CN118169553A - Device and method for diagnosing switching-on resistance state of high-voltage circuit breaker - Google Patents

Abstract

The invention discloses a device and a method for diagnosing a closing resistance state of a high-voltage circuit breaker, wherein the device comprises a differential pressure acquisition module: the method is used for acquiring the pressure difference of two ends of a main loop of the high-voltage circuit breaker when the closing resistor is thrown; a current acquisition module: the method comprises the steps of acquiring a main loop closing current of a high-voltage circuit breaker; intelligent diagnosis module of high-voltage circuit breaker: and the resistor dynamic waveform is used for diagnosing the state of the closing resistor according to the voltage difference value and the current value in the closing resistor input time, the duration and the duration period. The invention synchronously collects the current waveform of the main loop and the voltage waveforms of the two ends of the main loop of the high-voltage circuit breaker by using the distributed monitoring device, and provides data support for fault diagnosis under the operating condition of the circuit breaker; automatically calculating the switching-on input resistance, the switching-on resistance input time and the duration of the circuit breaker, and realizing intelligent detection of the running state of the high-voltage circuit breaker; and analyzing the switching-on state change of the high-voltage circuit breaker to form a characteristic database, and providing fault early warning for the whole-service-life operation of the high-voltage circuit breaker.

Description

Device and method for diagnosing switching-on resistance state of high-voltage circuit breaker

Technical Field

The invention belongs to the technical field of intelligent instruments and meters, and particularly relates to a device and a method for diagnosing a closing resistance state of a high-voltage circuit breaker.

Background

The long-distance ultra-high voltage transmission line has complex running environment, the no-load line has serious overvoltage closing, and in order to limit the overvoltage of the closing line, a parallel closing resistor is arranged on the circuit breaker to be used as a main measure for limiting the overvoltage of the closing line. Due to the effects of the circuit breaker manufacturing process, inherent characteristics of a moving mechanism and the like, the breakdown and the burnout of the switching-on resistor occur under the over-voltage and over-current effects, so that the main transmission network is frequently disconnected and is withdrawn from operation, and the safe and stable operation of the ultra-high voltage circuit is seriously endangered.

At present, a high-voltage circuit breaker is usually overhauled under power failure, and because the power failure state of the circuit breaker is greatly different from the operation working condition, the switching-on fault of the circuit breaker is usually easier to occur under the working conditions such as overvoltage, overcurrent and the like. The existing high-voltage circuit breaker monitoring device has single function, most systems are only limited in researching the mechanical performance of the circuit breaker, and lack of systematic and comprehensive functional modules for monitoring the circuit breaker, and meanwhile, no effective mathematical method and technical means are available for intelligently diagnosing the closing operation state of the circuit breaker. Therefore, the existing high-voltage circuit breaker monitoring method cannot be directly applied to the high-voltage circuit breaker closing resistance diagnosis project.

Disclosure of Invention

In order to detect the switching-on resistance state of a high-voltage circuit breaker in a switching-on running state of the circuit breaker, the invention provides a device and a method for diagnosing the switching-on resistance state of the high-voltage circuit breaker.

The invention provides a device for diagnosing the closing resistance state of a high-voltage circuit breaker, which comprises:

differential pressure acquisition module: the method comprises the steps of acquiring the voltage difference of the voltages at two ends of a main loop of a high-voltage circuit breaker when a closing resistor is switched in;

A current acquisition module: the method comprises the steps of acquiring a main loop closing current of a high-voltage circuit breaker;

intelligent diagnosis module of high-voltage circuit breaker: the method is used for calculating according to the differential pressure value acquired from the differential pressure acquisition module and the current value of the switching-on current acquired from the current acquisition module, obtaining the dynamic waveforms of the resistors in the input time, the duration and the duration of the switching-on resistor, and diagnosing the state of the switching-on resistor according to the dynamic waveforms of the resistors in the input time, the duration and the duration of the switching-on resistor.

The switching-on resistor has the following investment duration: the time period from the starting of the pressurization of the closing coil of the high-voltage circuit breaker control mechanism to the occurrence of the jump of the main loop current;

The duration of the closing resistor is as follows: the time from when the jump of the main loop current starts to when the voltages at the two sides of the high-voltage circuit breaker are the same;

The duration time period of the closing resistor is as follows: and a time period corresponding to the duration of the closing resistor.

Further, the intelligent diagnosis module of the high-voltage circuit breaker further comprises a current range automatic selection module, a proper current sensor is selected according to the current of the main circuit of the circuit breaker, when the circuit is in idle closing, a current signal is small, and the current signal output by the current sensor at the side of the circuit is automatically selected as the closing current of the main circuit; when the circuit is in short circuit closing, the current signal is large, and the current signal output by the bus side current sensor is selected as the main loop closing current. The above measures solve the requirements of high-precision and wide-range detection of circuit current signals of the circuit breaker.

Further, the method further comprises the following steps:

Bus side signal acquisition and data remote transmission module: the intelligent diagnosis module is used for collecting the switching-on current of the main circuit at the bus side and the voltage at the bus side and transmitting the switching-on current and the voltage to the intelligent diagnosis module of the high-voltage circuit breaker;

line side signal acquisition and data remote transmission module: and the intelligent diagnosis module is used for collecting the line-side main loop closing current and the bus-side voltage and transmitting the current and the bus-side voltage to the intelligent diagnosis module of the high-voltage circuit breaker.

Further, the circuit breaker further comprises a switching-on coil triggering module, wherein the switching-on coil triggering module is used for converting voltage signals at two ends of a switching-on coil in the high-voltage circuit breaker into signals for controlling interruption triggering of a bus side signal acquisition and data remote transmission module and a processor in a line side signal acquisition and data remote transmission module. The measures ensure that the data collected by different devices are kept synchronous in time, and the deviation of the calculation of the closing resistance caused by sampling time difference is eliminated.

Further, the intelligent diagnosis module of the high-voltage circuit breaker comprises a switching-on resistor fault diagnosis module, wherein the switching-on resistor fault diagnosis module is used for comparing the switching-on resistor resistance value in the duration time period of the switching-on resistor with a set resistance value fluctuation interval, and when the switching-on resistor resistance value is not in the set resistance value fluctuation interval, the state of the switching-on resistor is considered to be abnormal; the set resistance fluctuation interval is a resistance fluctuation interval of the high-voltage circuit breaker in the full temperature range.

Further, the intelligent diagnosis module of the high-voltage circuit breaker comprises an action characteristic diagnosis module which is used for monitoring the switching-on duration and the duration of the switching-on resistor of the high-voltage circuit breaker, and if the switching-on duration or the duration of the switching-on resistor is not in the action characteristic time fluctuation range of the high-voltage circuit breaker, the state of the switching-on resistor is considered to be abnormal.

The action characteristic time fluctuation range of the high-voltage circuit breaker is used for judging whether the input time and the duration of the closing resistor are in a normal time range, and the input time is too short or too long, and the duration is too short or too long, so that the state of the closing resistor is considered to be abnormal.

Further, the bus side signal acquisition and data remote transmission module and the line side signal acquisition and data remote transmission module both comprise clock modules for clock synchronization.

Further, the device also comprises a switching-on resistor input time point identification module, wherein the switching-on resistor input time point identification module is used for dividing the collected current data into a plurality of sections at average intervals, sequentially carrying out difference value calculation on the data of the next section and the data of the previous section, and identifying the abrupt change point of the current waveform when the auxiliary fracture of the high-voltage circuit breaker is switched on according to the difference value and the trigger threshold value, wherein the abrupt change point corresponds to the switching-on resistor input time point of the high-voltage circuit breaker.

The second object of the invention is achieved by a method for diagnosing the state of the closing resistance of a high-voltage circuit breaker, comprising the following steps:

Acquiring the pressure difference of two ends of a main loop of the high-voltage circuit breaker when the closing resistor is thrown;

acquiring a switching-on current of a main loop of the high-voltage circuit breaker;

Calculating according to the differential pressure value and the current value to obtain the input duration, the duration and the resistance dynamic waveform in the duration period of the closing resistor; the duration time period is a time period corresponding to the duration time of the switching-on resistor;

And diagnosing the state of the closing resistor according to the input time, the duration and the dynamic waveform of the resistor in the duration period of the closing resistor.

Further, when the line is in idle-load closing, a current signal output by a line side current sensor is selected as main loop closing current; when the circuit is in short circuit switching-on, a current signal output by the bus side current sensor is selected as a main loop switching-on current.

Further, collecting the bus side main loop closing current and the bus side voltage; and collecting the line-side main loop closing current and the line-side voltage.

Further, the method also comprises the step of converting voltage signals at two ends of a closing coil in the high-voltage circuit breaker into signals for controlling processor interruption triggering of bus side signal acquisition and line side signal acquisition.

Further, the judging method for the abnormal state of the closing resistor comprises the following steps: comparing the resistance value of the closing resistor in the duration time period of the closing resistor with the resistance value fluctuation range of the full temperature range of the high-voltage circuit breaker, and considering that the state of the closing resistor is abnormal when the resistance value of the closing resistor is not in the resistance value fluctuation range of the full temperature range of the high-voltage circuit breaker; the duration time period of the closing resistor is as follows: the main circuit of the high-voltage circuit breaker has the same time period from the current to the voltage at the two sides of the high-voltage circuit breaker.

Further, the judging method for the abnormal state of the closing resistor further comprises the following steps: when the input duration or the duration of the switching-on resistor is not in the fluctuation range of the action characteristic time of the high-voltage circuit breaker, the state of the switching-on resistor is considered to be abnormal; the switching-on resistor has the following investment duration: a time period from the start of pressurization of the closing coil of the high-voltage circuit breaker control mechanism to the occurrence of jump of the main loop current; the duration of the closing resistor is as follows: the main loop current transitions to the same period of time as the voltage across the high voltage circuit breaker.

Still further, the method of determining the closing resistance duration includes:

Dividing the average interval of the collected current data into a plurality of sections, sequentially carrying out difference value calculation on the data of the next section and the data of the previous section, and identifying a mutation point of a current waveform when the auxiliary break of the high-voltage circuit breaker is switched on according to the difference value and a trigger threshold value, wherein the mutation point corresponds to the switching-on resistance input time T _{Starting point} of the high-voltage circuit breaker;

The time of synchronization of the phase amplitude of the bus voltage waveform and the line side voltage waveform is used as the main break closing time T _{closing switch} of the high-voltage breaker;

switching-on resistor duration T _{Duration of time} ＝(T _{closing switch} -T _{Starting point} ) x sampling rate

The closing resistance duration period is a period from the start of T _{Starting point} to the end of T _{closing switch} .

Further, the method for obtaining the closing resistance in the closing resistance input duration time period comprises the following steps:

acquiring loop current waveform data I _{Loop circuit} , bus side voltage waveform data U _{Bus side} and line side voltage waveform data U _{Line side} acquired by each sampling point in the switching-on resistor input duration period; and calculating a closing resistor R _{closing switch} corresponding to each sampling time according to the following formula:

R _{closing switch} ＝(|U _{Bus side} -U _{Line side} |)/|I _{Loop circuit} |。

a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, performs any of the steps of the method of diagnosing a state of a closing resistance of a high voltage circuit breaker.

The beneficial effects of the invention include:

(1) The distributed monitoring device is utilized to synchronously acquire the current waveform of the main loop of the high-voltage circuit breaker and the voltage waveform of the two ends of the main loop of the high-voltage circuit breaker at high speed, in a wide range and high precision, so as to provide data support for fault diagnosis under the operating condition of the circuit breaker;

(2) The method comprises the steps of adopting algorithms such as switching-on current waveform mutation point identification, signal recursion sampling and the like to automatically calculate switching-on input resistance, switching-on resistance input time and duration of the circuit breaker, and realizing intelligent detection of the running state of the high-voltage circuit breaker;

(3) And analyzing the switching-on state change of the high-voltage circuit breaker to form a characteristic database, and providing fault early warning for the whole-service-life operation of the high-voltage circuit breaker.

Drawings

FIG. 1 is a schematic view of the structure of the device of the present invention;

Wherein: the intelligent diagnosis system comprises a 1-switching-on coil triggering module, a 2-bus side voltage sensor, a 3-bus side current sensor (short-circuit current), a 4-line side voltage sensor, a 5-line side current sensor (no-load current), a 6-bus side signal acquisition and data remote transmission module, a 7-line side signal acquisition and data remote transmission module and an 8-high-voltage circuit breaker intelligent diagnosis module;

fig. 2 is a high voltage circuit breaker voltage and current measurement point layout.

Detailed Description

The following detailed description is presented to explain the claimed invention and to enable those skilled in the art to understand the claimed invention. The scope of the invention is not limited to the following specific embodiments. It is also within the scope of the invention to include the claims of the present invention as made by those skilled in the art, rather than the following detailed description.

Fig. 1 shows an embodiment of a device for diagnosing a closing resistance state of a high-voltage circuit breaker, which comprises a closing coil triggering module 1, a bus side voltage sensor 2, a bus side current sensor 3, a line side voltage sensor 4, a line side current sensor 5, a bus side signal acquisition and data remote transmission module 6, a line side signal acquisition and data remote transmission module 7 and a high-voltage circuit breaker intelligent diagnosis module 8.

The switching-on coil triggering module 1 converts voltage signals at two ends of a switching-on coil in a high-voltage circuit breaker control mechanism into signals for controlling interruption triggering of a bus side signal acquisition and data remote transmission module 6 and a circuit side signal acquisition and data remote transmission module 7 processor, and is provided with a filtering, anti-shake and photoelectric conversion circuit, so that a photoelectric synchronous pulse signal can be output.

The bus side voltage sensor 2 collects bus voltage from a high-voltage circuit breaker bus side capacitance type voltage transformer, and the circuit breaker bus voltage is restored with high precision by utilizing a V/I and I/V conversion circuit;

The bus side current sensor 3 collects current signals from the secondary side of the bus side current transformer of the high-voltage circuit breaker by using the core penetration CT, and high-precision short-circuit current signals of the main loop of the high-voltage circuit breaker are restored by using the I/V conversion circuit.

The line-side voltage sensor 4 collects line voltage from a high-voltage circuit breaker line-side capacitive voltage transformer, and high-precision circuit breaker line-side voltage is restored by using a V/I and I/V conversion circuit.

The line side current sensor 5 collects current signals from the secondary side of the line side current transformer of the high-voltage circuit breaker by using the core penetration CT, and restores the no-load current signals of the main loop of the high-voltage circuit breaker with high precision through the I/V conversion circuit.

The bus side voltage sensor 2 and the line side voltage sensor 4 are used for sampling the voltage difference between two ends of a main loop of the high-voltage circuit breaker when the switching-on resistor is switched on. The bus side current sensor 3 covers the short-circuit current range of the main circuit of the circuit breaker, the line side current sensor 5 covers the no-load current range of the main circuit of the circuit breaker, and the two current sensors cover the normal running current range at the same time; the device automatically selects current data with high acquisition precision to execute calculation according to the interval division of the actually measured current value, and specifically comprises the following steps: when the line is in idle-load closing, the sampling signal of the bus side current sensor 3 is too small, and at the moment, the intelligent diagnosis module 8 of the circuit breaker selects the current data of the line side current sensor 5 to be substituted into calculation; when the line is short-circuited and closed, the line side current sensor 5 is saturated and distorted, and at the moment, the intelligent diagnosis module 8 of the circuit breaker selects the current data of the bus side current sensor 3 to be substituted into calculation. By reasonably dividing the current measurement interval, the intelligent diagnosis module 8 of the circuit breaker automatically selects the current data with high acquisition precision to be substituted into calculation.

The bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7 trigger synchronous acquisition by photoelectric pulses output by the switching-on coil triggering module 1, synchronously sample the switching-on current of a main loop of 100ms, the bus side voltage and the line side voltage at a sampling rate of 10 mu s, and store monitoring data packets into an internal FLASH according to the acquisition time sequence; the bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7 are integrated with Beidou and GPS clocks, clock synchronization is kept by utilizing received satellite signals, and synchronous acquisition is executed at regular time intervals at ordinary times for checking the running state of a main circuit of the high-voltage circuit breaker.

The intelligent diagnosis module 8 of the high-voltage circuit breaker queries working states of the bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7 at regular time, receives acquired current and voltage waveform data packets, and finds out current closing points of an auxiliary fracture and a main fracture of the high-voltage circuit breaker by utilizing algorithms such as mutation point identification and signal recurrence sampling; performing difference operation on the bus side voltage waveform and the line side voltage waveform to obtain voltage waveforms at two ends of a closing resistor in the reclosing process of the circuit breaker; dividing the voltage waveform value at two ends of the resistor at the same time by the current waveform value to obtain the resistor value at the same time; and sequentially calculating a waveform sequence of the duration time period of the closing resistor to obtain a resistor waveform sequence and a resistance change trend in the reclosing process, and further analyzing the change relation of the resistance of the closing resistor along with time in the whole pre-input period.

The switching-on coil triggering module 1 is connected with the bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7; the bus side voltage sensor 2 and the bus side current sensor 3 are connected with a bus side signal acquisition and data remote transmission module 6; the line side voltage sensor 4 and the line side current sensor 5 are connected with the line side signal acquisition and data remote transmission module 7; the bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7 are connected with the high-voltage circuit breaker intelligent diagnosis module 8 by utilizing a wired or wireless network.

As shown in fig. 2, a voltage and current measuring point layout diagram of a high-voltage circuit breaker is shown, wherein a main loop in the high-voltage circuit breaker comprises a main fracture, an auxiliary fracture and a closing resistor, and the auxiliary fracture and the closing resistor are connected in series and then connected with the main fracture in parallel; the bus-side ammeter A1 corresponds to the bus-side current sensor 3; the line-side ammeter A2 corresponds to the line-side current sensor 5; the busbar side voltmeter Ua corresponds to the busbar side voltage sensor 2; the line-side voltmeter Ub corresponds to the line-side voltage sensor 4. The switching-on coil triggering module 1 is arranged near a switching-on coil of the high-voltage circuit breaker control mechanism; the bus side signal acquisition and data remote transmission module 6 and the line side signal acquisition and data remote transmission module 7 are arranged near the high-voltage circuit breaker; the intelligent diagnosis module 8 of the high-voltage circuit breaker is arranged in a main control room of the transformer substation.

The intelligent diagnosis module 8 of the high-voltage circuit breaker analyzes the waveform data as follows.

Step one: firstly, the point number T _{Starting point} ,T _{Starting point} of the current waveform abrupt change point when the auxiliary break of the high-voltage circuit breaker is switched on is found from the collected 100ms long-duration current waveform, and the switching-on resistance input time of the high-voltage circuit breaker corresponds to the sampling rate (10 mu s in the embodiment).

The specific algorithm is as follows: when the sampling rate is 10 mu s, the number of corresponding acquisition points of a 100ms current waveform is 10000 points, the 100ms current waveform is divided into 100 sections 1# to 100# at 1ms intervals, and difference value calculation is carried out on 100 point data of a later section (such as 2# and the like) and 100 point data of a previous section (such as 1# and the like) from a starting point to an end point to obtain a plurality of difference values; comparing each difference value with a set difference value trigger threshold (such as 0.2A), adding 1 to a counter when the difference value is larger than the trigger threshold, and considering that the corresponding acquisition time point is the point number T _{Starting point} of the current waveform mutation point when the auxiliary fracture of the high-voltage circuit breaker is closed when the count value is larger than a set value (such as 20); such as: the number of waveform segments (such as 2#) is larger than the set value when the number of corresponding points (10 th point) is counted, and then the number of starting points of current waveform closing is: 2 x 100+10=210 points, 210 points being defined as T _{Starting point} . The setting reference current sensor zero drift fluctuation of the difference trigger threshold value is larger than the number of continuous flying points of the waveform under the interference condition.

Step two: the closing time of the main break of the high-voltage circuit breaker is the time when the phase amplitude of the bus-side voltage waveform and the phase amplitude of the line-side voltage waveform are synchronous, and the closing current point T _{closing switch} of the main break of the high-voltage circuit breaker is found according to the rule, so that the duration of the closing resistor is calculated as follows:

T _{Duration of time} ＝(T _{closing switch} -T _{Starting point} )*10μs。

Step three: dividing the voltage drop waveform data of the closing resistance duration time period (namely the time period from T _{Starting point} to T _{closing switch} ) by the loop current waveform data at the same moment to obtain the dynamic waveform of the resistance in the closing resistance duration time period.

The specific algorithm is as follows: obtaining loop current waveform data, bus side voltage waveform data U _{Bus side} and line side voltage waveform data U _{Line side} of a closing resistor duration period according to T _{Starting point} and T _{closing switch} ; subtracting the line side voltage waveform data U _{Line side} from the bus side voltage waveform data U _{Bus side} to obtain voltage drop waveform data of two ends of the closing resistor; and dividing the voltage drop data (U _{Bus side} -U _{Line side} ) at two ends of the simultaneous switching-on resistor by the absolute value data (I _{Loop circuit} ) of the simultaneous loop current to obtain the resistance value at the moment, wherein R _{closing switch} ＝(|U _{Bus side} -U _{Line side} |)/|I _{Loop circuit} is the same.

Preferably, when |i _{Loop circuit} | or |u _{Bus side} -U _{Line side} | is 0, the average value of the switching-on resistance values sampled at the first stage (e.g., 1ms before zero crossing) and the second stage (e.g., 1ms after zero crossing) of the zero crossing of the voltage and current waveform data is taken as the resistance value at the position of the zero crossing, and the problem that the switching-on resistance value cannot be obtained through U/I is eliminated when the voltage and the current are zero. And obtaining the dynamic waveform of the resistor in the duration time period of the closing resistor according to the steps.

When the internal resistance value of the high-voltage circuit breaker switching-on resistor is relatively stable in a certain temperature range, and if the resistance value in a waveform sequence of the detected switching-on resistor R _{closing switch} is 40% smaller than the switching-on resistor data of the high-voltage circuit breaker in factory delivery and power failure maintenance, judging that a part of switching-on resistor string in the internal switching-on resistor of the circuit breaker is bypassed; if the detected switching-on resistance R _{closing switch} approaches 0 when the switching-on resistance is pre-input for 9ms, the actual input of the switching-on resistance is 9ms.

The intelligent diagnosis module of the high-voltage circuit breaker also provides a fault diagnosis function, and specifically comprises the following steps: fault diagnosis, action characteristic diagnosis and fault mode identification of the closing resistor;

the method for diagnosing the switching-on resistor faults of the high-voltage circuit breaker comprises the following steps:

And setting a resistance fluctuation interval of the full temperature range of the high-voltage circuit breaker according to the switching-on resistance data of the high-voltage circuit breaker when leaving a factory and carrying out power failure maintenance, and prompting maintenance when the switching-on resistance R _{closing switch} detected on line is not in the resistance fluctuation interval of the full temperature range of the high-voltage circuit breaker. The switching-on resistance data of the high-voltage circuit breaker in factory and power failure maintenance can be obtained from manufacturers. When the circuit breaker is subjected to power failure maintenance, a transformer operation and maintenance person periodically tests the switch-on resistance of the circuit breaker, so that the switch-on resistance can be obtained from a transformer operation and maintenance department.

The method for diagnosing the action characteristics of the high-voltage circuit breaker comprises the following steps:

and if the input duration of the switching-on resistor is not in the set fluctuation range of the action characteristic time of the high-voltage circuit breaker or the duration of the switching-on resistor is not in the set fluctuation range of the action characteristic time of the high-voltage circuit breaker, the state of the switching-on resistor is considered to be abnormal. The switching-on resistor has the following input time period: the time period corresponding to the input time of the switching-on resistor; the duration time period of the closing resistor is as follows: and a time period corresponding to the duration of the closing resistor.

The set action characteristic time fluctuation range of the high-voltage circuit breaker is set according to the input time period and the data in the duration time period of the closing resistor obtained from the delivery and the power failure maintenance of the high-voltage circuit breaker, the step is used for judging whether the input time period and the duration time period of the closing resistor are in a reasonable range or not, the reasonable range is usually in a millisecond level, such as 8-12 ms, and if the duration time period is not in the reasonable range, the state of the closing resistor is considered to be abnormal.

When the input duration or duration T _{Duration of time} of the switching-on resistor is not in the set fluctuation range of the action characteristic time of the high-voltage circuit breaker, prompting that maintenance is needed.

The fault mode identification method of the high-voltage circuit breaker comprises the following steps:

Storing switching-on resistance waveform data under various fault states in a fault characteristic database of the circuit breaker, wherein an acquisition channel of the data comprises: building a test platform at a manufacturer of the high-voltage circuit breaker, simulating multiple faults of the high-voltage circuit breaker, and obtaining fault waveform data; comparing the resistance dynamic waveform of the on-line monitored closing resistor with waveforms in a characteristic database, and analyzing the fault mode of the high-voltage circuit breaker, for example, analyzing the waveform consistency by adopting Euler's law; failure modes such as high voltage circuit breaker mechanical failure and electrical failure; different processing methods are adopted for different fault types. If the spring fails, the spring needs to be replaced and comprehensively checked, and if the closing resistor burns out, the high-voltage circuit breaker needs to be replaced.

The working principle and the function of the invention are realized

The working principle of the invention is as follows: as shown in fig. 2, the main circuit of the high-voltage circuit breaker is formed by connecting a main fracture circuit and an auxiliary fracture circuit in parallel, and the auxiliary fracture is connected with a closing resistor in series; when the high-voltage circuit breaker is switched on, the auxiliary fracture is switched on first, and then the main fracture is switched on.

According to ohm law R=U/I, the voltage U at two ends of the resistor and the current I flowing through the resistor are obtained, and the resistor R can be calculated.

The monitoring device synchronously collects PT voltage and CT current waveforms in real time, and can find out switching-on resistance input time T _{Starting point} and exit time T _{closing switch} from the waveform. The starting moment T _{Starting point} of closing is the current jump moment of the main loop; the time T _{closing switch} when the switching resistor is shorted is the time when the phase amplitude of the bus-side PT voltage waveform is synchronous with the phase amplitude of the line-side PT voltage waveform.

The management background obtains voltage waveforms at two ends of a closing resistor in the reclosing process of the circuit breaker through difference operation between a bus side PT voltage waveform Ua and a line side PT voltage waveform Ub; the resistance value at that time can be obtained by dividing the voltage waveform value at both ends of the resistor at that time by the current waveform value Ia.

And sequentially calculating a waveform sequence of the switching-on resistor in the switching-on period to obtain a resistor waveform sequence and a resistance change trend in the reclosing process, and further analyzing the change relation of the resistance of the switching-on resistor along with time in the whole pre-switching-on period.

The embodiment of the invention also comprises a method for diagnosing the state of the closing resistance of the high-voltage circuit breaker:

Acquiring the pressure difference of two ends of a main loop of the high-voltage circuit breaker when the closing resistor is thrown;

acquiring a switching-on current of a main loop of the high-voltage circuit breaker;

And calculating according to the differential pressure value and the current value to obtain a resistor dynamic waveform in the input time, the duration and the duration of the closing resistor, and diagnosing the state of the closing resistor according to the resistor dynamic waveform in the input time, the duration and the duration of the closing resistor.

In the method, when the line is in idle load closing, a current signal output by a line side current sensor is selected as main loop closing current; when the circuit is in short circuit switching-on, a current signal output by the bus side current sensor is selected as a main loop switching-on current.

The method further comprises the step of collecting the bus side main loop closing current and the bus side voltage; and collecting the line side main loop closing current and the bus side voltage.

The method further comprises the step of converting voltage signals at two ends of a closing coil in the high-voltage circuit breaker into signals for controlling processor interruption triggering of bus side signal acquisition and line side signal acquisition.

In the method, the judging method for the abnormal state of the closing resistor comprises the following steps: and comparing the resistance value of the closing resistor in the duration time period of the closing resistor with the resistance value fluctuation range of the full temperature range of the high-voltage circuit breaker, and considering that the state of the closing resistor is abnormal when the resistance value of the closing resistor is not in the resistance value fluctuation range of the full temperature range of the high-voltage circuit breaker.

In the method, the judging method for the abnormal state of the closing resistor further comprises the following steps: and respectively comparing the duration and the input duration of the switching-on resistor with the set duration fluctuation range of the high-voltage circuit breaker, and considering that the state of the switching-on resistor is abnormal when the input duration or the duration of the switching-on resistor is not in the action characteristic time fluctuation range of the high-voltage circuit breaker.

It should be understood that the sequence number of each step in the foregoing embodiment does not mean that the execution sequence of each process should be determined by the function and the internal logic, and should not limit the implementation process of the embodiment of the present application.

The embodiment of the present invention further provides a computer readable storage medium, where a computer program is stored, where the computer program includes program instructions, and when the program instructions are executed by a processor, the program instructions implement each step of the method of the present invention, which is not described herein.

The computer readable storage medium may be the data transmission apparatus provided in any of the foregoing embodiments or an internal storage unit of a computer device, for example, a hard disk or a memory of the computer device. The computer readable storage medium may also be an external storage device of the computer device, such as a plug-in hard disk, a smart memory card (SMART MEDIA CARD, SMC), a Secure Digital (SD) card, a flash memory card (FLASH CARD), etc. that are provided on the computer device.

Further, the computer-readable storage medium may also include both internal storage units and external storage devices of the computer device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium may also be used to temporarily store data to be output or already output.

It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

What is not described in detail in this specification is prior art known to those skilled in the art.

Claims (13)

1. A device for diagnosing a closing resistance state of a high voltage circuit breaker, comprising:

Differential pressure acquisition module: the method comprises the steps of acquiring a differential pressure value of voltages at two ends of a main loop of a high-voltage circuit breaker when a closing resistor is switched in;

A current acquisition module: the method comprises the steps of acquiring a main loop closing current of a high-voltage circuit breaker;

Intelligent diagnosis module of high-voltage circuit breaker: the voltage difference acquisition module is used for acquiring a voltage difference value of a switching-on resistor according to the voltage difference value of the switching-on resistor and the current value of the switching-on current; and diagnosing the state of the closing resistor according to the switching-in duration, the duration and the dynamic waveform of the resistor in the duration period.

2. The device for diagnosing a closing resistance state of a high-voltage circuit breaker according to claim 1, wherein the intelligent diagnosis module of the high-voltage circuit breaker further comprises a current range automatic selection module for selecting a current sensor according to the magnitude of a main loop current of the high-voltage circuit breaker; when the line is in idle-load closing, automatically selecting a current signal output by a line side current sensor as main loop closing current; when the circuit is in short circuit switching-on, a current signal output by the bus side current sensor is selected as a main loop switching-on current.

3. The apparatus for diagnosing a closing resistance state of a high voltage circuit breaker as claimed in claim 1, further comprising:

Bus side signal acquisition and data remote transmission module: the intelligent diagnosis module is used for collecting the switching-on current of the main circuit at the bus side and the voltage at the bus side and transmitting the switching-on current and the voltage to the intelligent diagnosis module of the high-voltage circuit breaker;

line side signal acquisition and data remote transmission module: and the intelligent diagnosis module is used for collecting the line-side main loop closing current and the bus-side voltage and transmitting the current and the bus-side voltage to the intelligent diagnosis module of the high-voltage circuit breaker.

4. The apparatus for diagnosing a closing resistance state of a high voltage circuit breaker as recited in claim 3, further comprising a closing coil triggering module for converting voltage signals across the closing coil in the high voltage circuit breaker into signals for controlling processor interrupt triggering in the bus side signal acquisition and data telemetry module and the line side signal acquisition and data telemetry module.

5. The apparatus for diagnosing a closing resistance state of a high voltage circuit breaker according to claim 1, wherein the intelligent diagnosis module of the high voltage circuit breaker comprises a closing resistance fault diagnosis module for comparing a closing resistance value in a closing resistance duration period with a set resistance value fluctuation interval, and considering that the closing resistance state is abnormal when the closing resistance value is not in the set resistance value fluctuation interval.

6. The apparatus for diagnosing a closing resistance state of a high voltage circuit breaker according to claim 1, wherein the intelligent diagnosis module of the high voltage circuit breaker comprises an action characteristic diagnosis module for monitoring a duration and a duration of a closing resistance of the high voltage circuit breaker, and considering that the closing resistance state is abnormal when the duration and duration of the closing resistance are not within a fluctuation range of an action characteristic time of the high voltage circuit breaker.

7. A method of diagnosing a closing resistance state of a high voltage circuit breaker, comprising:

Acquiring a differential pressure value of the voltage at two ends of a main loop of the high-voltage circuit breaker when the closing resistor is thrown;

acquiring a switching-on current of a main loop of the high-voltage circuit breaker;

Calculating according to the differential pressure value and the current value to obtain the input duration, the duration and the resistance dynamic waveform in the duration period of the closing resistor; and diagnosing the state of the closing resistor according to the input time, the duration and the dynamic waveform of the resistor in the duration period of the closing resistor.

8. The method for diagnosing a closing resistance state of a high voltage circuit breaker as recited in claim 7, wherein a current signal output from the line side current sensor is automatically selected as a main loop closing current when the line is closed with no load; when the circuit is in short circuit switching-on, a current signal output by the bus side current sensor is selected as a main loop switching-on current.

9. The method of diagnosing a closing resistance state of a high voltage circuit breaker as recited in claim 7, further comprising collecting a bus side main loop closing current and a bus side voltage; and collecting the line-side main loop closing current and the line-side voltage.

10. The method of diagnosing a closing resistance state of a high voltage circuit breaker as recited in claim 9, further comprising converting a voltage signal across a closing coil in the high voltage circuit breaker into a signal for processor interrupt triggering controlling bus side signal acquisition and line side signal acquisition.

11. The method for diagnosing a closing resistance state of a high voltage circuit breaker as claimed in claim 7, wherein the judging method of the closing resistance state abnormality comprises: and comparing the resistance value of the switching-on resistor in the continuous time period of the switching-on resistor with a set resistance value fluctuation interval, and considering that the state of the switching-on resistor is abnormal when the resistance value of the switching-on resistor is not in the set resistance value fluctuation interval.

12. The method for diagnosing a closing resistance state of a high voltage circuit breaker as claimed in claim 7, wherein the judging method of the closing resistance state abnormality comprises: and when the switching-on resistance input duration or the duration is not in the fluctuation range of the action characteristic time of the high-voltage circuit breaker, the state of the switching-on resistance is considered to be abnormal.

13. A non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor, implements the steps of the method of diagnosing a high voltage circuit breaker closing resistance status as claimed in any one of claims 1 to 6.