CN211085641U - Mechanical characteristic on-line monitoring device for high-voltage isolating switch operating mechanism - Google Patents
Mechanical characteristic on-line monitoring device for high-voltage isolating switch operating mechanism Download PDFInfo
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- CN211085641U CN211085641U CN201921626690.6U CN201921626690U CN211085641U CN 211085641 U CN211085641 U CN 211085641U CN 201921626690 U CN201921626690 U CN 201921626690U CN 211085641 U CN211085641 U CN 211085641U
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Abstract
The utility model relates to a monitoring field especially relates to high voltage isolator operating device mechanical characteristic on-line monitoring device, include: the current acquisition circuit is used for acquiring current signals; the angular displacement sensor is fixed on the output shaft of the motor, rotates along with the main shaft of the motor and is used for measuring the rotation angle of the motor; and the microprocessor unit is connected with the current transformer and the angular displacement sensor and is used for realizing online monitoring on the mechanical characteristics of the high-voltage isolating switch operating mechanism according to the current of the motor during working and the rotation angle of the motor. The utility model discloses possess following beneficial effect: collecting current signals through a current collecting circuit; measuring the rotation angle of the motor through an angular displacement sensor; the mechanical characteristics of the high-voltage isolating switch operating mechanism are monitored on line through the microprocessor unit; the failure judgment is carried out by utilizing a verification mode combining the two methods, so that the monitoring safety is improved, and the misjudgment is prevented.
Description
Technical Field
The utility model relates to a monitoring field especially relates to high voltage isolator operating device mechanical characteristic on-line monitoring device.
Background
In a power network, a GIS high-voltage isolating switch is used for isolating live-line running electrical equipment from power-off maintenance or standby equipment during maintenance work, so that the isolating switch is required to have a sufficient on-off isolation distance.
The action state of the isolating switch can be observed by naked eyes through an outdoor open isolating switch, but the isolating switch in the GIS equipment is sealed in an insulating cylinder by using SF6 gas, the opening and closing in-place condition of a moving contact and a static contact cannot be directly observed, and the action state of the disconnecting switch can be indirectly judged only through a position pointer on a mechanism box, an opening and closing lamp in a convergence control cabinet and a background position.
The transmission shaft sleeve is broken, the connecting rod is poor in material, so that the position of a stroke switch is not correct, the faults of improper opening and closing of a mechanism, insufficient opening distance of a moving contact and a static contact, failure in position judgment and the like can be caused, if the faults are found out untimely, serious accident events such as ' pulling a disconnecting link with load ', transmitting power with a ground knife ' and the like can be caused, and the power grid and personal safety are seriously damaged.
At present, most of measures for overcoming the defects are to mark the GIS connecting rod, but the defects are as follows: mechanism connecting rods of part of manufacturers are arranged in the mechanism box and cannot be used for marking; due to the adoption of a scribing mode, the workload is large, and a large amount of switching operation has potential safety hazards; the observation means of the identification line is seriously insufficient, the GIS has compact structure, blind areas exist in observation, and the observation is difficult at night; if the transmission shaft and the moving contact are connected and are released, the marking mark cannot play a role.
SUMMERY OF THE UTILITY MODEL
In order to solve the problem, the utility model provides a high voltage isolator operating device mechanical characteristic on-line monitoring device.
High voltage isolator operating device mechanical properties on-line monitoring device includes:
a current acquisition circuit, the current acquisition circuit comprising: the current transformer U1, diodes D1, D2, D3, D4, capacitors C1, C2 and a sampling resistor R1, wherein the current transformer U1 passes through any power line of a motor working power supply and is used for measuring current when the motor works, the anode of the diode D1 is connected with a common ground, the cathode of the diode D1 is connected with the second end of the current transformer U1 and the anode of the diode D2, the cathode of the diode D2 is connected with the cathode of the diode D4, one end of the capacitor C1, one end of the capacitor C2, one end of the sampling resistor R1 and a voltage collecting end, the anode of the diode D4 is connected with the cathode of the diode D3 and the first end of the current transformer, the anode of the diode D3 is connected with the common ground, the other end of the capacitor C1 is connected with the common ground, the other end of the capacitor C2 is connected with the common ground, and the other end of the sampling resistor R1 is connected with the common ground;
the angular displacement sensor is fixed on the output shaft of the motor, rotates along with the main shaft of the motor and is used for measuring the rotation angle of the motor;
and the microprocessor unit is connected with the current transformer and the angular displacement sensor and is used for realizing online monitoring on the mechanical characteristics of the high-voltage isolating switch operating mechanism according to the current of the motor during working and the rotation angle of the motor.
Preferably, the current collection circuit further includes:
and the signal high-speed acquisition circuit is connected with the voltage acquisition end and is used for acquiring current signals at a high speed.
Preferably, the signal high-speed acquisition circuit adopts a high-speed acquisition chip AD 9226.
Preferably, the method further comprises the following steps: and the storage unit is connected with the microprocessor unit and is used for storing the current of the motor during working, the rotating angle of the motor and the online monitoring result.
Preferably, the memory unit adopts a memory chip MB85RC 64V.
Preferably, the method further comprises the following steps: one end of the communication unit is connected with the microprocessor unit, and the other end of the communication unit is communicated with the background data management center.
Preferably, the communication unit adopts an RS485 communication unit.
Preferably, the method further comprises the following steps: and the address selection unit is connected with the microprocessor unit, adopts a 12-bit dial switch and is used for selecting and setting an address.
Preferably, the method further comprises the following steps: and the display unit is connected with the microprocessor unit and is used for displaying the online monitoring result.
Preferably, the microprocessor unit employs an STM32 microprocessor.
The utility model discloses possess following beneficial effect:
1. collecting current signals through a current collecting circuit; the rotation angle of the motor is measured through the angular displacement sensor, and the mechanical characteristics of the high-voltage isolating switch operating mechanism are monitored on line through the microprocessor unit according to the current of the motor during working and the rotation angle of the motor;
2. the utility model provides an utilize the verification mode that two kinds of methods combined together to carry out the judgement of trouble, improved the security of monitoring, prevent the erroneous judgement.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Fig. 1 is a schematic structural diagram of an online mechanical characteristic monitoring device for an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 2 is a circuit diagram of a current collecting circuit in an online monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a signal high-speed acquisition circuit in an online monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a storage unit in an online mechanical characteristic monitoring device for an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a communication unit in an online mechanical characteristic monitoring device for an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 6 is a schematic circuit diagram of an RS485 communication unit in the high-voltage isolation switch operating mechanism mechanical characteristic on-line monitoring device according to an embodiment of the present invention
Fig. 7 is a circuit diagram of an address selection unit in an online monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention;
fig. 8 is a schematic structural diagram of a display unit in an online monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to an embodiment of the present invention.
Detailed Description
The technical solution of the present invention will be further described below with reference to the accompanying drawings, but the present invention is not limited to these embodiments.
The basic idea of the embodiment is to collect a current signal through a current collecting circuit; the rotation angle of the motor is measured through the angular displacement sensor, and the mechanical characteristics of the high-voltage isolating switch operating mechanism are monitored on line through the microprocessor unit according to the current of the motor during working and the rotation angle of the motor.
Based on the above thought, an embodiment of the utility model provides a high voltage isolator operating device mechanical properties on-line monitoring device is proposed, as shown in fig. 1, include: the current acquisition circuit is used for acquiring current signals; the angular displacement sensor is fixed on the output shaft of the motor, rotates along with the main shaft of the motor and is used for measuring the rotation angle of the motor; and the microprocessor unit is connected with the current transformer and the angular displacement sensor and is used for realizing online monitoring on the mechanical characteristics of the high-voltage isolating switch operating mechanism according to the current of the motor during working and the rotation angle of the motor.
As shown in fig. 2, the current collection circuit includes: the current transformer U1, the diodes D1, D2, D3, D4, the capacitors C1 and C2 and the sampling resistor R1, wherein the current transformer U1 passes through any power line of a motor working power supply and is used for measuring current when the motor works, the anode of the diode D1 is connected to a common ground, the cathode of the diode D1 is connected to the second end of the current transformer U1 and the anode of the diode D2, the cathode of the diode D2 is connected to the cathode of the diode D4, the anode of the capacitor C1, the one end of the capacitor C2, the one end of the sampling resistor R1 and the voltage acquisition end V1P, the anode of the diode D4 is connected to the cathode of the diode D3 and the first end of the current transformer, the anode of the diode D3 is connected to the common ground, the other end of the capacitor C1 is connected to the common ground, the other end of the capacitor C2 is connected to the common ground, and the other end of the sampling resistor R1 is connected to the.
The diodes D1, D2, D3 and D4 are connected to form a rectifying circuit, and the rectifying circuit is used for converting alternating current signals output by the current transformer into direct current signals. In order to reduce measurement errors and improve measurement accuracy, the rectifying circuit adopts Schottky diodes with small tube voltage drop, and the parameters of the selected Schottky diodes are basically consistent. The capacitors C1 and C2 form a filter circuit, which is used for filtering the dc signal, and reducing the interference of the signal to avoid the misjudgment of the monitoring result. By collecting the voltage at the two ends of the sampling resistor R1, the current flowing through the sampling resistor R1 can be calculated according to the resistance of the sampling resistor R1, and the current of the motor during working can be calculated according to the current transformer.
As a preferable aspect of this embodiment, as shown in fig. 3, the current collection circuit further includes: and the signal high-speed acquisition circuit is connected with the voltage acquisition end and is used for acquiring current signals at a high speed, and the signal high-speed acquisition circuit adopts a high-speed acquisition chip AD 9226.
AD analog-to-digital conversion is all needed to be used to high voltage isolator operating device driving motor electric current, angle displacement sensor voltage signal, and consequently analog-to-digital conversion's precision, slew rate are crucial, STM32 microprocessor is from the analog-to-digital converter who has 16 way 12 bit precisions, but slew rate is slow, and the slew rate is low, consequently, the utility model discloses a high-speed chip AD9226 of gathering gathers monitoring signal. The AD9226 analog-to-digital conversion chip adopts a parallel port communication mode, has high sampling speed, stable working performance and strong anti-interference capability, and can be applied to the field of high-voltage electric fields with serious interference.
The AD9226 is powered by a +3.3V power supply, all conversion inside the chip is carried out by adopting a 65Msps single clock signal, the duty ratio of a sampling clock is about 55%, the chip is in a sampling state during the low level period of the clock signal, and otherwise, the chip is in a holding state.
The high-voltage isolating switch generally adopts an alternating current 220V motor to drive an operation structure through a connecting rod, the torque of the connecting rod operation structure can be reflected by the torque of a driving motor, and the torque of the motor has a certain corresponding relation with the working current of the motor. Taking an asynchronous motor as an example:
wherein: t is motor torque of the motor; kTIs a proportionality coefficient; phi is amIs an air gap flux; and I is the motor current.
When the torque T of the motor is increased, the current I is increased according to a formula, so that the current of the motor is driven by the operating mechanism, and the stress condition of the connecting rod of the operating mechanism can be reflected indirectly. Usually, rated current of a driving motor coil of the isolating switch operating mechanism is 1-2A, and instant starting current is larger when the driving motor is loaded, so that a 20A:1A current transformer is adopted to collect current of the driving motor coil, a current value is obtained, a current-time curve is drawn, and whether faults such as jamming, disconnecting switch operating mechanism rod breaking, disconnecting switch knife edge switching-in failure and the like exist in the GIS high-voltage isolating switch operating mechanism or not can be judged according to the current-time curve.
For example, if the current-time curve drawn during monitoring deviates from and is higher than the standard current-time curve, the phenomenon of jamming of the isolating switch operating mechanism is indicated; if the current-time curve drawn during monitoring disappears, the phenomenon of disconnection of a motor coil of the isolating switch operating mechanism is indicated; if the current at a certain point of a current-time curve drawn during monitoring is larger than a set value, the phenomenon that the isolating switch operating mechanism is jammed at the point or the mechanism is broken and locked is indicated; if the current at a certain point of a current-time curve drawn during monitoring is smaller than a set value, the phenomenon that the operating mechanism of the isolating switch breaks at the point is indicated, and the running resistance of the connecting rod is reduced; if the current of the current-time curve drawn during monitoring fluctuates, the phenomenon that the quality of the electric energy of the power supply of the driving motor of the disconnecting switch operating mechanism is poor or the operating mechanism looses or the transmission shaft sleeve cracks is shown; if the current of the current-time curve drawn during monitoring enters the knife edge part and the current is not changed, the knife edge of the moving contact and the static contact of the isolating switch deviates, and the phenomenon that the isolating switch mechanism is not in place to be separated and combined occurs; if the current of the current-time curve drawn during monitoring enters the knife edge part and the current increasing part is shortened, the contact area of the knife edge of the moving contact and the static contact of the isolating switch is reduced, and the phenomenon of poor contact of the isolating switch occurs.
The disconnecting switch operating mechanism usually rotates, the rotating angle and the position correspond to the rotating angle and the position of the driving motor one by one, and the disconnecting switch position state can be indirectly obtained through the rotating angle of the driving motor of the operating mechanism. Therefore, the angular displacement sensor is fixed on the rotating shaft of the driving motor, the rotating angle and the position of the operating mechanism can be indirectly obtained by using the angular displacement sensor, and the position of the isolating switch can be accurately judged to be an isolating position, a grounding position or a middle position according to data collected by the angular displacement sensor. And when the rotation angle of the operating mechanism is compared with the calibrated value of the rotation angle in commissioning and exceeds the set threshold value, the operating mechanism is indicated to be in fault.
In order to improve the security of monitoring, prevent the erroneous judgement, the utility model provides an utilize the verification mode that two kinds of methods combined together to carry out fault diagnosis. One method is to judge whether the operation mechanism of the isolating switch is in fault according to a current-time curve, and the other method is to judge whether the operation mechanism is in fault according to an angle and time, only if the judgment information of the two is consistent, the monitoring is confirmed to be completely correct, and if the judgment information of the two is inconsistent, the judgment is needed to be carried out again or the on-site inspection is needed.
As a preferred embodiment of the present invention, as shown in fig. 4, the apparatus further includes: and the storage unit is connected with the microprocessor unit and used for storing the current when the motor works, the rotating angle of the motor and the online monitoring result, and the storage unit adopts a storage chip MB85RC 64V.
In order to store current historical data and the like, the monitoring device selects a ferroelectric memory chip MB85RC64V, the maximum read-write frequency of the chip can reach 10 hundred million times, compared with the storage space of a microprocessor, the monitoring device has great advantages, the monitoring device can run for at least 10 years in a temperature test environment of 55 ℃, the working temperature of the monitoring device is-40-80 ℃, and the monitoring device can completely cope with the temperature of most regions in China, the MB85RC64V memory chip adopts an SOP8 packaging design, adopts an IIC communication mode to carry out data communication with the microprocessor, the maximum communication frequency is 400kHz, the working current is 0.15mA, the standby current is 5uA, the power consumption is low, the working voltage is 2.7-3.3V, and in order to ensure that two data lines of the IIC can stably transmit data, pull-up resistors are respectively connected to two ends of the SDA and the SC L during design, and the reliability of signals is ensured.
As a preferred embodiment of the present invention, as shown in fig. 5, the apparatus further includes: and one end of the communication unit is connected with the microprocessor unit, the other end of the communication unit is communicated with the background data management center, and the communication unit adopts an RS485 communication unit.
In order to realize the real-time monitoring of the running state of the device, the monitoring system sends the data of the lower computer to the upper computer through the RS485 communication unit for real-time monitoring. The RS485 communication unit adopts differential signal data transmission, and a commonly used two-wire system data transmission mode is used for representing transmission logic data through the level difference of two transmission lines. Assuming that the A, B level is VA and VB, respectively, when VA-VB is more than or equal to 0.2V, a logic 1 is represented, and when VA-VB is more than or equal to-0.2V, a logic 0 is represented. The circuit schematic diagram of the RS485 communication unit is shown in fig. 6, and includes an RS485 chip U9, resistors R31, R35, R45, and a transient suppression diode D5. The RS485 communication unit adopts twisted pair to transmit data, the characteristic impedance of the twisted pair is 120 omega, therefore, 120 omega impedance matching resistance R35 is connected in parallel at the output end, the signal reflection can be reduced, and the signal intensity can be increased. The interference in field use is large, therefore, the transient suppression diode D5 is added at the output end to absorb the surge current, and the protection circuit operates stably.
As a preferred embodiment of the present invention, as shown in fig. 7, the apparatus further includes: and the address selection unit is connected with the microprocessor unit, adopts a 12-bit dial switch and is used for selecting and setting the address of the high-voltage isolating switch.
As a preferable example of this embodiment, as shown in fig. 8, the apparatus further includes: and the display unit is connected with the microprocessor unit and is used for displaying the online monitoring result.
Preferably, the microprocessor unit is an STM32 microprocessor.
Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.
Claims (10)
1. High voltage isolator operating device mechanical properties on-line monitoring device, its characterized in that includes:
a current acquisition circuit, the current acquisition circuit comprising: the current transformer U1, diodes D1, D2, D3, D4, capacitors C1, C2 and a sampling resistor R1, wherein the current transformer U1 passes through any power line of a motor working power supply and is used for measuring current when the motor works, the anode of the diode D1 is connected with a common ground, the cathode of the diode D1 is connected with the second end of the current transformer U1 and the anode of the diode D2, the cathode of the diode D2 is connected with the cathode of the diode D4, one end of the capacitor C1, one end of the capacitor C2, one end of the sampling resistor R1 and a voltage collecting end, the anode of the diode D4 is connected with the cathode of the diode D3 and the first end of the current transformer, the anode of the diode D3 is connected with the common ground, the other end of the capacitor C1 is connected with the common ground, the other end of the capacitor C2 is connected with the common ground, and the other end of the sampling resistor R1 is connected with the common ground;
the angular displacement sensor is fixed on the output shaft of the motor, rotates along with the main shaft of the motor and is used for measuring the rotation angle of the motor;
and the microprocessor unit is connected with the current transformer and the angular displacement sensor and is used for realizing online monitoring on the mechanical characteristics of the high-voltage isolating switch operating mechanism according to the current of the motor during working and the rotation angle of the motor.
2. The on-line monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to claim 1, wherein the current collecting circuit further comprises:
and the signal high-speed acquisition circuit is connected with the voltage acquisition end and is used for acquiring current signals at a high speed.
3. The on-line monitoring device for mechanical characteristics of the operating mechanism of the high-voltage isolating switch as recited in claim 2, wherein the signal high-speed acquisition circuit adopts a high-speed acquisition chip AD 9226.
4. The on-line monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to claim 1, further comprising: and the storage unit is connected with the microprocessor unit and is used for storing the current of the motor during working, the rotating angle of the motor and the online monitoring result.
5. The on-line monitoring device for mechanical characteristics of the operating mechanism of the high-voltage isolating switch as claimed in claim 4, wherein the memory unit is a memory chip MB85RC 64V.
6. The on-line monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to claim 1, further comprising: one end of the communication unit is connected with the microprocessor unit, and the other end of the communication unit is communicated with the background data management center.
7. The device for on-line monitoring of the mechanical characteristics of the operating mechanism of the high-voltage isolating switch as claimed in claim 6, wherein the communication unit is an RS485 communication unit.
8. The on-line monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to claim 1, further comprising: and the address selection unit is connected with the microprocessor unit, adopts a 12-bit dial switch and is used for selecting and setting an address.
9. The on-line monitoring device for mechanical characteristics of an operating mechanism of a high-voltage isolating switch according to claim 1, further comprising: and the display unit is connected with the microprocessor unit and is used for displaying the online monitoring result.
10. The device for on-line monitoring of the mechanical characteristics of the operating mechanism of the high-voltage isolating switch according to any one of claims 1 to 9, wherein the microprocessor unit adopts an STM32 microprocessor.
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| CN201921626690.6U CN211085641U (en) | 2019-09-27 | 2019-09-27 | Mechanical characteristic on-line monitoring device for high-voltage isolating switch operating mechanism |
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| CN201921626690.6U CN211085641U (en) | 2019-09-27 | 2019-09-27 | Mechanical characteristic on-line monitoring device for high-voltage isolating switch operating mechanism |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112710951A (en) * | 2020-12-16 | 2021-04-27 | 国网江苏省电力有限公司检修分公司 | GIS isolator state determination system |
| CN113533841A (en) * | 2021-06-08 | 2021-10-22 | 云南电网有限责任公司红河供电局 | Non-invasive detection method for power of high-voltage isolating switch driving motor |
-
2019
- 2019-09-27 CN CN201921626690.6U patent/CN211085641U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112710951A (en) * | 2020-12-16 | 2021-04-27 | 国网江苏省电力有限公司检修分公司 | GIS isolator state determination system |
| CN112710951B (en) * | 2020-12-16 | 2024-03-12 | 国网江苏省电力有限公司检修分公司 | GIS isolating switch state determining system |
| CN113533841A (en) * | 2021-06-08 | 2021-10-22 | 云南电网有限责任公司红河供电局 | Non-invasive detection method for power of high-voltage isolating switch driving motor |
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