Safety power utilization initiative protection intelligent control cabinet

Abstract

This invention discloses an intelligent control cabinet for active protection of safe electricity use, including an overcurrent detection module, a control module, and a switch protection module. The overcurrent detection module includes a current acquisition circuit and a signal processing circuit. The current acquisition circuit detects the current in the main power supply circuit and sends the detection signal to the signal processing circuit for processing. The signal processing circuit uses a differential amplifier noise suppression unit to effectively eliminate interference from harmful signals in the current acquisition process, thereby improving measurement accuracy. Negative feedback adjustment is performed through a feedback adjustment unit to effectively suppress fluctuations in the amplitude of the detection signal. Then, a signal output stabilization unit is used to stabilize the output signal of the differential amplifier noise suppression unit, effectively protecting the control module and improving the stability of system control. This makes the entire system more accurate in monitoring short-circuit faults and more reliable in control, effectively preventing electrical fires.

Description

Technical Field

[0001] This invention relates to the field of safe electrical equipment technology, and in particular to an intelligent control cabinet for active protection of safe electrical use. Background Technology

[0002] In electrical circuits, a short circuit occurs when current bypasses the electrical equipment and directly forms a loop due to various reasons causing connections or contact. When a short circuit occurs, the current in the circuit increases several times or even tens of times the normal value, and the heat generated is proportional to the square of the current, causing the temperature to rise rapidly, far exceeding the permissible range. If the temperature reaches the ignition temperature of flammable materials, combustion occurs, leading to a fire. Electrical fires are caused by aging wiring, leakage, high-voltage breakdown, high temperatures, etc. Timely detection of these hidden dangers and implementation of preventative measures are crucial for effectively controlling electrical fires.

[0003] Existing electrical safety protection devices for monitoring electrical short-circuit fires typically consist of a current transformer, a signal processing module, and a control module. For example, Chinese invention patent application number 201610600030.5 discloses a residual current transformer fault detection circuit and an electrical fire detector. This includes a residual current fault detection circuit connected to a main control module. A signal processing module connected to the residual current transformer emits an instantaneous pulse voltage, which is applied to the transformer's connection line to monitor the line current. The signal is amplified through a signal sampling and amplification circuit, and the MCU processes the ADC voltage to detect faults in the residual current transformer connection. This technical solution uses a current transformer to sample the current and only uses a differential operational amplifier U3 to amplify the sampled signal. This signal processing method is prone to nonlinear interference and signal distortion during short-circuit current monitoring, resulting in large measurement errors and failing to effectively guarantee the accuracy of fault detection.

[0004] For example, Chinese invention patent application number 201810195425.0 discloses a short-circuit protection circuit, including a voltage regulator module, a short-circuit detection module, and a control module. The short-circuit detection module includes a protection voltage sampling unit, a reference voltage generation unit, and a voltage comparison unit. The voltage comparison unit uses the comparator principle to determine whether a short circuit has occurred. Although this technical solution simplifies the circuit structure, it has high requirements for the stability of the internal circuit of the detection circuit. When a short circuit occurs, it usually causes a large impact on the internal circuit. In addition, fluctuations in the power supply network and external interference will interfere with the stability of the detection signal, making it impossible to guarantee the stability of the system control.

[0005] Therefore, the present invention provides a new solution to this problem. Summary of the Invention

[0006] In view of the above situation and to overcome the defects of the prior art, the purpose of this invention is to provide an intelligent control cabinet for active protection of safe electricity use.

[0007] The technical solution is: a smart control cabinet for active protection of safe electricity use, including an overcurrent detection module, a control module and a switch protection module. The overcurrent detection module includes a current acquisition circuit and a signal processing circuit. The current acquisition circuit is used to detect the magnitude of the current in the main power supply circuit and send the detection signal to the signal processing circuit for processing.

[0008] The signal processing circuit includes a differential amplifier noise suppression unit, a feedback adjustment unit, and a signal output stabilization unit. The differential amplifier noise suppression unit includes a differential amplifier for amplifying and enhancing the detection signal, and a combined adjustment transistor for following and adjusting the output signal of the differential amplifier. A band-stop filter for eliminating harmful noise in the main power supply circuit is also provided between the differential amplifier and the combined adjustment transistor. The feedback adjustment unit is used to provide feedback on the output signal of the differential amplifier noise suppression unit and suppress fluctuations generated when the band-stop filter is working. The signal output stabilization unit is used to stabilize the detection signal processed by the feedback adjustment unit before sending it to the control module.

[0009] The control module changes the on / off state of the main power supply circuit by controlling the switch protection module.

[0010] Preferably, the current acquisition circuit includes a current transformer CT1 and an operational amplifier AR1. One end of the current transformer CT1 is connected to one end of a resistor R1 and is connected to the non-inverting input of the operational amplifier AR1 through a resistor R2. The other end of the current transformer CT1 is connected to the other end of a resistor R2 and is connected to the inverting input of the operational amplifier AR1 through a resistor R3. The output of the operational amplifier AR1 is connected to an adjustable resistor RL1, one end of a capacitor C1, and the input of the signal processing circuit. The other end of the capacitor C1 is connected to the other end of the adjustable resistor RL1 and the inverting input of the operational amplifier AR1 through a resistor R4.

[0011] Preferably, the differential amplifier includes operational amplifier AR2 and operational amplifier AR3. The output terminal of operational amplifier AR2 is connected to the input terminal of the combined regulating transistor. The non-inverting input terminal of operational amplifier AR2 is connected to the non-inverting input terminal of operational amplifier AR3. The inverting input terminal and output terminal of operational amplifier AR3 are connected to the input terminal of the band-stop filter. The output terminal of the band-stop filter is connected to the control terminal of the combined regulating transistor.

[0012] Preferably, the combined regulating transistor includes transistors VT1 and VT2. The collector of transistor VT1 is connected to one end of resistors R7 and R8. The other end of resistor R7 is connected to the output terminal of operational amplifier AR2. The other end of resistor R8 is connected to the emitter of transistor VT2 and grounded through capacitor C4. The collector of transistor VT2 is connected to the base of transistor VT1. The emitter of transistor VT1 is connected to the inverting input terminal of operational amplifier AR2 through parallel resistor R6 and capacitor C3. The base of transistor VT2 is connected to the output terminal of the band-stop filter through resistor R11.

[0013] Preferably, the band-stop filter includes resistors R9 and R10, inductors L2 and L3, and capacitors C5 and C6. One end of resistor R9 is connected to the output terminal of operational amplifier AR3, and the other end of resistor R9 is connected to one end of inductor L3 and the control terminal of the combined regulating transistor through inductor L2 and capacitor C5 in parallel. The other end of inductor L3 is grounded through capacitor C6 and resistor R10 in parallel.

[0014] Preferably, an LC filter is further provided between the differential amplifier and the operational amplifier AR1. The LC filter includes an inductor L1, one end of which is connected to the output terminal of the operational amplifier AR1, and the other end of which is grounded through a parallel resistor R5 and a capacitor C2, and connected to the inverting input terminal of the operational amplifier AR2 through a diode VD1.

[0015] Preferably, the input terminal of the differential amplifier is further provided with a bias circuit, which includes a potentiometer RP1. One end of the potentiometer RP1 is connected to a -5V power supply through a resistor R18 and grounded through a resistor R19. The other end of the potentiometer RP1 is connected to a +5V power supply through a resistor R21 and grounded through a resistor R20. The adjustment terminal of the potentiometer RP1 is connected to the inverting input terminal of the operational amplifier AR2.

[0016] Preferably, the feedback adjustment unit includes MOSFET Q1 and MOSFET Q2. The source of MOSFET Q1 is connected to the base of transistor VT2. The gate of MOSFET Q1 is connected to the emitter of transistor VT1 through resistor R12. The drain of MOSFET Q1 is connected to the cathode of Zener diode DZ1. The anode of Zener diode DZ1 is connected to the gate of MOSFET Q2 and grounded through parallel resistor R13 and capacitor C7. The source of MOSFET Q2 is connected to the output terminal of the band-stop filter through diode VD2. The drain of MOSFET Q2 is grounded.

[0017] Preferably, the signal output stabilization unit includes transistors VT3 and VT4. The collector of transistor VT3 is connected to one end of capacitor C8 and the cathode of Zener diode DZ2, and is connected to the output terminal of the differential amplifier noise suppression unit through resistor R14. The other end of capacitor C8 is connected to the base of transistor VT3 and the collector of transistor VT4 through the anode of Zener diode DZ1. The emitter of transistor VT3 is connected to resistor R15, one end of potentiometer RP2, and the control module. The emitter of transistor VT4 is connected to resistor R16, one end of capacitor C9, and the other end of resistor R15. The other end of resistor R16 is connected to the drain of MOSFET Q1. The other end of capacitor C9 is grounded. The base-drain potentiometer RP2 of transistor VT4 is the adjustment terminal. The other end of potentiometer RP2 is grounded through resistor R17.

[0018] Preferably, the control module includes a microcontroller and an external switch drive circuit, the switch protection module is a power distribution circuit breaker, and the microcontroller controls the operation of the power distribution circuit breaker by driving the external switch drive circuit.

[0019] The beneficial effects of the present invention through the above technical solutions are as follows:

[0020] 1. The intelligent control cabinet of this invention forms an active power protection system by setting up an overcurrent detection module, a control module, and a switch protection module inside the cabinet. The overcurrent detection module consists of a current acquisition circuit and a signal processing circuit. The current acquisition circuit acquires the current in the main power supply circuit and sends the current acquisition signal to the signal processing circuit for conditioning. The differential amplification principle is used to eliminate interference from external environmental factors. At the same time, a combination transistor is used as a follower amplification component to quickly increase the amplitude of the attenuated signal, and a band-stop filter network is used to suppress and attenuate the fluctuation frequency in the power supply network, thereby making the entire system more accurate in monitoring short-circuit faults.

[0021] 2. By setting a feedback adjustment unit to perform negative feedback adjustment on the band-stop filtered signal, the amplitude fluctuation of the detection signal is effectively suppressed. Then, a signal output stabilization unit is used to stabilize the output signal of the differential amplifier noise suppression unit, which effectively protects the control module, thereby improving the stability of system control, making the control more reliable, and effectively preventing electrical fires. Attached Figure Description

[0022] Figure 1 This is a system module structure diagram of the present invention.

[0023] Figure 2 This is a schematic diagram of the current acquisition circuit of the present invention.

[0024] Figure 3 This is a schematic diagram of the signal processing circuit of the present invention.

[0025] Figure 4 This is a schematic diagram of the control circuit for the control module and the switch protection module of the present invention. Detailed Implementation

[0026] The foregoing and other technical contents, features and effects of the present invention are described in conjunction with the appendix below. Figure 1 To be continued Figure 4 The detailed description of the embodiments will make this clear. All structural details mentioned in the following embodiments are based on the accompanying drawings.

[0027] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings.

[0028] like Figure 1 As shown, a smart control cabinet for active protection of safe electricity use includes an overcurrent detection module, a control module, and a switch protection module. The overcurrent detection module includes a current acquisition circuit and a signal processing circuit. The current acquisition circuit is used to detect the magnitude of the current in the main power supply circuit and send the detection signal to the signal processing circuit for processing.

[0029] Specifically, such as Figure 2 As shown, the current acquisition circuit includes a current transformer CT1 and an operational amplifier AR1. One end of the current transformer CT1 is connected to one end of a resistor R1, and then to the non-inverting input of the operational amplifier AR1 through a resistor R2. The other end of the current transformer CT1 is connected to the other end of a resistor R2, and then to the inverting input of the operational amplifier AR1 through a resistor R3. The output of the operational amplifier AR1 is connected to one end of an adjustable resistor RL1 and a capacitor C1, and to the input of the signal processing circuit. The other end of the capacitor C1 is connected to the other end of the adjustable resistor RL1 and the inverting input of the operational amplifier AR1 through a resistor R4. The current transformer CT1 samples the current in the main power supply circuit and sends the sampled signal to the operational amplifier AR1 for differential amplification. During the amplification process, the resistor R4 and the capacitor C1 provide phase compensation for the sampled signal amplification, improving the stability of the signal output. At the same time, adjusting the resistance value of the adjustable resistor RL1 can change the amplification factor of the operational amplifier AR1 to facilitate matching the system parameter requirements.

[0030] Because the current acquisition signal is easily mixed with external interference noise, and the signal attenuation in the transmission line affects its stability, a signal processing circuit is used to further process the output signal of the current acquisition circuit. The signal processing circuit includes a differential amplifier noise suppression unit, a feedback adjustment unit, and a signal output stabilization unit. The differential amplifier noise suppression unit includes a differential amplifier for amplifying and enhancing the detection signal, and a combined adjustment tube for following and adjusting the output signal of the differential amplifier. A band-stop filter for eliminating harmful noise in the main power supply circuit is also provided between the differential amplifier and the combined adjustment tube. The feedback adjustment unit is used to provide feedback on the output signal of the differential amplifier noise suppression unit and suppress the fluctuations generated when the band-stop filter is working. The signal output stabilization unit is used to stabilize the amplitude of the detection signal processed by the feedback adjustment unit and then send it to the control module. The control module changes the on / off state of the main power supply circuit by controlling the switch protection module.

[0031] Specifically, such as Figure 3 As shown, the differential amplifier includes operational amplifier AR2 and operational amplifier AR3. The output terminal of operational amplifier AR2 is connected to the input terminal of the combined regulating transistor. The non-inverting input terminal of operational amplifier AR2 is connected to the non-inverting input terminal of operational amplifier AR3. The inverting input terminal and output terminal of operational amplifier AR3 are connected to the input terminal of the band-stop filter. The output terminal of the band-stop filter is connected to the control terminal of the combined regulating transistor.

[0032] The combined regulating transistors include transistors VT1 and VT2. The collector of transistor VT1 is connected to one end of resistors R7 and R8. The other end of resistor R7 is connected to the output terminal of operational amplifier AR2. The other end of resistor R8 is connected to the emitter of transistor VT2 and grounded through capacitor C4. The collector of transistor VT2 is connected to the base of transistor VT1. The emitter of transistor VT1 is connected to the inverting input terminal of operational amplifier AR2 through parallel resistor R6 and capacitor C3. The base of transistor VT2 is connected to the output terminal of the band-stop filter through resistor R11.

[0033] The band-stop filter includes resistors R9 and R10, inductors L2 and L3, and capacitors C5 and C6. One end of resistor R9 is connected to the output terminal of operational amplifier AR3. The other end of resistor R9 is connected to one end of inductor L3 and the control terminal of the combined regulating transistor through parallel inductor L2 and capacitor C5. The other end of inductor L3 is grounded through parallel capacitor C6 and resistor R10.

[0034] The specific workflow and principle of the differential amplifier noise suppression unit are as follows: First, operational amplifiers AR2 and AR3 in the differential amplifier divide the output signal of the current acquisition circuit into two differential signals, and input the two differential signals to the combined regulating transistor for amplification and conditioning. The common-mode interference in the current acquisition signal is suppressed by using the differential amplifier principle, eliminating the uncertainty of the amplification component parameters and the interference of external environmental factors such as temperature and power supply. At the same time, a combined transistor is used as a follower amplification component to quickly increase the amplitude of the attenuated signal, thereby improving the system response speed. Then, in order to prevent the power supply network frequency fluctuations from interfering with the current acquisition signal, a band-stop filter is set between operational amplifier AR3 and the combined regulating transistor. The band-stop filter uses a two-order parallel RLC filter network to suppress and attenuate the fluctuation frequency in the power supply network, thereby effectively eliminating the interference of harmful signals on the current acquisition process and improving the measurement accuracy.

[0035] Furthermore, an LC filter is provided between the differential amplifier and the operational amplifier AR1. The LC filter includes an inductor L1, one end of which is connected to the output terminal of the operational amplifier AR1, and the other end of which is grounded through a parallel resistor R5 and a capacitor C2, and connected to the inverting input terminal of the operational amplifier AR2 through a diode VD1. By placing an LC filter before the input terminal of the differential amplifier, high-frequency interference signals can be initially filtered out, thereby improving the interference suppression capability of the differential amplifier noise suppression unit.

[0036] Furthermore, the input terminal of the differential amplifier is also equipped with a bias circuit, which includes a potentiometer RP1. One end of the potentiometer RP1 is connected to a -5V power supply through a resistor R18 and grounded through a resistor R19. The other end of the potentiometer RP1 is connected to a +5V power supply through a resistor R21 and grounded through a resistor R20. The adjustment terminal of the potentiometer RP1 is connected to the inverting input terminal of the operational amplifier AR2. By adjusting the potentiometer RP1, the input terminal of the differential amplifier is zeroed, thereby improving the overall performance of the amplifier, eliminating errors, improving the linearity of the current acquisition signal amplification output, and making the measurement more accurate.

[0037] The differential amplifier noise suppression unit uses a band-stop filter, which effectively suppresses fluctuation noise from the power supply network, resulting in a cleaner current detection signal output. However, when the RLC filter network is working, the inductor and capacitor form conjugate poles, which disrupts the stability of the signal amplification loop. Therefore, a feedback adjustment unit is set up to provide feedback on the output signal of the differential amplifier noise suppression unit. Specifically, the feedback adjustment unit includes MOSFETs Q1 and Q2. The source of MOSFET Q1 is connected to the base of transistor VT2, and the gate of MOSFET Q1 is connected to the emitter of transistor VT1 through resistor R12. The drain of MOSFET Q1 is connected to the cathode of Zener diode DZ1, and the anode of Zener diode DZ1 is connected to the gate of MOSFET Q2 and grounded through parallel resistor R13 and capacitor C7. The source of MOSFET Q2 is connected to the output terminal of the band-stop filter through diode VD2, and the drain of MOSFET Q2 is grounded.

[0038] During the operation of the feedback adjustment unit, MOSFET Q1 is used to sample and amplify the output signal of the differential amplifier noise suppression unit. After the amplitude of the sampled signal is stabilized by Zener diode DZ1, MOSFET Q2 is driven to conduct. Resistor R13 and capacitor C7 compensate and adjust the gate conduction signal of MOSFET Q2. The RC compensation adjustment is used to eliminate system fluctuations. Then, MOSFET Q2 is used as the adjustment transistor to feed back its source amplified signal to the output of the band-stop filter, thereby performing negative feedback adjustment on the band-stop filtered signal, effectively suppressing the amplitude fluctuation of the detection signal, making the control terminal conduction signal of the combined adjustment transistor more stable, and ensuring the stability of the overall loop operation of the differential amplifier noise suppression unit.

[0039] To make the measurement results more accurate, the output signal of the differential amplification and noise suppression unit is sent to the signal output stabilization unit for further processing. The signal output stabilization unit includes transistors VT3 and VT4. The collector of transistor VT3 is connected to one end of capacitor C8 and the cathode of Zener diode DZ2, and is connected to the output terminal of the differential amplification and noise suppression unit through resistor R14. The other end of capacitor C8 is connected to the base of transistor VT3 and the collector of transistor VT4 through the anode of Zener diode DZ1. The emitter of transistor VT3 is connected to resistor R15, one end of potentiometer RP2, and the control module. The emitter of transistor VT4 is connected to resistor R16, one end of capacitor C9, and the other end of resistor R15. The other end of resistor R16 is connected to the drain of MOSFET Q1. The other end of capacitor C9 is grounded. The base-drain potentiometer of transistor VT4 is the adjustment terminal of potentiometer RP2. The other end of potentiometer RP2 is grounded through resistor R17.

[0040] In this circuit, Zener diode DZ2 and capacitor C8 are used to stabilize the output signal of the differential amplifier noise suppression unit before driving transistor VT3 to conduct. During the signal output stabilization process, transistor VT3 acts as the adjustment transistor to stabilize the signal output, while transistor VT4 acts as the feedback adjustment transistor. The output signal of transistor VT3 is sampled by potentiometer RP2, and the sampled signal is amplified and fed back to the adjustment transistor. To reduce the impact of high-amplitude current on the control module, when a short-circuit current occurs in the power supply circuit, the output signal voltage amplitude of transistor VT3 will increase rapidly, and the sampled signal current will also increase accordingly. That is, the base current of transistor VT4 increases. The feedback adjustment suppresses the base voltage amplitude of transistor VT3, thereby effectively preventing transistor VT3 from emitting extremely high-amplitude signals, effectively protecting the control module, and thus improving the stability of system control.

[0041] Specifically, such as Figure 4 As shown, the control module includes a microcontroller and a peripheral switch drive circuit. The switch protection module is a power distribution circuit breaker K1. The microcontroller controls the operation of the power distribution circuit breaker K1 by driving the peripheral switch drive circuit. The peripheral switch drive circuit includes a transistor VT5. The base of the transistor VT5 is connected to the control output terminal of the microcontroller through a resistor R22 and grounded through a capacitor C10. The collector of the transistor VT5 is connected to the VCC power supply through the drive coil of the power distribution circuit breaker K1. The normally open contact of the power distribution circuit breaker K1 is set on the main power supply circuit. This embodiment uses an STM32 microcontroller as an example. The built-in analog-to-digital converter (ADC) converts the output signal of the overcurrent detection module into a digital signal, and mature data processing technology is used to process and judge the measured signal. The specific workflow is as follows: When the main power supply circuit is working normally, the amplitude of the output signal of the overcurrent detection module is within a safe range. At this time, the microcontroller's control output terminal outputs a high-level signal, transistor VT5 conducts, the drive coil of the power distribution circuit breaker is energized and its normally open contact closes, and the main power supply circuit is connected. When a short circuit occurs in the main power supply circuit, the amplitude of the output signal of the overcurrent detection module exceeds the preset safety threshold parameter of the microcontroller. At this time, the microcontroller's control output terminal outputs a low-level signal, transistor VT5 is cut off, the drive coil of the power distribution circuit breaker is de-energized, and its normally open contact opens, thereby cutting off the main power supply circuit and thus actively protecting against short-circuit faults.

[0042] In summary, the intelligent control cabinet of this invention forms an active power protection system by incorporating an overcurrent detection module, a control module, and a switch protection module within the cabinet. The overcurrent detection module consists of a current acquisition circuit and a signal processing circuit. The current acquisition circuit collects the current magnitude in the main power supply circuit and sends the acquired signal to the signal processing circuit for conditioning. Differential amplification is used to eliminate interference from external environmental factors, while a combined transistor is used as a follower amplification component to quickly amplify the attenuated signal amplitude. A band-stop filter network is used to suppress and attenuate fluctuations in the power supply network, thereby improving measurement accuracy. A feedback adjustment unit performs negative feedback adjustment on the band-stop filtered signal to effectively suppress fluctuations in the detection signal amplitude. Finally, a signal output stabilization unit stabilizes the output signal of the differential amplification and noise suppression unit, effectively protecting the control module and improving the stability of the system control. This makes the entire system more accurate in monitoring short-circuit faults and more reliable in control, effectively preventing electrical fires.

[0043] The above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and it should not be considered that the specific implementation of the present invention is limited to this. For those skilled in the art to which the present invention pertains and related fields, any extensions, operation methods, and data substitutions made based on the technical solution concept of the present invention should fall within the protection scope of the present invention.

Claims

1. A smart control cabinet for active protection of safe electricity use, comprising an overcurrent detection module, a control module, and a switch protection module, characterized in that: The overcurrent detection module includes a current acquisition circuit and a signal processing circuit. The current acquisition circuit is used to detect the magnitude of the current in the main power supply circuit and send the detection signal to the signal processing circuit for processing. The signal processing circuit includes a differential amplifier noise suppression unit, a feedback adjustment unit, and a signal output stabilization unit. The differential amplifier noise suppression unit includes a differential amplifier for amplifying and enhancing the detection signal, and a combined adjustment transistor for following and adjusting the output signal of the differential amplifier. A band-stop filter for eliminating harmful noise in the main power supply circuit is also provided between the differential amplifier and the combined adjustment transistor. The feedback adjustment unit is used to provide feedback on the output signal of the differential amplifier noise suppression unit and suppress fluctuations generated when the band-stop filter is working. The signal output stabilization unit is used to stabilize the detection signal processed by the feedback adjustment unit before sending it to the control module. The control module changes the on / off state of the main power supply circuit by controlling the switch protection module; The differential amplifier includes operational amplifier AR2 and operational amplifier AR3. The output terminal of operational amplifier AR2 is connected to the input terminal of the combined regulating transistor. The non-inverting input terminal of operational amplifier AR2 is connected to the non-inverting input terminal of operational amplifier AR3. The inverting input terminal and output terminal of operational amplifier AR3 are connected to the input terminal of the band-stop filter. The output terminal of the band-stop filter is connected to the control terminal of the combined regulating transistor. The combined regulating transistors include transistors VT1 and VT2. The collector of transistor VT1 is connected to one end of resistors R7 and R8. The other end of resistor R7 is connected to the output terminal of operational amplifier AR2. The other end of resistor R8 is connected to the emitter of transistor VT2 and grounded through capacitor C4. The collector of transistor VT2 is connected to the base of transistor VT1. The emitter of transistor VT1 is connected to the inverting input terminal of operational amplifier AR2 through parallel resistor R6 and capacitor C3. The base of transistor VT2 is connected to the output terminal of the band-stop filter through resistor R11. The band-stop filter includes resistors R9 and R10, inductors L2 and L3, and capacitors C5 and C6. One end of resistor R9 is connected to the output terminal of operational amplifier AR3. The other end of resistor R9 is connected to one end of inductor L3 and the control terminal of the combined regulating tube through parallel inductor L2 and capacitor C5. The other end of inductor L3 is grounded through parallel capacitor C6 and resistor R10. The feedback adjustment unit includes MOSFET Q1 and MOSFET Q2. The source of MOSFET Q1 is connected to the base of transistor VT2. The gate of MOSFET Q1 is connected to the emitter of transistor VT1 through resistor R12. The drain of MOSFET Q1 is connected to the cathode of Zener diode DZ1. The anode of Zener diode DZ1 is connected to the gate of MOSFET Q2 and grounded through parallel resistor R13 and capacitor C7. The source of MOSFET Q2 is connected to the output terminal of the band-stop filter through diode VD2. The drain of MOSFET Q2 is grounded. The signal output stabilization unit includes transistors VT3 and VT4. The collector of transistor VT3 is connected to one end of capacitor C8 and the cathode of Zener diode DZ2, and is connected to the output terminal of the differential amplifier noise suppression unit through resistor R14. The other end of capacitor C8 is connected to the base of transistor VT3 and the collector of transistor VT4 through the anode of Zener diode DZ1. The emitter of transistor VT3 is connected to resistor R15, one end of potentiometer RP2, and the control module. The emitter of transistor VT4 is connected to resistor R16, one end of capacitor C9, and the other end of resistor R15. The other end of resistor R16 is connected to the drain of MOSFET Q1. The other end of capacitor C9 is grounded. The base of transistor VT4 is connected to the adjustment terminal of potentiometer RP2. The other end of potentiometer RP2 is grounded through resistor R17.

2. The intelligent control cabinet for active protection of safe electricity use according to claim 1, characterized in that: The current acquisition circuit includes a current transformer CT1 and an operational amplifier AR1. One end of the current transformer CT1 is connected to one end of a resistor R1 and is connected to the non-inverting input of the operational amplifier AR1 through a resistor R2. The other end of the current transformer CT1 is connected to the other end of a resistor R2 and is connected to the inverting input of the operational amplifier AR1 through a resistor R3. The output of the operational amplifier AR1 is connected to an adjustable resistor RL1, one end of a capacitor C1, and the input of the signal processing circuit. The other end of the capacitor C1 is connected to the other end of the adjustable resistor RL1 and the inverting input of the operational amplifier AR1 through a resistor R4.

3. The intelligent control cabinet for active protection of safe electricity use according to claim 2, characterized in that: An LC filter is also provided between the differential amplifier and the operational amplifier AR1. The LC filter includes an inductor L1. One end of the inductor L1 is connected to the output terminal of the operational amplifier AR1, and the other end of the inductor L1 is grounded through a parallel resistor R5 and a capacitor C2, and is connected to the inverting input terminal of the operational amplifier AR2 through a diode VD1.

4. The intelligent control cabinet for active protection of safe electricity use according to claim 3, characterized in that: The input terminal of the differential amplifier is also provided with a bias circuit, which includes a potentiometer RP1. One end of the potentiometer RP1 is connected to a -5V power supply through a resistor R18 and grounded through a resistor R19. The other end of the potentiometer RP1 is connected to a +5V power supply through a resistor R21 and grounded through a resistor R20. The adjustment terminal of the potentiometer RP1 is connected to the inverting input terminal of the operational amplifier AR2.

5. The intelligent control cabinet for active protection of safe electricity use according to claim 1, characterized in that: The control module includes a microcontroller and an external switch drive circuit. The switch protection module is a power distribution circuit breaker. The microcontroller controls the operation of the power distribution circuit breaker by driving the external switch drive circuit.

Images