil.

[0039] Optionally, the PWM shunt control circuit further includes: a power supply module;

[0040] The input terminal of the power module is connected to the power input terminal, the first output terminal of the power module is connected to the first power terminal, and the second output terminal of the power module is connected to the second power terminal;

[0041] The power module includes a rectifier unit, a step-down unit and a voltage stabilizing unit. The rectifier unit is connected between the power input end and the high-voltage coil of the step-down unit. The low-voltage coil of the rectifier unit is connected to the second power end and the input end of the voltage stabilizing unit. The output end of the voltage stabilizing unit is connected to the first power end.

[0042] According to another aspect of the present invention, this embodiment provides an electronic circuit breaker, comprising the PWM shunt control circuit of any item of the first aspect.

[0043] The PWM shunt control circuit provided by the present invention generates a first electrical signal through a first signal generation module, generates a second electrical signal through a second signal generation module, and negates the first and second electrical signals through a signal inversion adjustment module, generating a third electrical signal based on the negation of the first and second electrical signals. The output adjustment module then generates a PWM shunt signal based on the third electrical signal. Due to the periodic variation of the high and low levels of the PWM shunt signal, the flux coil of a circuit breaker receiving the PWM shunt signal is periodically energized. This allows the circuit breaker to both implement the shunt function and effectively prevent the flux coil of the circuit breaker from being energized when the PWM shunt signal is low, thereby preventing the flux coil from continuously heating and improving the reliability and safety of the circuit breaker. The PWM shunt control circuit provided by this embodiment addresses the problem of existing circuit breaker shunt controllers, which suffer from flux coil heating and poor circuit breaker reliability when operating for extended periods. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0045] Figure 1 This is a structural diagram of a PWM shunt control circuit provided by an embodiment of the utility model;

[0046] Figure 2 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model;

[0047] Figure 3 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model;

[0048] Figure 4 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model;

[0049] Figure 5 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model;

[0050] Figure 6 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model;

[0051] Figure 7 This is a structural diagram of another PWM shunt control circuit provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0052] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0053] Based on the above technical problems, this embodiment proposes the following solutions:

[0054] Figure 1 This is a schematic diagram of the structure of a PWM shunt control circuit provided by an embodiment of the present utility model. Figure 1 The PWM shunt control circuit provided by the embodiment of the present invention includes: a first signal generating module 1, connected to the first power supply terminal VCC, and used to generate a first electrical signal, the first electrical signal having a first level signal in the initial stage of power-on, and alternating between a second level signal and a first level signal in the first cycle stage; the first level signal and the second level signal are different; a second signal generating module 2, connected to the first power supply terminal VCC, and used to generate a second electrical signal, the second electrical signal having a first level signal in the initial stage of power-on, and alternating between the second level signal and the first level signal in the second cycle stage; a signal inversion adjustment module 3, connected to the first signal generating module 1 and the second signal generating module 2, the signal inversion adjustment module 3 being used to generate a third electrical signal based on a negation result of the first electrical signal and the second electrical signal, the period and duty cycle of the third electrical signal being adjustable; an output adjustment module 4, connected between the second power supply terminal DC and the ground terminal, the control terminal of the output adjustment module 4 being connected to the signal inversion adjustment module 3, and the output adjustment module 4 being used to generate a PWM shunt signal based on the third electrical signal.

[0055] Specifically, the first signal generation module 1 receives a first power signal transmitted from the first power supply terminal VCC, divides the first power signal, and integrates the signal to generate a first electrical signal. The second signal generation module 2 can be an astable circuit. The second signal generation module 2 receives the first power signal transmitted from the first power supply terminal VCC, divides the signal, and performs charging and discharging based on the first power signal. In the absence of a trigger signal, the second electrical signal is output. The second electrical signal switches between high and low levels at a specific frequency, which is determined by the external resistor and capacitor.

[0056] In the initial power-on stage, the first electrical signal generated by the first signal generating module 1 and the second electrical signal generated by the second signal generating module 2 have the same level, both being first level signals.

[0057] The first cycle phase corresponds to the cycle of the first signal generating module 1, and the second cycle phase corresponds to the cycle of the second signal generating module 2. The first cycle phase and the second cycle phase at least partially overlap. During the first cycle phase, the first electrical signal generated by the first signal generating module 1 switches between a first level signal and a second level signal. During the second cycle phase, the second electrical signal generated by the second signal generating module 2 switches between a first level signal and a second level signal.

[0058] The signal inversion adjustment module 3 is connected to the first signal generation module 1 and the second signal generation module 2, respectively. The signal inversion adjustment module 3 is used to perform a negative AND operation on the first electrical signal and the second electrical signal. Based on the negative AND operation result, a third electrical signal is generated. The period and duty cycle of the third electrical signal are adjustable. When the first and second electrical signals have the same level and are both high-level signals, the third electrical signal generated by the signal inversion adjustment module 3 is a low-level signal. When the first and second electrical signals have different levels or are both low-level signals, the third electrical signal generated by the signal inversion adjustment module 3 is a high-level signal.

[0059] The output regulation module 4 is used to control the output regulation module 4 to output a PWM shunt signal according to the third electrical signal received by its control end. The duty cycle of the PWM shunt signal is related to the period between the high-level signal and the low-level signal of the third electrical signal. The duty cycle of the PWM shunt signal can be adjusted by adjusting the time difference between the first-level signal and the second-level signal between the first electrical signal and the second electrical signal. Since the PWM shunt signal includes a high-level signal and a low-level signal. The PWM shunt signal controls the periodic disconnection of the circuit breaker. Due to the periodic changes in the high-level signal and the low-level signal of the PWM shunt signal, the flux coil of the circuit breaker receiving the PWM shunt signal is periodically powered on, so that the circuit breaker can not only realize the shunt function, but also better prevent the flux coil of the circuit breaker from being powered on when the PWM shunt signal is a low-level signal, thereby avoiding continuous heating of the flux coil of the circuit breaker and improving the reliability and safety of the circuit breaker.

[0060] The PWM shunt control circuit provided in this embodiment generates a first electrical signal via a first signal generation module 1, generates a second electrical signal via a second signal generation module 2, and negates the first and second electrical signals via a signal inversion adjustment module 3. A third electrical signal is generated based on the negated result of the AND operation. An output adjustment module 4 then generates a PWM shunt signal based on the third electrical signal. Due to the periodic variation between the high and low levels of the PWM shunt signal, the flux coil of a circuit breaker receiving the PWM shunt signal is periodically energized. This allows the circuit breaker to both implement the shunt function and effectively de-energize the flux coil when the PWM shunt signal is low, thereby preventing the flux coil from continuously heating and improving the reliability and safety of the circuit breaker. The PWM shunt control circuit provided in this embodiment addresses the problem of existing circuit breaker shunt controllers, which can suffer from flux coil heating and poor circuit breaker reliability when operating for extended periods.

[0061] Optional, Figure 2 This is a schematic diagram of another PWM shunt control circuit provided by the present invention. Figure 2The first signal generating module 1 includes: a comparing unit 11, a first voltage regulating unit 12 and a second voltage regulating unit 13; a first end of the first voltage regulating unit 12 is connected to the first power supply terminal VCC, a second end of the first voltage regulating unit 12 is connected to the ground terminal, and a third end of the first voltage regulating unit 12 is connected to the first end of the comparing unit 11; the first voltage regulating unit 12 is used to adjust the voltage of the first end of the comparing unit 11; a first end of the second voltage regulating unit 13 is connected to the first power supply terminal VCC, a second end of the second voltage regulating unit 13 is connected to the ground terminal, and a third end of the second voltage regulating unit 13 is connected to the first end of the comparing unit 11 The second end is connected, the fourth end of the second voltage regulating unit 13 is connected to the first output end OUT1 of the signal flip adjustment module 3; the output end of the comparison unit 11 is connected to the first input end of the signal flip adjustment module 3; the second voltage regulating unit 13 is used to adjust the voltage of the second end of the comparison unit 11 according to the level signal output by the first output end OUT1 of the signal flip adjustment module 3; the comparison unit 11 is used to generate a first electrical signal according to the difference between the voltage of the first end of the comparison unit 11 and the voltage of the second end of the comparison unit 11, and the first electrical signal is used to output to the first input end of the signal flip adjustment module 3.

[0062] Specifically, the first voltage regulating unit 12 can regulate the voltage at the first end of the comparison unit 11 , and the second voltage regulating unit 13 can regulate the voltage at the second end of the comparison unit 11 .

[0063] During the initial power-on phase, the first voltage regulating unit 12 increases the voltage at the first terminal of the comparison unit 11, while the second voltage regulating unit 13 is inactive, so that the voltage at the second terminal of the comparison unit 11 is lower than the voltage at the first terminal thereof, and the first electrical signal output by the comparison unit 11 is a first-level signal. For example, the first-level signal may be a high-level signal.

[0064] During the first cycle phase, the voltage output by the first voltage regulating unit 12 to the first terminal of the comparison unit 11 remains unchanged. The second voltage regulating unit 13 increases or decreases the voltage at the second terminal of the comparison unit 11 through the process of charging and discharging cycles. When the second voltage regulating unit 13 adjusts the voltage at the second terminal of the comparison unit 11 to a voltage higher than the voltage at the first terminal of the comparison unit 11, the first electrical signal output from the output terminal of the comparison unit 11 is a second level signal. When the fourth terminal of the second voltage regulating unit 13 receives the second level signal from the first output terminal OUT1 of the signal inversion adjustment module 3, the second voltage regulating unit 13 adjusts the voltage at the second terminal of the comparison unit 11 to a voltage lower than the voltage at the first terminal of the comparison unit 11, and the first electrical signal output from the output terminal of the comparison unit 11 is inverted to the first level signal.

[0065] Optionally, based on the above embodiments, continue to refer to Figure 2The comparison unit 11 includes a comparator U2; the comparator U2 is used to generate a first electrical signal according to the difference between the voltage at the non-inverting input terminal and the voltage at the inverting input terminal of the comparator U2; the first voltage regulating unit 12 includes a first resistor R1 and a second resistor R4; the first end of the first resistor R1 is connected to the first power supply terminal VCC, the second end of the first resistor R1 is connected to the first end of the second resistor R4 and the non-inverting input terminal of the comparator U2, and the second end of the second resistor R4 is connected to the ground terminal; the first resistor R1 and the second resistor R4 are used to divide the voltage of the first power supply terminal VCC and adjust the voltage of the non-inverting input terminal of the comparator U2; in the initial stage of power-on, the comparator U2 is used to output a first level signal.

[0066] The second voltage regulating unit 13 includes a first switching tube Q1, a first capacitor C5, and a third resistor R2; the first electrode of the first switching tube Q1 is connected to the inverting input terminal of the comparator U2, the first end of the first capacitor C5, and the first end of the third resistor R2, the second end of the third resistor R2 is connected to the first power supply terminal VCC, the second end of the first capacitor C5 is connected to the second electrode of the first switching tube Q1 and the ground terminal, and the control end of the first switching tube Q1 is connected to the first output terminal OUT1 of the signal inversion adjustment module 3.

[0067] In the first cycle phase, the first capacitor C5 is used to be charged by the first power supply terminal VCC through the third resistor R2, and the charging voltage of the first capacitor C5 is used to adjust the voltage of the inverting input terminal of the comparator U2; when the voltage of the inverting input terminal of the comparator U2 is greater than or equal to the voltage of the non-inverting input terminal, the comparator U2 outputs a second level signal; in the first cycle phase, when the first switch tube Q1 is turned on according to the level signal output by the first output terminal OUT1 of the signal inversion adjustment module 3, the first capacitor C5 is discharged and the voltage of the inverting input terminal of the comparator U2 is adjusted; when the voltage of the inverting input terminal of the comparator U2 is less than the voltage of the non-inverting input terminal, the comparator U2 outputs a first level signal.

[0068] Specifically, the first cycle cycle stage refers to the level flip cycle of the first electrical signal output by the first signal generating module 1. The voltage of the non-inverting input terminal of the comparator U2 can be adjusted by adjusting the resistance values ​​of the first resistor R1 and the second resistor R4 of the second voltage regulating unit 13. The voltage transmitted by the first power supply terminal VCC can be DC 5V. The first capacitor C5 can be charged through the first power supply terminal VCC through the third resistor R2. When the first capacitor C5 is charged to reach the voltage of the non-inverting input terminal, the voltage of the inverting input terminal of the comparator U2 is higher than the voltage of the non-inverting input terminal, and the comparator U2 will output a second level signal, that is, a low level signal.

[0069] When the control terminal of the first switch tube Q1 is turned on according to the level signal output by the first output terminal OUT1 of the signal inversion adjustment module 3, the first electrode and the second electrode of the first switch tube Q1 are turned on. The turned-on first switch tube Q1 discharges the first capacitor C5, causing the voltage at the inverting input terminal of the comparator U2 to decrease. When the voltage at the inverting input terminal of the comparator U2 is lower than the voltage at the non-inverting input terminal, the first electrical signal output by the comparator U2 is inverted to the first level signal, i.e., a high level signal.

[0070] Optional, Figure 3 This is a schematic diagram of the structure of another PWM shunt control circuit provided by the embodiment of the present utility model. Figure 3 The second signal generating module 2 includes: a third voltage regulating unit 21 and a trigger unit 22; a first end of the third voltage regulating unit 21 is connected to the first power supply end VCC, a second end of the third voltage regulating unit 21 is connected to the ground end, a third end of the third voltage regulating unit 21 is connected to the first input end of the trigger unit 22, and a fourth end of the third voltage regulating unit 21 is connected to the second input end of the trigger unit 22; the third voltage regulating unit 21 is used to adjust the voltage of the second input end of the trigger unit 22; the positive power supply end of the trigger unit 22 is connected to the first power supply end VCC, the negative power supply end of the trigger unit 22 is connected to the ground end, and the output end of the trigger unit 22 is connected to the second input end of the signal inversion adjustment module 3; the trigger unit 22 is used to generate a second electrical signal according to the voltage of the second input end.

[0071] Specifically, the second cycle phase refers to the level flip cycle of the second electrical signal output by the second signal generating module 2. During the initial power-on phase, the third voltage regulating unit 21 can adjust the voltage at the input end of the trigger unit 22 so that the second electrical signal output by the trigger unit 22 is a first level signal, i.e., a high level signal. This configuration allows the first electrical signal and the second electrical signal to be at the same level during the initial power-on phase, so that the output end of the signal flip adjustment module 3 can output a low level signal, thereby controlling the output adjustment module 4 to conduct and output the initial shunt signal. The initial shunt signal can energize the flux coil of the circuit breaker, causing the circuit breaker to successfully trip. During the second cycle phase, when the third voltage regulating unit 21 is charged to a level greater than or equal to the first preset threshold, the trigger unit 22 is configured to output a second level signal, i.e., a low level signal. When the third voltage regulating unit 21 is discharged to a level less than or equal to the second preset threshold, the trigger unit 22 outputs a first level signal, i.e., a high level signal.

[0072] Optionally, based on the above embodiments, continue to refer to Figure 3, the trigger unit 22 includes a time base chip U4; the third voltage regulating unit 21 includes a fourth resistor R10, a fifth resistor R11, a second capacitor C10, and a first diode D6; the first end of the fourth resistor R10 is connected to the first power supply terminal VCC and the positive power supply terminal of the time base chip U4, the second end of the fourth resistor R10 is connected to the first end of the fifth resistor R11, the anode of the first diode D6, and the first input terminal of the time base chip U4, the second end of the fifth resistor R11 is connected to the cathode of the first diode D6, the first end of the second capacitor C10, and the second input terminal of the time base chip U4 The first terminal of the timing chip U4 is connected to the negative power supply terminal and the ground terminal of the timing chip U4, and the output terminal of the timing chip U4 is connected to the second input terminal of the signal flip adjustment module 3; in the initial stage of power-on, the timing chip U4 is used to output a first level signal; in the second cycle stage, when the second capacitor C10 is charged to a value greater than or equal to the first preset threshold, the timing chip U4 is used to output a second level signal, and when the second capacitor C10 is discharged to a value less than or equal to the second preset threshold, the timing chip U4 is used to output the first level signal, and the first preset threshold is greater than the second preset threshold.

[0073] Specifically, the first preset threshold may be set to 2 / 3 VCC, and the second preset threshold may be set to 1 / 3 VCC.

[0074] During the initial power-up phase, the voltage of the second capacitor C10 cannot change suddenly, so the input terminal of the time-base chip U4 is a low-level signal, and the output terminal of the clock signal outputs a high-level signal. During the second cycle phase, when the second capacitor C10 is charged to a voltage greater than or equal to 2 / 3 VCC through the fourth resistor R10 and the first diode D6, the level signal output by the output terminal of the time-base chip U4 flips to the second level signal, i.e., a low-level signal. Then, when the second capacitor C10 is discharged to a voltage less than or equal to 1 / 3 VCC through the fifth resistor R11, the level signal output by the output terminal of the time-base chip U4 flips again, i.e., outputs the first level signal, i.e., a high-level signal. After that, the second capacitor C10 is charged and discharged again, and the cycle continues.

[0075] Optional, Figure 4 This is a schematic diagram of the structure of another PWM shunt control circuit provided by the embodiment of the present utility model. Figure 4 Based on the above embodiments, continue to refer to Figure 3The signal inversion adjustment module 3 includes: a NAND gate 31, a first input terminal INE of the NAND gate 31 is connected to the output terminal of the comparator U2 of the first signal generating module 1, a second input terminal IND of the NAND gate 31 is connected to the output terminal of the trigger unit 22 of the second signal generating module 2, a first output terminal OUT1 of the NAND gate 31 is connected to the control terminal of the first switch tube Q1 of the first signal generating module 1, and a second output terminal OUT2 of the NAND gate 31 is connected to the control terminal of the second switch tube of the output adjustment module 4; the NAND gate 31 is used to output low-level signals at the first output terminal OUT1 and the second output terminal OUT2 when the first electrical signal and the second electrical signal transmitted at the first input terminal are both high-level signals; the low-level signals are used to control the first switch tube Q1 to be turned off and control the second switch tube to be turned on.

[0076] Specifically, NAND gate 31 receives a first electrical signal input from a first input terminal and a second electrical signal input from a second input terminal, performs an AND operation on the first and second electrical signals, and then inverts the result. When both the first and second electrical signals are at a first level (i.e., a high level), NAND gate 31 outputs a low level. When one or both of the first and second signals are at a second level (i.e., a low level), NAND gate 31 outputs a high level.

[0077] The low-level signal output by the NAND gate 31 is output through the first output terminal OUT1 and the second output terminal OUT2. The first output terminal OUT1 is connected to the control terminal of the first switch transistor Q1 of the first signal generating module. The low-level signal controls the first switch transistor Q1 to conduct, discharging the first capacitor C5, making the voltage at the inverting input terminal of the comparator U2 lower than the voltage at the non-inverting input terminal of the comparator U2, causing the first-level signal to flip, that is, output a high-level signal.

[0078] The low level signal output by the NAND gate 31 is transmitted to the second switch tube of the output regulation module 4 through the second output terminal OUT2. When the second switch tube of the output regulation module 4 is turned on, the second power supply voltage transmitted by the second power supply terminal DC is output to the output terminal Vout.

[0079] Optional, Figure 5 This is a schematic diagram of the structure of another PWM shunt control circuit provided by the embodiment of the present utility model. Figure 5 The output regulation module 4 may include: a switch unit 41 and a fourth voltage regulation unit 42; a first end of the fourth voltage regulation unit 42 is connected to the second output end OUT2 of the signal inversion adjustment module 3; a second end of the fourth voltage regulation unit 42 is connected to the first end of the switch unit 41 and the second power supply end DC, a second end of the fourth voltage regulation unit 42 is connected to the control end of the switch unit 41, and a second end of the switch unit 41 is used to connect to the flux coil and transmit a PWM shunt signal to the flux coil.

[0080] Specifically, the voltage of the second power supply terminal DC is higher than the voltage of the first power supply terminal VCC. For example, the voltage of the first power supply terminal VCC can be 5V DC, and the voltage of the second power supply terminal DC can be 12V DC. The fourth voltage regulating unit 42 can function as a current limiter to prevent excessive signals from damaging the switch unit 41. When the switch unit 41 is turned on in response to the low-level signal output by the NAND gate 31, the output terminal is connected to the second power supply terminal DC to output a PWM shunt signal to the flux coil of the circuit breaker.

[0081] Optionally, based on the above embodiments, continue to refer to Figure 5 The switch unit 41 includes a second switch tube Q2; the fourth voltage regulating unit 42 includes a sixth resistor R8 and a seventh resistor R9; a first end of the sixth resistor R8 is connected to the second output end OUT2 of the signal inversion adjustment module 3, a second end of the sixth resistor R8 is connected to the first end of the seventh resistor R9 and the control end of the second switch tube Q2, a second end of the seventh resistor R9 is connected to the first electrode of the second switch tube Q2 and the second power supply end DC, and the second electrode of the second switch tube Q2 is used to connect to the magnetic flux coil and transmit the PWM shunt signal to the magnetic flux coil.

[0082] Specifically, the duty cycle of the PWM shunt signal ranges from 1% to 100%. The duty cycle of the PWM shunt signal can be set to a range of 5% to 25%, including the range of 1% to 25%. This configuration ensures the output power of the PWM shunt control circuit while controlling the temperature within a preset range, preventing heating of the circuit breaker's flux coil and improving the circuit breaker's reliability and safety. The duty cycle of the PWM shunt signal can be adjusted by the resistance of the third resistor R2 and the capacitance of the first capacitor C5.

[0083] Optional, Figure 6 This is a schematic diagram of the structure of another PWM shunt control circuit provided by the embodiment of the present utility model. Figure 6 The PWM shunt control circuit further includes: a power supply module 5; an input terminal of the power supply module 5 is connected to the power supply input terminal, a first output terminal of the power supply module 5 is connected to the first power supply terminal VCC, and a second output terminal of the power supply module 5 is connected to the second power supply terminal DC; the power supply module 5 includes a rectifier unit 51, a step-down unit 52, and a voltage stabilizing unit 53. The rectifier unit 51 is connected between the power supply input terminal AC and the high-voltage coil of the step-down unit 52, the low-voltage coil of the rectifier unit 51 is connected to the second power supply terminal DC and the input terminal of the voltage stabilizing unit 53, and the output terminal of the voltage stabilizing unit 53 is connected to the first power supply terminal VCC. Optionally, the input voltage of the power supply input terminal AC is greater than or equal to AC110V and less than or equal to AC380V.

[0084] Specifically, the voltage inputted by the power input terminal includes an AC input voltage such as AC 110V, 220V or 380V.

[0085] Figure 7 This is a schematic diagram of the structure of another PWM shunt control circuit provided by the embodiment of the present utility model. Figure 7 The power module 5 absorbs the AC input through the varistor and then steps down the voltage through the full-wave rectifier circuit to generate a DC voltage VPP. After passing through the flyback switching power supply with isolated PSR feedback, the secondary output DC 12V voltage is output to the second power supply terminal DC. After stepping down, it generates a DC 5V voltage, which is output to the first power supply terminal VCC to power the PWM shunt control circuit.

[0086] It should be noted that Figure 7 This is an optional implementation of the power module 5 provided in this embodiment and is not limited here. Figure 7 The power module 5 outputs a rectified DC voltage VPP, which is output as 12V at the second power terminal DC after passing through the step-down unit 52. The second power terminal DC is stepped down to 5V at the first power terminal VCC by the voltage stabilizing unit 53. Figure 7 The AC ground terminal AGND, the DC ground terminal GND, and the transformer T1 are exemplarily shown in FIG. 1 , and no limitation is given herein.

[0087] This embodiment provides an electronic circuit breaker, including the PWM shunt control circuit provided by any of the above embodiments, and has the beneficial effects of the PWM shunt control circuit provided by any of the above embodiments, which will not be described in detail here.

[0088] Note that the above are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions are possible for those skilled in the art without departing from the scope of protection of the present invention. Therefore, while the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A PWM shunt control circuit, characterized in that: include: A first signal generating module is connected to the first power supply terminal and is used to generate a first electrical signal, wherein the first electrical signal has a first level signal in an initial power-on phase and alternately has a second level signal and a first level signal in a first cycle phase; The first level signal and the second level signal are different; a second signal generating module, connected to the first power supply terminal, and configured to generate a second electrical signal, wherein the second electrical signal has a first level signal in an initial power-on phase, and alternately has the second level signal and the first level signal in a second cycle phase; a signal inversion adjustment module connected to the first signal generation module and the second signal generation module, the signal inversion adjustment module being configured to generate a third electrical signal according to a negation result of the first electrical signal and the second electrical signal, wherein the period and duty cycle of the third electrical signal are adjustable; An output regulating module is connected between the second power supply terminal and the ground terminal. The control terminal of the output regulating module is connected to the signal inversion regulating module. The output regulating module is used to generate a PWM shunt signal according to the third electrical signal.

2. The PWM shunt control circuit according to claim 1, characterized in that: The first signal generating module includes: a comparison unit, a first voltage regulating unit and a second voltage regulating unit; The first end of the first voltage regulating unit is connected to the first power supply end, the second end of the first voltage regulating unit is connected to the ground end, and the third end of the first voltage regulating unit is connected to the first end of the comparison unit; the first voltage regulating unit is used to adjust the voltage of the first end of the comparison unit; A first end of the second voltage regulating unit is connected to the first power supply end, a second end of the second voltage regulating unit is connected to the ground end, a third end of the second voltage regulating unit is connected to the second end of the comparison unit, and a fourth end of the second voltage regulating unit is connected to the first output end of the signal inversion adjustment module; and the output end of the comparison unit is connected to the first input end of the signal inversion adjustment module; The second voltage regulating unit is configured to regulate the voltage of the second terminal of the comparing unit according to the level signal outputted by the first output terminal of the signal inversion adjusting module; The comparison unit is used to generate the first electrical signal according to the difference between the voltage at the first end of the comparison unit and the voltage at the second end of the comparison unit, and the first electrical signal is used to be output to the first input end of the signal inversion adjustment module.

3. The PWM shunt control circuit according to claim 2, characterized in that: The comparison unit includes a comparator; the comparator is used to generate a first electrical signal according to the difference between the voltage at the non-inverting input terminal and the voltage at the inverting input terminal of the comparator; The first voltage regulating unit includes a first resistor and a second resistor; a first end of the first resistor is connected to the first power supply terminal, a second end of the first resistor is connected to the first end of the second resistor and the non-inverting input terminal of the comparator, and a second end of the second resistor is connected to the ground terminal; the first resistor and the second resistor are used to divide the voltage of the first power supply terminal and adjust the voltage of the non-inverting input terminal of the comparator; in the initial power-on stage, the comparator is used to output a first level signal; The second voltage regulating unit includes a first switching tube, a first capacitor, and a third resistor; the first electrode of the first switching tube is connected to the inverting input terminal of the comparator, the first end of the first capacitor, and the first end of the third resistor, the second end of the third resistor is connected to the first power supply terminal, the second end of the first capacitor is connected to the second electrode of the first switching tube and the ground terminal, and the control end of the first switching tube is connected to the first output end of the signal inversion adjustment module; In a first cycle phase, the first capacitor is used to be charged by the first power supply terminal through the third resistor, and the charging voltage of the first capacitor is used to adjust the voltage of the inverting input terminal of the comparator; when the voltage of the inverting input terminal of the comparator is greater than or equal to the voltage of the non-inverting input terminal, the comparator outputs a second level signal; In the first cycle stage, when the first switching tube is turned on according to the level signal output by the first output end of the signal inversion adjustment module, the first capacitor discharges and adjusts the voltage of the inverting input end of the comparator; when the voltage of the inverting input end of the comparator is less than the voltage of the non-inverting input end, the comparator outputs a first level signal.

4. The PWM shunt control circuit according to claim 1, characterized in that: The second signal generating module includes: a third voltage regulating unit and a trigger unit; A first end of the third voltage regulating unit is connected to the first power supply end, a second end of the third voltage regulating unit is connected to the ground end, a third end of the third voltage regulating unit is connected to the first input end of the trigger unit, and a fourth end of the third voltage regulating unit is connected to the second input end of the trigger unit; the third voltage regulating unit is used to adjust the voltage of the second input end of the trigger unit; The positive power supply end of the trigger unit is connected to the first power supply end, the negative power supply end of the trigger unit is connected to the ground end, and the output end of the trigger unit is connected to the second input end of the signal flip adjustment module; the trigger unit is used to generate the second electrical signal according to the voltage of the second input end.

5. The PWM shunt control circuit according to claim 4, characterized in that: The trigger unit includes a time base chip; The third voltage regulating unit includes a fourth resistor, a fifth resistor, a second capacitor, and a first diode; A first end of the fourth resistor is connected to the first power supply terminal and the positive power supply terminal of the time base chip, a second end of the fourth resistor is connected to the first end of the fifth resistor, the anode of the first diode, and the first input terminal of the time base chip, a second end of the fifth resistor is connected to the cathode of the first diode, the first end of the second capacitor, and the second input terminal of the time base chip, a second end of the second capacitor is connected to the negative power supply terminal of the time base chip and the ground terminal, and an output terminal of the time base chip is connected to the second input terminal of the signal inversion adjustment module; In the initial stage of power-on, the time base chip is used to output a first level signal; In the second cycle stage, when the second capacitor is charged to a level greater than or equal to a first preset threshold, the timing chip is used to output a second level signal; when the second capacitor is discharged to a level less than or equal to a second preset threshold, the timing chip is used to output a first level signal, and the first preset threshold is greater than the second preset threshold.

6. The PWM shunt control circuit according to claim 1, characterized in that: The signal inversion adjustment module includes: a NAND gate, wherein a first input end of the NAND gate is connected to the output end of the comparator of the first signal generating module, a second input end of the NAND gate is connected to the output end of the trigger unit of the second signal generating module, a first output end of the NAND gate is connected to the control end of the first switch tube of the first signal generating module, and a second output end of the NAND gate is connected to the control end of the second switch tube of the output regulating module; The NAND gate is used to output low-level signals at both the first output end and the second output end when the first electrical signal and the second electrical signal transmitted at the first input end are both high-level signals; the low-level signal is used to control the first switch tube to turn off and control the second switch tube to turn on.

7. The PWM shunt control circuit according to claim 1, characterized in that: The output regulation module includes: a switch unit and a fourth voltage regulating unit; The first end of the fourth voltage regulating unit is connected to the second output end of the signal inversion adjustment module; The second end of the fourth voltage regulating unit is connected to the first end of the switch unit and the second power supply end, the second end of the fourth voltage regulating unit is connected to the control end of the switch unit, and the second end of the switch unit is used to connect the flux coil and transmit the PWM excitation signal to the flux coil.

8. The PWM shunt control circuit according to claim 7, characterized in that: The switch unit includes a second switch tube; the fourth voltage regulating unit includes a sixth resistor and a seventh resistor; The first end of the sixth resistor is connected to the second output end of the signal inversion adjustment module, the second end of the sixth resistor is connected to the first end of the seventh resistor and the control end of the second switch tube, the second end of the seventh resistor is connected to the first pole of the second switch tube and the second power supply end, and the second pole of the second switch tube is used to connect to the magnetic flux coil and transmit the PWM excitation signal to the magnetic flux coil.

9. The PWM shunt control circuit according to any one of claims 1 to 8, characterized in that: The PWM shunt control circuit further includes: a power supply module; The input end of the power module is connected to the power input end, the first output end of the power module is connected to the first power end, and the second output end of the power module is connected to the second power end; The power module includes a rectifier unit, a step-down unit and a voltage stabilizing unit. The rectifier unit is connected between the power input end and the high-voltage coil of the step-down unit, the low-voltage coil of the rectifier unit is connected to the second power end and the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is connected to the first power end.

10. An electronic circuit breaker, characterized in that: The invention comprises the PWM shunt control circuit according to any one of claims 1 to 9.

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