Auxiliary testing device for circuit breaker

Abstract

The auxiliary testing device comprises a lithium battery and electric quantity management unit, a voltage attenuation unit, a signal conditioning unit, a signal isolation unit, an analog-to-digital conversion unit, an ARM main control unit, a wireless transmit-receive unit, a latch-up protection unit, a sound-light alarm unit and an LED display unit. The voltage attenuation unit is sequentially connected with the signal conditioning unit, the signal isolation unit and the analog-to-digital conversion unit, and the analog-to-digital conversion unit, the lithium battery and electric quantity management unit, the wireless transceiving unit, the latch-up protection unit, the sound-light alarm unit and the LED display unit are respectively connected with the ARM main control unit. The circuit breaker operating characteristic tester control signal locking device can effectively lock a circuit breaker operating characteristic tester control signal, gives an alarm to field testers, avoids the influence on a switching coil and a secondary control system possibly caused by switching on and switching off a circuit breaker by an operating power supply live-line use instrument, greatly improves the safety of field work, and improves the working efficiency. And the intrinsic safety of power grid equipment is effectively ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to power test technical field, concretely relates to a circuit breaker auxiliary testing device. BACKGROUND

[0002] The high voltage circuit breaker is a kind of electrical equipment in high voltage power transmission, and it is the device for switching on and off power transmission loop, and is the indispensable equipment in power plant and distribution device of transformer substation.The high voltage circuit breaker shoulders the control and protection double tasks in power system, and its state directly influences the safe operation of power system, so the condition detection of high voltage circuit breaker mechanical characteristics is very important.

[0003] When the circuit breaker operating characteristic test is carried out on site, the operating power is frequently turned on and off, and after energy storage and pressure, the operating power is not disconnected to carry out the test of opening and closing, which can affect the insulation of opening and closing coil, the problem of substation DC control system.

[0004] Therefore, it is urgent to develop a circuit breaker operating characteristic auxiliary testing device based on voltage isolation measurement technology, to lock the circuit breaker operating characteristic tester control signal, and alarm the on-site test personnel, to avoid the influence on opening and closing coil and secondary control system caused by operating power live instrument opening and closing circuit breaker, and effectively guarantee the intrinsic safety of power grid equipment. UTILITY MODEL CONTENTS

[0005] In view of the above problems, the utility model provides a circuit breaker auxiliary testing device.

[0006] To achieve the above object, the utility model adopts the following technical scheme:

[0007] A circuit breaker auxiliary testing device, comprising lithium battery and electric quantity management unit, voltage attenuation unit, signal conditioning unit, signal isolation unit, analog-digital conversion unit, ARM master control unit, wireless transceiver unit, locking protection unit, audible and visual alarm unit, LED display unit;

[0008] The voltage attenuation unit is connected with signal conditioning unit, signal isolation unit and analog-digital conversion unit in sequence, and the analog-digital conversion unit, lithium battery and electric quantity management unit, wireless transceiver unit, locking protection unit, audible and visual alarm unit and LED display unit are connected with ARM master control unit respectively.

[0009] As the preferred of the above scheme, the lithium battery and electric quantity management unit include lithium battery, lithium battery electric quantity management chip and charging chip connected with the lithium battery.

[0010] As the preferred of the above scheme, the voltage attenuation unit converts the high voltage of circuit breaker to ground into low voltage by resistance voltage division mode.

[0011] As a preferred embodiment of the above scheme, the signal conditioning unit uses an instrumentation operational amplifier and a low-pass filter to condition the signal transmitted from the voltage attenuation unit.

[0012] As a preferred embodiment of the above scheme, the signal isolation unit adopts the high-voltage ground of the isolation operational amplifier and the ground of the analog-to-digital acquisition and conversion unit.

[0013] As a preferred embodiment of the above scheme, the analog-to-digital conversion unit uses an AD acquisition chip for analog-to-digital conversion.

[0014] As a preferred embodiment of the above scheme, the wireless transceiver unit uses Bluetooth, Wi-Fi, or LoRa to wirelessly transmit the collected voltage signals and prompt information to the circuit breaker test host.

[0015] As a preferred embodiment of the above scheme, the interlocking protection unit uses a Hall sensor to isolate and collect current signals, and monitors the output current of the circuit breaker host in real time.

[0016] Due to the above structure, the beneficial effects of this utility model are as follows:

[0017] 1. The system uses wireless transmission to achieve control output and data acquisition and analysis, effectively protecting the safety of personnel and equipment.

[0018] 2. Powered by a high-capacity lithium battery, making it easy to carry and work outdoors.

[0019] 3. By developing DC voltage isolation measurement technology, intelligent handling strategies, and human-machine interactive alarm modules, stable, efficient, and reliable isolation sampling of circuit breaker control voltage can be achieved.

[0020] 4. By adopting an intelligent handling strategy, the control signal of the circuit breaker action characteristic tester is effectively blocked, and an alarm is triggered for on-site test personnel. This avoids the potential impact on the opening and closing coils and secondary control system that may occur when the instrument is used to open and close the circuit breaker while the operating power supply is energized. This greatly improves the safety of on-site work and effectively ensures the inherent safety of power grid equipment. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0022] Figure 1 This is a schematic diagram of the structure of this utility model;

[0023] Figure 2 This is a circuit diagram of the voltage attenuation unit of this utility model;

[0024] Figure 3 This is a circuit diagram of the signal conditioning unit of this utility model;

[0025] Figure 4 This is a circuit diagram of the signal isolation unit of this utility model;

[0026] Figure 5 The circuit diagram for conditioning the current signal isolated and collected by the Hall sensor in the interlocking protection unit of this utility model;

[0027] Figure 6 This is a circuit diagram of the interlocking protection unit of this utility model, which cuts off and opens high-power current. Detailed Implementation

[0028] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0029] like Figure 1 As shown, this embodiment provides an auxiliary testing device for a circuit breaker, including a lithium battery and power management unit 1, a voltage attenuation unit 2, a signal conditioning unit 3, a signal isolation unit 4, an analog-to-digital conversion unit 5, an ARM main control unit 6, a wireless transceiver unit 7, a lockout protection unit 8, an audible and visual alarm unit 9, and an LED display unit 10. The voltage attenuation unit 2 is connected in sequence to the signal conditioning unit 3, the signal isolation unit 4, and the analog-to-digital conversion unit 5 via wires. The analog-to-digital conversion unit 5, the lithium battery and power management unit 1, the wireless transceiver unit 7, the lockout protection unit 8, the audible and visual alarm unit 9, and the LED display unit 10 are respectively connected to the ARM main control unit 6 via wired or wireless means.

[0030] In this embodiment, the lithium battery and power management unit 1 includes a lithium battery and a lithium battery power management chip and a charging chip connected to the lithium battery. The battery is used to provide power to the testing device, and the chip is used to monitor the power and power consumption of the lithium battery in real time to ensure the normal and reliable operation of the lithium battery and provide a reliable power supply to the system.

[0031] In this embodiment, the voltage attenuation unit 2 uses a resistor voltage divider to convert the high voltage to ground of the circuit breaker into a low voltage, facilitating subsequent signal conditioning. To ensure the accuracy of the voltage divider signal, an Omron signal relay is used to switch the low-voltage arm, dividing it into multiple range levels. The specific circuit diagram is shown below. Figure 2As shown, the high-voltage arm consists of resistors R15, R5, and R2, and the low-voltage arm consists of resistors R1 and R6. Relay K13 is used to switch the low-voltage arm voltage division ratio. Initially, relay K13 is normally closed. In the first position, the low-voltage arm consists of resistors R1 and R6 in parallel with a resistance of 2KΩ, while the high-voltage arm consists of resistors R15, R2, and R5 with a resistance of 200KΩ. The first voltage division ratio is 100:1, suitable for voltage attenuation in the high-voltage range. When relay K13 receives a control signal and switches to normally open, it switches to the second position. The low-voltage arm resistance is now 6.8KΩ (equivalent to the resistance of R1). In this second position, the voltage division ratio is 30:1, suitable for voltage attenuation in the low-voltage range.

[0032] In this embodiment, the signal conditioning unit 3 uses an instrumentation operational amplifier and a low-pass filter to condition the signal transmitted from the voltage attenuation unit 2. The specific circuit diagram is shown below. Figure 3 As shown, the input terminal of signal conditioning unit 3 is connected between the high-voltage arm and the low-voltage arm of voltage attenuation unit 2. Signal conditioning unit 3 consists of diode D9, resistors R10 and R18, capacitors C9, C48, C43, and C55, and instrumentation operational amplifier U16. D9 is a bidirectional fast overvoltage protection for the input signal. R10 and C9 form a low-pass filter circuit to filter the input signal. R18 and C55 form a low-pass filter circuit to filter the signal after conversion by operational amplifier U16. Instrumentation operational amplifier U16 can increase the input impedance of the signal and convert the signal from differential to single-ended signal for convenient signal isolation in subsequent stages.

[0033] In this embodiment, the signal isolation unit 4 uses the high-voltage ground of the isolation circuit breaker and the ground of the analog-to-digital converter to ensure the safety of operators and the device. The specific circuit diagram is shown below. Figure 4 As shown, the input terminal of signal isolation unit 4 is connected to operational amplifier U16 of signal conditioning unit 3. Signal isolation unit 4 consists of operational amplifier U17, resistor R27, capacitor C47, and diodes D4 and D6. The isolation operational amplifier U17 uses an ISO124 wide-range, high-bandwidth isolation operational amplifier to isolate the high-voltage side signal. R27 and C47 form a low-pass filter to filter the signal, and D4 and D5 form a clamping circuit to clamp the signal between 0.7-3.3V to protect the subsequent AD analog-to-digital converter chip.

[0034] In this embodiment, the analog-to-digital conversion unit 5 uses a 16-bit high-precision AD acquisition chip AD7606 for analog-to-digital conversion to detect the voltage of the high-voltage circuit breaker to ground in real time.

[0035] In this embodiment, the ARM main control unit 6 employs a 32-bit microprocessor for real-time signal interaction with the power management unit, performing analog-to-digital conversion on the data from the analog-to-digital conversion unit 5, and implementing intelligent processing strategies based on the collected voltage signals. It controls the interlocking protection unit 8 and the audible and visual alarm unit 9 to effectively interlock the control signals of the circuit breaker operating characteristic tester and issue alarms to on-site testing personnel. The signals are wirelessly transmitted to the circuit breaker testing host device in real-time via the wireless transceiver unit 7.

[0036] In this embodiment, the wireless transceiver unit 7 uses Bluetooth, Wi-Fi, or LoRa to wirelessly transmit the collected voltage signal and prompt information to the circuit breaker test host.

[0037] In this embodiment, the interlocking protection unit 8 uses a Hall sensor to isolate and collect current signals, and monitors the output current of the circuit breaker host in real time, which is used to cut off the voltage and power output of the circuit breaker test host to protect the host. The specific circuit diagram is as follows: Figure 5 and Figure 6 As shown, Figure 5 It is used to condition the current signal isolated and acquired by the Hall sensor. It consists of resistors R20, R23, R25, R29, capacitor C15, diodes D12 and D13, and operational amplifier U2-A. Resistors R20, R23, R25 and operational amplifier U2-A form a non-inverting proportional amplifier circuit to amplify the isolated current signal of the Hall sensor. R29 and C15 form a low-pass filter circuit. D12 and D13 form a clamping circuit to clamp the signal. Figure 6 This device is used for interlocking protection to cut off and open high-power currents. It consists of capacitor C1, relay K6, diode D2, and Darlington transistor chip U1. Darlington transistor chip U1 is a ULN2003AD used to increase the drive current to drive the relay. D2 is a 1N4148 diode used to prevent sudden changes in voltage and current in the circuit and to provide a power dissipation path for the reverse electromotive force of relay K6. Relay K6 is an Omron high-current power relay used for interlocking protection of the current line. Capacitor C1 is used to reduce the arc energy on the contacts of relay K6 and to make the contacts easier to close and open, thereby reducing the wear of the contacts and extending the service life of the AC relay.

[0038] In this embodiment, the audible and visual alarm unit 9 can be an audible and visual alarm device, used to alert the operator that there is a high voltage leakage in the circuit breaker and to pay attention to personal safety.

[0039] In this embodiment, the LED display unit 10 can be an LED display screen, which is used to display the voltage information on the high-voltage side in real time for easy viewing and observation by operators.

[0040] The working principle of the above structure:

[0041] First, under the premise of ensuring safety, the operator connects the control power supply of the circuit breaker switch tester to the intelligent auxiliary device, and the intelligent auxiliary device is connected to the closing point, opening point and common terminal of the secondary terminal block of the circuit breaker.

[0042] After the auxiliary device is powered on, the lithium battery power management unit 1 and the ARM main control unit 6 interact in real time to display the power status. The high-voltage signal on the secondary side of the circuit breaker is attenuated to a low-voltage signal by the voltage attenuation unit 2 and then sent to the signal conditioning unit 3. The signal conditioning unit 3 filters and conditions the signal before sending it to the signal isolation unit 4. The signal isolation unit 4 isolates the high-voltage and low-voltage signals, and the isolated signal is then sent to the analog-to-digital converter unit 5. The analog-to-digital converter unit 5 converts the analog signal into a digital signal, which is then displayed in real time on the LED display unit 10 by the ARM main control unit 6. The wireless transceiver unit 7 receives control signals from the circuit breaker test host via wireless signals to achieve control.

[0043] When the ARM main control unit 6 detects that the voltage on the high-voltage secondary side exceeds the safe voltage, it controls the interlocking protection unit 8 through an intelligent handling strategy to cut off the voltage and power output of the circuit breaker test host. The current information is then transmitted back to the circuit breaker test host via the wireless transceiver unit 7. The ARM main control unit 6 controls the audible and visual alarm unit 9 to execute an audible and visual alarm, alerting the operator that the voltage at the site is too high.

[0044] This embodiment achieves stable, efficient, and reliable isolated sampling of circuit breaker control voltage by developing DC voltage isolation measurement technology, intelligent handling strategies, and a human-machine interactive alarm module. Furthermore, the intelligent handling strategy effectively blocks the control signal of the circuit breaker operating characteristic tester and alarms the on-site testing personnel. This avoids the potential impact on the opening and closing coils and secondary control system caused by operating the instrument with the power supply energized, greatly improving the safety of on-site work and effectively ensuring the inherent safety of power grid equipment.

[0045] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A circuit breaker auxiliary testing device characterized by: The circuit comprises a lithium battery and an electric quantity management unit, a voltage attenuation unit, a signal conditioning unit, a signal isolation unit, an analog-digital conversion unit, an ARM main control unit, a wireless transceiving unit, a lockout protection unit, an audible and light alarm unit, and an LED display unit. The voltage attenuation unit is connected with the signal conditioning unit, the signal isolation unit, and the analog-digital conversion unit in sequence, and the analog-digital conversion unit, the lithium battery and the electric quantity management unit, the wireless transceiving unit, the lockout protection unit, the audible and light alarm unit, and the LED display unit are connected with the ARM main control unit.

2. The circuit breaker auxiliary testing device of claim 1, wherein: The lithium battery and the electric quantity management unit comprise a lithium battery, a lithium battery electric quantity management chip connected with the lithium battery, and a charging chip.

3. The circuit breaker auxiliary testing device of claim 1, wherein: The voltage attenuation unit converts the high voltage of the circuit breaker to the ground into low voltage by using a resistance voltage division method.

4. The circuit breaker auxiliary testing device of claim 1, wherein: The signal conditioning unit uses an instrument operational amplifier and a low-pass filter to condition the signal transmitted by the voltage attenuation unit.

5. The circuit breaker auxiliary testing device of claim 1, wherein: The signal isolation unit uses an isolation operational amplifier to isolate the high voltage ground of the circuit breaker and the ground of the analog-digital conversion unit.

6. The circuit breaker auxiliary testing device of claim 1, wherein: The analog-digital conversion unit uses an AD acquisition chip to perform analog-digital conversion.

7. The circuit breaker auxiliary testing device of claim 1, wherein: The wireless transceiving unit uses Bluetooth or WIF or LORA to wirelessly transmit the collected voltage signal and prompt information to a circuit breaker test host.

8. The circuit breaker auxiliary testing device of claim 1, wherein: The lockout protection unit uses a Hall sensor to isolate and collect the current signal and to monitor the output current of the circuit breaker host in real time.

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