A judgment device and judgment method for judging the working position of a circuit breaker

Abstract

The present invention belongs to the technical field of medium voltage power supply for nuclear power plants, and specifically relates to a judgment device and a judgment method for judging the working position of a 6kV circuit breaker in a nuclear power plant, comprising: auxiliary circuit breaker contacts, a circuit breaker, a resistor, an instrumentation module, a signal screen display, an OR gate negation logic module, an alarm screen display, a cable and a power supply module; the present invention unifies the judgment method of whether a 6kV circuit breaker is in the working position, and at the same time adds a monitoring and alarm function for the working position of the 6kV circuit breaker, thereby providing a powerful guarantee means for operating personnel to monitor whether the circuit breaker is in the working position.

Description

Technical Field

[0001] The present invention belongs to the technical field of medium voltage power supply for nuclear power plants, and in particular relates to a judging device and a judging method for judging the working position of a 6kV circuit breaker of a nuclear power plant. Background Art

[0002] In the process of producing electricity in nuclear power plants, there are a large number of mechanical equipment driven by motors to ensure the normal operation of main equipment and auxiliary equipment such as reactors, steam turbines, generators, etc. At the same time, there are also electrical equipment and systems that provide reliable power supply for nuclear safety-related equipment to achieve reactor safety under nuclear accident conditions. The above electrical equipment and systems are collectively referred to as the power supply system of nuclear power plants. The 6kV medium-voltage system for power supply of nuclear power plants is equipped with a large number of circuit breakers to provide power to equipment such as pumps, fans, and dry-type transformers in nuclear power plants.

[0003] When the 6kV circuit breaker in the prior art is in power transmission operation, after the trolley circuit breaker is swung from the "test position" to the "working position", since the circuit breaker cabinet body is not provided with an obvious "working position" indication, the operator can only use the method of counting the "number of circles" to judge the "working position" of the circuit breaker cabinet body. The disadvantage of this judgment method is that it relies too much on the skills of the staff and is prone to misjudgment and deviation. There have been cases where the circuit breaker failed to close because it was not fully sent to the "working position". For example, during a major overhaul of Unit 3 of a power station, the No. 3 main transformer will be shut down for maintenance, and it is necessary to switch the power supply of Unit 3 from the normal power supply to the backup power supply. During the operation of switching the 6kV normal three-section bus from the working power supply to the backup power supply, the backup power supply incoming circuit breaker of this section of the bus did not close as expected, resulting in the loss of power to the third column of the bus. The diesel engine automatically started and loaded in stages according to the power failure signal. The cause of the incident was that the operation of pushing the backup power supply incoming circuit breaker of the 6kV normal three-section bus into the "working position" was not fully in place, resulting in a closing failure.

[0004] Therefore, it is necessary to design a judgment device and a judgment method for judging the "working position" of a 6kV circuit breaker in a nuclear power plant to prevent the recurrence of the power transmission operation failure event. Summary of the invention

[0005] In view of the prior art, the present invention proposes a judgment device and a judgment method for judging the working position of a circuit breaker, which are used to solve the technical problem that the existing method of judging the working position of a 6kV circuit breaker cabinet body of a nuclear power plant by counting the number of "circles" is prone to misjudgment and deviation.

[0006] The technical solution of the present invention:

[0007] A judgment device for judging the working position of a circuit breaker comprises: a circuit breaker, a resistor, an instrument control module, a signal screen display module, an OR gate negation logic module, an alarm module, a cable and a power supply module; the circuit breaker is connected to the instrument control module via a cable, a resistor is connected in parallel between the circuit breaker and the instrument control module, one end of the instrument control module is connected to the OR gate negation logic module via a cable; a signal screen display is connected between the instrument control module and the OR gate negation logic module; the other end of the instrument control module is connected to the power supply module; the OR gate negation logic module is also connected to the alarm module.

[0008] A circuit breaker auxiliary circuit breaker contact is also arranged inside the circuit breaker; and a compression spring is also arranged on the circuit breaker auxiliary circuit breaker contact.

[0009] A method for determining the working position of a circuit breaker as described above comprises the following steps:

[0010] Step 1: Power on the 6kV circuit breaker trolley and move the circuit breaker from the "test position" to the "working position";

[0011] Step 2: The auxiliary circuit breaker contact closing signal is sent to the instrumentation and control module, and the circuit disconnection monitoring is performed;

[0012] Step 3: Determine whether the circuit breaker has been sent to the "working position";

[0013] Step 4: The circuit breaker is out of the status monitoring of the "working position".

[0014] The step 1 comprises: when the 6kV circuit breaker trolley is powered on, the operator shakes the operating handle clockwise, and the spring on the auxiliary circuit breaker contact of the circuit breaker is compressed, until the operator shakes the operating handle clockwise for 20 turns, the spring is fully compressed into place, and the auxiliary circuit breaker contact of the circuit breaker makes a clicking sound, and the elastic force of the compressed spring ensures that the auxiliary circuit breaker contact of the circuit breaker is closed and reliably contacted.

[0015] The step 2 includes: supplying power to the instrument and control module through the power module, sending the closing signal of the auxiliary circuit breaker contact of the circuit breaker in step 1 to the instrument and control module through the cable, and the resistor connected in parallel between the circuit breaker and the instrument and control module is used to reduce the voltage value before the closing signal of the auxiliary circuit breaker contact of the circuit breaker is sent to the instrument and control module, so as to monitor the circuit break.

[0016] The step three includes: the instrument control module collects the signal of the auxiliary circuit breaker contact 2 of the circuit breaker being closed, and when the set voltage value is met, the instrument control module sends a high level signal "1", then it is judged that the circuit breaker has been sent to the "working position", and the signal that triggers the circuit breaker 1 to the "working position" is sent to the signal screen display module in the main control room.

[0017] The step 4 includes: while judging whether the circuit breaker is sent to the "working position" in step 3, the high-level signal emitted by the instrument control module also passes through the OR gate and the NOT logic module for logical judgment to judge whether the circuit breaker is out of the "working position" and issue a status monitoring.

[0018] In the step 4, judging whether the circuit breaker is out of the "working position" and issuing a status monitoring specifically includes: when the circuit breaker is in the "working position", the signal output by the OR gate and the non-logic block is "0", and when the output signal of the OR gate and the non-logic block is "1", an alarm signal indicating that the circuit breaker is out of the "working position" is triggered and sent to the alarm module, thereby completing the status monitoring of the circuit breaker being out of the "working position".

[0019] Beneficial effects of the present invention:

[0020] (1) The present invention designs a judgment device and judgment method for judging the working position of a circuit breaker. The judgment device uses the auxiliary circuit breaker contacts of the circuit breaker as the core of the device on the basis of the original equipment, and uses the instrumentation module to realize the operation of the judgment device, which is low in cost. Moreover, the device can display the status of the corresponding equipment on the instrumentation screen of the main control room through the auxiliary circuit breaker contacts of the circuit breaker, realizing the display characteristics of the working position of the circuit breaker in a concise, intuitive and easy-to-identify manner.

[0021] (2) The present invention designs a judgment device for judging the working position of a circuit breaker and a judgment device in a judgment method. When designing the circuit, a resistor is added, which can distinguish the low-level signal generated when the circuit breaker leaves the working position from the disappearance of the high-level signal caused by the circuit itself being broken, and alarm, thereby realizing the function of precise monitoring; it makes up for the design deficiency that there is no clear indication when the 6kV circuit breaker is placed in the "working position" in the past.

[0022] (3)) The present invention designs a judgment device and a judgment method for judging the working position of a circuit breaker, which utilizes operating personnel to make accurate judgments, thereby improving the success rate of power transmission of the equipment; in addition, it also provides a state monitoring method for the backup power circuit breaker that is in a standby state for a long time, thereby improving the overall reliability of the backup power supply of the nuclear power plant; the judgment method can be implemented in the overhaul window, has strong operability, and the design concept conforms to the operating habits of the operating personnel and has a user-friendly interface.

[0023] (4) The present invention designs a judgment device and a judgment method for judging the working position of a circuit breaker, which adopts a circuit breaker auxiliary contact with high reliability, can truly reflect the state of the circuit breaker, and transmits signals through cables with high credibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1A circuit connection diagram of a judging device for judging the working position of a circuit breaker designed for the present invention;

[0025] Among them: 1-circuit breaker; 2-circuit breaker auxiliary circuit breaker contact; 3-resistance; 4-instrumentation and control module; 5-signal screen display module; 6-OR gate negation logic module; 7-alarm module; 8-cable; 9-power supply module. DETAILED DESCRIPTION

[0026] A device and method for determining a circuit breaker operating position according to the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0027] The present invention is designed to be used for judging the working position of a circuit breaker and its judgment method, comprising: a circuit breaker 1, a resistor 3, an instrumentation module 4, a signal screen display module 5, an OR gate negation logic module 6, an alarm module 7, a cable 8 and a power supply module 9; the circuit breaker 1 is connected to the instrumentation module 4 through the cable 8, the circuit breaker 1 and the instrumentation module 4 are further connected with the resistor 3 in parallel, one end of the instrumentation module 4 is further connected with the OR gate negation logic module 6 through the cable 8; the signal screen display module 5 is further connected between the instrumentation module 4 and the OR gate negation logic module 6; the other end of the instrumentation module 4 is connected with the power supply module 9; the OR gate negation logic module 6 is further connected with the alarm module 7. The circuit breaker 1 is further provided with a circuit breaker auxiliary circuit breaker contact 2; the circuit breaker auxiliary circuit breaker contact 2 is further provided with a compression spring.

[0028] The specific steps of the method for determining the working position of a 6kV circuit breaker in a nuclear power plant designed by the present invention include:

[0029] Step 1: The 6kV circuit breaker trolley is powered on, and the circuit breaker is moved from the "test position" to the "working position"; when the 6kV circuit breaker trolley is powered on, the operator shakes the operating handle clockwise, and the spring on the auxiliary circuit breaker contact 2 of the circuit breaker 1 is compressed. After the operator shakes the operating handle clockwise for 20 circles, the spring is fully compressed into place, and the auxiliary circuit breaker contact 2 of the circuit breaker makes a click sound. The elastic force of the compressed spring ensures that the auxiliary circuit breaker contact 2 of the circuit breaker is closed and in reliable contact.

[0030] Step 2: The closing signal of the auxiliary circuit breaker contact 2 of the circuit breaker is sent to the instrumentation and control module 4, and the circuit break monitoring is performed; the instrumentation and control module 4 is powered by the power module 9. In step 1, the closing signal of the auxiliary circuit breaker contact 2 of the circuit breaker is sent to the instrumentation and control module 4 through the cable 8. The resistor 3 connected in parallel between the circuit breaker 1 and the instrumentation and control module 4 is used to reduce the voltage value before the closing signal of the auxiliary circuit breaker contact 2 of the circuit breaker is sent to the instrumentation and control module 4, so as to monitor the circuit break.

[0031] Step 3: Determine whether the circuit breaker has been sent to the "working position"; the instrumentation and control module 4 collects the signal of the closing of the auxiliary circuit breaker contact 2 of the circuit breaker. When the set voltage value is met, the instrumentation and control module 4 sends a high-level signal "1", and it is determined that the circuit breaker has been sent to the "working position". The signal that triggers the circuit breaker 1 to the "working position" is sent to the signal screen display module 5 in the main control room.

[0032] Step 4: Status monitoring of the circuit breaker being out of the "working position"; while judging whether the circuit breaker is sent to the "working position" in step 3, the high-level signal emitted by the instrumentation and control module 4 also passes through the OR gate taking the NOT logic module 6 for logical judgment to judge whether the circuit breaker is out of the "working position" and issue a status monitoring. Judging whether the circuit breaker is out of the "working position" and issuing a status monitoring specifically includes: when the circuit breaker is in the "working position", the signal output by the OR gate taking the NOT logic block 6 is "0", and when the signal output by the OR gate taking the NOT logic block 6 is "1", the alarm signal of the circuit breaker being out of the "working position" is triggered and sent to the alarm module 7, completing the status monitoring of the circuit breaker being out of the "working position".

[0033] The present invention designs a judgment device and judgment method for judging whether a 6kV circuit breaker of a nuclear power plant is placed in a working position, which makes up for the design defect that the existing 6kV circuit breaker cannot clearly indicate when it is placed in the "working position", and improves the performance of the circuit breaker. At the same time, the device of the present invention can display the 6kV circuit breaker in the "working position" and out of the working position in the main control room very conspicuously, so that the operating personnel can accurately grasp the status of the 6kV circuit breaker. The present invention unifies the judgment method of whether the 6kV circuit breaker is in the working position, and at the same time adds the working position monitoring and alarm function of the 6kV circuit breaker, which provides a powerful guarantee means for the operating personnel to monitor whether the circuit breaker is in the working position.

[0034] The embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the field without departing from the purpose of the present invention.

Claims

1. A method for determining a circuit breaker working position by a determination device, characterized in that: The judging device for judging the working position of a circuit breaker comprises: a circuit breaker (1), a resistor (3), an instrumentation module (4), a signal screen display module (5), an OR gate negation logic module (6), an alarm module (7), a cable (8) and a power module (9); the circuit breaker (1) is connected to the instrumentation module (4) via the cable (8); a resistor (3) is further connected in parallel between the circuit breaker (1) and the instrumentation module (4); one end of the instrumentation module (4) is further connected to the OR gate negation logic module (6) via the cable (8); a signal screen display module (5) is further connected between the instrumentation module (4) and the OR gate negation logic module (6); the other end of the instrumentation module (4) is connected to the power module (9); the OR gate negation logic module (6) is further connected to the alarm module (7); The circuit breaker (1) is also provided with a circuit breaker auxiliary circuit breaker contact (2); the circuit breaker auxiliary circuit breaker contact (2) is also provided with a compression spring; the judging method of the judging device for judging the working position of the circuit breaker comprises the following steps: Step 1: Power on the 6kV circuit breaker trolley and move the circuit breaker from the "test position" to the "working position"; Step 2: The closing signal of the auxiliary circuit breaker contact (2) of the circuit breaker is sent to the instrumentation and control module (4), and the circuit disconnection monitoring is performed; Step 3: Determine whether the circuit breaker has been sent to the "working position"; Step 4: The circuit breaker is out of the "working position" status monitoring; The step 1 comprises: when the 6kV circuit breaker trolley is powered on, the operator shakes the operating handle clockwise, and the spring on the auxiliary circuit breaker contact (2) of the circuit breaker (1) is compressed, until the operator shakes the operating handle clockwise for 20 turns, the spring is fully compressed, and the auxiliary circuit breaker contact (2) of the circuit breaker makes a clicking sound, and the elastic force of the compressed spring ensures that the auxiliary circuit breaker contact (2) of the circuit breaker is closed and reliably in contact; The step 2 comprises: supplying power to the instrument control module (4) through the power module (9); the closing signal of the auxiliary circuit breaker contact (2) of the circuit breaker in step 1 is sent to the instrument control module (4) through the cable (8); the resistor (3) connected in parallel between the circuit breaker (1) and the instrument control module (4) is used to reduce the voltage value before the closing signal of the auxiliary circuit breaker contact (2) of the circuit breaker is sent to the instrument control module (4), so as to monitor the circuit disconnection; The step three comprises: the instrument control module (4) collects the signal of the closing of the auxiliary circuit breaker contact (2) of the circuit breaker, and when the set voltage value is met, the instrument control module (4) sends a high level signal "1", and it is judged that the circuit breaker has been sent to the "working position", and the signal of the circuit breaker (1) to the "working position" is sent to the signal screen display module (5) in the main control room; In step 4, judging whether the circuit breaker is out of the "working position" and issuing a status monitoring signal specifically comprises: when the circuit breaker is in the "working position", the signal output by the OR gate negation logic module (6) is "0", and when the signal output by the OR gate negation logic module (6) is "1", an alarm signal indicating that the circuit breaker is out of the "working position" is sent to the alarm module (7), thereby completing the status monitoring of the circuit breaker being out of the "working position".

2. A method for determining a circuit breaker working position according to claim 1, characterized in that: The step 4 comprises: while judging whether the circuit breaker is in the "working position" in step 3, the high-level signal emitted by the instrument control module (4) is also passed through the OR gate negation logic module (6) to perform logic judgment, to judge whether the circuit breaker is out of the "working position" and to issue a status monitoring.

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