Opening and closing operation device of field suppression switch of synchronous phase modifier

Abstract

The invention discloses an opening and closing operation device for a field suppression switch of a synchronous phase modifier. The opening and closing operation device comprises an opening and closing operation loop, a locking loop and a field suppression switch control loop, the opening and closing operation loop is used for realizing closing operation and opening operation through a relay; the locking loop is used for realizing mutual locking of the opening and closing operation loops through an intermediate relay; and the field suppression switch control loop is used for realizing control operation on the field suppression switch. Control achieved through a control panel in the prior art is replaced with the opening and closing operation loop and the locking loop, a low-voltage control panel is not adopted, the reliability and stability of the operation loop are improved, misoperation caused by external electromagnetic interference and other factors is effectively avoided, the operation safety of the synchronous phase modifier is enhanced, and the service life of the synchronous phase modifier is prolonged. Stable work under various working conditions is ensured, and the phase modifier tripping problem caused by operation loop faults is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of power equipment, and more specifically, relates to a closing and opening operation device for a synchronous condenser field discharge switch. Background Art

[0002] In modern power systems, synchronous condensers play an important role. The stability of the closing and opening operation circuit of the field discharge switchgear of the synchronous condenser is directly related to the safe and reliable operation of the synchronous condenser and even the entire power system. However, in recent years, problems have frequently occurred in the closing and opening circuits of the field discharge switch of the synchronous condenser. Among them, the tripping events of the synchronous condenser caused by the operation circuit account for a relatively high proportion. The original operation circuit uses a 24V low-voltage circuit board for control. This design makes the circuit extremely sensitive to the electromagnetic environment during operation and is extremely vulnerable to the electromagnetic interference between the electronic devices of the excitation system of the synchronous condenser.

[0003] In related technologies, there has been a situation where the synchronous condenser unit tripped out of operation due to the sudden opening of the field discharge switch, which had a serious impact on the stable operation of the power system. After the accident, it was necessary to replace the field discharge switch on-site and return the original field discharge switch to the factory for disassembly, inspection, and analysis. Finally, it was determined that the cause of the failure was that the low-voltage control circuit for opening the original GE field discharge switch was affected by external electromagnetic interference, resulting in an automatic opening phenomenon. Such incidents fully expose the serious defects in the design of the original operation circuit and its inability to meet the actual operation requirements in terms of electromagnetic compatibility.

[0004] Therefore, how to improve the anti-electromagnetic interference ability of the closing and opening operation circuit of the synchronous condenser field discharge switchgear, enhance the reliability of the operation circuit, ensure the stable operation of the synchronous condenser under various working conditions, and avoid problems such as tripping of the synchronous condenser caused by operation circuit failures is a key issue of concern to those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a closing and opening operation device for a synchronous condenser field discharge switch, which improves the anti-electromagnetic interference ability of the closing and opening operation circuit of the synchronous condenser field discharge switchgear, enhances the reliability of the operation circuit, ensures the stable operation of the synchronous condenser under various working conditions, and avoids the problem of tripping of the synchronous condenser caused by operation circuit failures.

[0006] In view of the above-mentioned defects or improvement requirements in the prior art, the present invention provides a closing and opening operation device for a synchronous condenser field discharge switch, including: a closing and opening operation circuit, a locking circuit, and a field discharge switch control circuit;

[0007] The closing and opening operation circuit is used to achieve closing operation and opening operation through a relay;

[0008] The locking circuit is used to achieve mutual locking of the closing and opening operation circuits through an intermediate relay;

[0009] The field discharge switch control circuit is used to control the field discharge switch.

[0010] Optionally, the closing and opening operation circuit includes: one closing operation circuit and two independent opening operation circuits.

[0011] Optionally, the closing operation circuit includes: a high-power closing relay ZJ1, a high-power DC contactor 61HC, a time relay SJ1, a freewheeling diode, a pulse blocking relay FMJ1 / FMJ2, an input node of an external protection device, and an auxiliary contact of the switch body.

[0012] Optionally, the closing and opening interlock circuit includes: an opening interlock circuit and a closing interlock circuit

[0013] Optionally, the closing interlock function of the opening interlock circuit and the opening interlock function of the closing interlock circuit are realized by an intermediate relay.

[0014] Optionally, the field discharge switch control circuit includes: a field discharge switch closing control circuit and a field discharge switch opening control circuit.

[0015] Optionally, the power supply of the field discharge switch closing control circuit is connected in parallel with a varistor V1, a capacitor C1, and a bridge rectifier circuit BRL1, and the bridge rectifier circuit BRL1 is connected to the closing coil circuit.

[0016] Optionally, the field discharge switch opening control circuit includes: a high-power opening coil, a diode, and a freewheeling resistor.

[0017] A closing and opening operation device for a field discharge switch of a synchronous condenser provided by the present application includes: a closing and opening operation circuit, an interlock circuit, and a field discharge switch control circuit; the closing and opening operation circuit is used to perform closing and opening operations through a relay; the interlock circuit is used to mutually interlock the closing and opening operation circuits through an intermediate relay; the field discharge switch control circuit is used to control the field discharge switch.

[0018] It has the following beneficial effects:

[0019] Through the closing and opening operation circuit and the interlock circuit, the control implemented by the control board in the prior art is replaced, rather than using a low-voltage control board, which improves the reliability and stability of the operation circuit, effectively avoids misoperations caused by external electromagnetic interference and other factors, enhances the safety of the synchronous condenser operation, ensures its stable operation under various working conditions, and reduces problems such as the tripping of the synchronous condenser caused by operation circuit failures. Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on the provided accompanying drawings.

[0021] Figure 1 Schematic diagram of a closing and opening operation device for a synchronous condenser field discharge switch provided by an embodiment of the present application;

[0022] Figure 2 Schematic diagram of a closing operation circuit provided by an embodiment of the present application;

[0023] Figure 3 Schematic diagram of an opening operation circuit provided by an embodiment of the present application;

[0024] Figure 4 Schematic diagram of a closing control circuit for a field discharge switch provided by an embodiment of the present application;

[0025] Figure 5 Schematic diagram of an opening control circuit for a field discharge switch provided by an embodiment of the present application. Detailed implementation manners

[0026] The object of the present application is to provide a closing and opening operation device for a synchronous condenser field discharge switch, improve the anti-electromagnetic interference ability of the closing and opening operation circuits of the synchronous condenser field discharge switch cabinet, enhance the reliability of the operation circuits, ensure the stable operation of the synchronous condenser under various working conditions, and avoid the problem of the synchronous condenser tripping caused by operation circuit failures.

[0027] In order to make the object, technical solutions and advantages of the present invention clearer, the following will further describe the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] The following will illustrate a closing and opening operation device for a synchronous condenser field discharge switch provided by the present application through an embodiment.

[0029] Please refer to Figure 1 , Figure 1 Schematic diagram of a closing and opening operation device for a synchronous condenser field discharge switch provided by an embodiment of the present application.

[0030] In this embodiment, the device may include:

[0031] Closing and opening operation circuit 10, interlocking circuit 20, exciter switch control circuit 30;

[0032] The closing and opening operation circuit 10 is used to realize the closing operation and opening operation through relays; the interlocking circuit 20 is used to realize the mutual interlocking of the closing and opening operation circuits through intermediate relays; the exciter switch control circuit 30 is used to realize the control operation of the exciter switch.

[0033] Among them, the closing and opening operation device of the synchronous condenser exciter switch realizes the precise control of the closing and opening operation of the exciter switch, the reliable interlocking between circuits, and the effective control of the exciter switch through the coordinated work of each part of the circuit. Each circuit cooperates with each other to ensure that the exciter switch can accurately act under different working conditions, and guarantee the safe and stable operation of the synchronous condenser and the power system.

[0034] The closing and opening operation device is composed of a closing and opening operation circuit, an interlocking circuit, and an exciter switch control circuit. The closing and opening operation circuit uses relays to realize the closing and opening operations; the interlocking circuit uses intermediate relays to achieve the mutual interlocking of the closing and opening operation circuits; the exciter switch control circuit realizes the control operation of the exciter switch.

[0035] Among them, the closing and opening operation circuit controls the conduction and disconnection of the circuit based on the on-off characteristics of the relay, so as to realize the closing and opening operations of the exciter switch. The relay can accurately switch the circuit state according to the control signal, make the current flow or be cut off along the predetermined path, and then drive the operating mechanism of the exciter switch to complete the closing and opening actions.

[0036] It includes one closing operation circuit and two independent opening operation circuits. In the closing operation circuit, there are high-power closing relay ZJ1, high-power DC contactor 61HC, time relay SJ1, freewheeling diode, pulse blocking relay FMJ1 / FMJ2, external protection device input node, auxiliary contact of the switch body and other components. The opening operation circuit is realized by connecting high-power opening coils in parallel with diodes (including freewheeling resistors).

[0037] Among them, the design of one closing and two independent openings provides multiple operation options, increasing the flexibility and reliability of the operation. The independent opening circuits can independently control the opening actions under different conditions, improving the fault handling ability; the multiple relays and components in the closing circuit cooperate with each other to ensure the accuracy and stability of the closing operation.

[0038] The interlocking circuit uses the contact logic control of the intermediate relay to prevent the closing and opening operations from being carried out simultaneously or at inappropriate times, ensuring the sequentiality and correctness of the operations. Through the electrical isolation and logic control functions of the intermediate relay, the interlock between the closing and opening operation circuits is realized, avoiding equipment damage or faults caused by misoperations.

[0039] Among them, it includes a trip locking circuit and a closing locking circuit. The locking closing function of the trip locking circuit and the locking trip function of the closing locking circuit are both realized by intermediate relays.

[0040] It can be seen that this locking circuit effectively prevents the tripping and closing conflicts caused by misoperation and improves the safety of operation. For example, during the closing process, the locking circuit can prevent the mis-triggering of the trip operation and ensure the smooth completion of the closing action; conversely, during the tripping, it can also avoid the interference of the closing operation and guarantee the safety of equipment and personnel.

[0041] The field discharge switch control circuit realizes the precise action of the field discharge switch by controlling the internal electromagnetic drive circuit and the high-power trip coil of the field discharge switch. According to the control signal, it drives the electromagnetic drive circuit to make the high-power trip coil generate sufficient magnetic force or electric power, pushing the contacts of the field discharge switch to perform opening and closing actions, thereby controlling the on-off state of the circuit.

[0042] Among them, it includes a closing control circuit of the field discharge switch and a tripping control circuit of the field discharge switch. The power supply of the closing control circuit is connected in parallel with a varistor V1, a capacitor C1, and a bridge rectifier circuit BRL1, and the bridge rectifier circuit BRL1 is connected to the closing coil circuit; the tripping control circuit includes a high-power trip coil, a diode, and a current-limiting resistor.

[0043] Among them, the varistor V1 can protect the circuit from high-voltage impact, the capacitor C1 filters high-frequency signals and smooths the voltage, and the bridge rectifier circuit BRL1 enhances the power supply applicability. These components together ensure the stable power supply and reliable operation of the closing control circuit. The high-power trip coil in the tripping control circuit provides a strong tripping force, and the diode and current-limiting resistor ensure the safety and stability of the tripping process, overall improving the accuracy and reliability of the field discharge switch control.

[0044] In this optional solution, through the closing and tripping operation circuits, the locking circuit replaces the control implemented by the control board in the prior art, rather than using a low-voltage control board, improving the reliability and stability of the operation circuit, effectively avoiding misoperation caused by external electromagnetic interference and other factors, enhancing the safety of the synchronous condenser operation, ensuring its stable operation under various working conditions, and reducing problems such as the tripping of the synchronous condenser caused by operation circuit failures.

[0045] Optionally, the closing and tripping operation circuit includes: one closing operation circuit and two independent tripping operation circuits.

[0046] In this optional solution, the further limitation of the closing and tripping operation circuit clarifies its structural design including one closing operation circuit and two independent tripping operation circuits. This design is based on the consideration of different operating conditions and control requirements of the synchronous condenser, and realizes more flexible and reliable closing and tripping operations through multi-circuit configuration.

[0047] In actual circuit design, a closing operation loop and two independent opening operation loops are constructed respectively. The closing operation loop connects components such as a high-power closing relay ZJ1, a high-power DC contactor 61HC, a time relay SJ1, a freewheeling diode, a pulse blocking relay FMJ1 / FMJ2, an input node of an external protection device, and an auxiliary contact of the switch body according to a specific electrical connection method to form a complete closing control path. The two opening operation loops are constructed independently by connecting high-power opening coils in parallel with diodes (including freewheeling resistors) to ensure that each opening loop can work independently and reliably.

[0048] In this alternative solution, the flexibility and reliability of the operation are increased. In different operating states, such as normal shutdown, emergency shutdown, or fault handling, different opening loops can be selected for operation according to needs, improving the ability to respond to emergencies. At the same time, the independent opening loops can reduce the risk of the entire closing and opening operation failing due to a single loop failure, ensuring the safe and stable operation of the synchronous condenser.

[0049] Please refer to Figure 2 , Figure 2 which is a schematic diagram of a closing operation loop provided by an embodiment of the present application.

[0050] Please refer to Figure 3 , Figure 3 which is a schematic diagram of an opening operation loop provided by an embodiment of the present application.

[0051] Optionally, the closing operation loop includes: a high-power closing relay ZJ1, a high-power DC contactor 61HC, a time relay SJ1, a freewheeling diode, a pulse blocking relay FMJ1 / FMJ2, an input node of an external protection device, and an auxiliary contact of the switch body.

[0052] Among them, the closing operation loop includes components such as a high-power closing relay ZJ1 and a high-power DC contactor 61HC that work together to control the on / off of the circuit according to a control signal, realize the power supply or power-off of the closing coil, and thus drive the field discharge switch to close. The freewheeling diode is used to provide a current path when the relay coil is powered off to protect the relay contacts; the pulse blocking relay FMJ1 / FMJ2, the input node of the external protection device, the auxiliary contact of the switch body, etc. participate in the control logic to ensure the accuracy and safety of the closing operation.

[0053] In terms of circuit connection, components such as high-power closing relay ZJ1, high-power DC contactor 61HC, and time relay SJ1 are connected in a loop between the power supply and the closing coil according to a certain sequence and logic. The freewheeling diode is connected in parallel with the relay coil. When the relay coil is de-energized, it provides a freewheeling path for the current in the coil to prevent the generation of excessive induced electromotive force from damaging the relay contacts. The pulse blocking relays FMJ1 / FMJ2 control the conduction or cut-off of the circuit according to external control signals or the instructions of the protection device. The external protection device input node receives external protection signals, and the auxiliary contacts of the switch body feedback the switch status information, jointly participating in the control logic of the closing operation.

[0054] Among them, the collaborative action of multiple components improves the reliability and accuracy of the closing operation. High-power components can provide sufficient driving ability to ensure the smooth progress of the closing action; the time relay SJ1 can achieve delay control of the closing operation to meet specific operation timing requirements; the freewheeling diode protects the relay contacts and extends the service life of the relay; the participation of the pulse blocking relays FMJ1 / FMJ2, the external protection device input node, and the auxiliary contacts of the switch body enables the closing operation to be accurately controlled according to the system status and external instructions, enhancing the safety and stability of the system.

[0055] Optionally, the closing and tripping interlock circuit includes: a tripping interlock circuit and a closing interlock circuit

[0056] This optional solution refines the structure of the closing and tripping interlock circuit, dividing it into a tripping interlock circuit and a closing interlock circuit. This division is to respectively achieve the interlock of the tripping operation on the closing operation and the interlock of the closing operation on the tripping operation. Through the mutually restrictive logical relationship, it prevents incorrect operations at inappropriate times and ensures the safety and sequence of the field discharge switch operation.

[0057] In circuit design, the specific circuit connections of the tripping interlock circuit and the closing interlock circuit are respectively constructed. By reasonably selecting and connecting electrical components such as relays and contactors, the interlock function is achieved using the logical relationship of their contacts. For example, in the tripping interlock circuit, when a tripping operation occurs, the power supply or control signal of the closing circuit is cut off through the action of the corresponding relay contacts, making the closing operation impossible; similarly, in the closing interlock circuit, the tripping operation is also prevented from being accidentally triggered during the closing operation.

[0058] In this alternative solution, the closing and opening conflicts caused by misoperations are effectively prevented, improving the safety of operations. For example, during the operation of the equipment, if the opening operation signal is accidentally triggered due to false signals or faults, the opening interlock circuit will prevent the closing operation from proceeding simultaneously, avoiding equipment damage or power system failures that may be caused by chaotic switch states. Similarly, the closing interlock circuit can also prevent accidental opening during the closing process, ensuring the sequentiality and correctness of operations and safeguarding the safety of equipment and personnel.

[0059] Optionally, the closing blocking function of the opening interlock circuit and the opening blocking function of the closing interlock circuit are implemented through intermediate relays.

[0060] In this alternative solution, it is clear that the implementation method of the blocking function in the opening and closing interlock circuits is accomplished through intermediate relays. Intermediate relays play the roles of electrical isolation and signal conversion in the circuit. Their contacts act according to the logical relationship of the control signals, thereby realizing the blocking of the closing operation by the opening interlock circuit and the blocking of the opening operation by the closing interlock circuit. Intermediate relays can amplify, convert, and isolate control signals, ensuring the reliable implementation of the blocking function without being interfered by other circuits.

[0061] Among them, intermediate relays are respectively connected to the opening interlock circuit and the closing interlock circuit. When an opening operation occurs, the control signal in the opening circuit causes the intermediate relay to act, and its contacts change state, cutting off the key connection points in the closing circuit, such as the power supply circuit or the control signal circuit, thereby realizing the closing blocking function; similarly, when a closing operation occurs, the control signal of the closing circuit drives the corresponding intermediate relay, causing its contacts to disconnect the relevant connections in the opening circuit, realizing the opening blocking function. The selection and parameter setting of the intermediate relay should be determined according to the requirements of the actual circuit voltage, current, control logic, etc., to ensure its normal operation and reliable blocking performance.

[0062] It can be seen that this alternative solution realizes the blocking function through intermediate relays, improving the reliability and stability of the blocking. The electrical isolation characteristic of the intermediate relay can avoid electrical interference between the opening and closing operation circuits, preventing blocking failure caused by interference. The large capacity and high reliability of its contacts can adapt to complex industrial environments and frequent operation requirements, effectively preventing opening and closing conflicts caused by misoperations or faults, safeguarding the safe operation of equipment, and reducing equipment damage and shutdown accidents caused by operation errors.

[0063] Optionally, the field discharge switch control circuit includes: a field discharge switch closing control circuit and a field discharge switch opening control circuit.

[0064] This alternative solution subdivides the field discharge switch control circuit into a field discharge switch closing control circuit and a field discharge switch opening control circuit. These two circuits are responsible for controlling the closing and opening actions of the field discharge switch respectively. Through different circuit designs and component configurations, precise and reliable control of the field discharge switch is achieved. The closing control circuit provides the required energy and control signals for the field discharge switch to close its contacts; the opening control circuit separates the contacts of the field discharge switch when needed to disconnect the circuit and ensure the safety of the equipment.

[0065] Among them, the field discharge switch closing control circuit is connected in parallel with a varistor V1, a capacitor C1, and a bridge rectifier circuit BRL1 through a specific power supply connection method, and the bridge rectifier circuit BRL1 is connected to the closing coil circuit. The varistor V1 is used for overvoltage protection, the capacitor C1 filters high-frequency signals and smooths the voltage, and the bridge rectifier circuit BRL1 converts the AC power supply into a DC power supply (when using AC power supply) or processes the DC power supply to provide a stable DC power supply for the closing coil. The field discharge switch opening control circuit mainly consists of a high-power opening coil, a diode, and a current-limiting resistor. The high-power opening coil generates a strong magnetic force under the action of the opening signal to separate the switch contacts, and the diode and the current-limiting resistor are used to protect the opening coil and control the current change during the opening process.

[0066] The two independent control circuits in this alternative solution are optimized for closing and opening operations respectively, improving the accuracy and reliability of control. The component combination in the closing control circuit ensures a stable and appropriate power supply during the closing operation, avoiding closing failure caused by power fluctuations or interference. The high-power opening coil in the opening control circuit provides sufficient opening force, and the diode and the current-limiting resistor ensure the safety and smoothness of the opening process, reducing problems such as arcs and overvoltages during opening, thereby extending the service life of the equipment and improving the performance and reliability of the entire field discharge switch control circuit.

[0067] Please refer to Figure 4 , Figure 4 which is a schematic diagram of a field discharge switch closing control circuit provided by an embodiment of this application.

[0068] Optionally, the power supply of the field discharge switch closing control circuit is connected in parallel with a varistor V1, a capacitor C1, and a bridge rectifier circuit BRL1, and the bridge rectifier circuit BRL1 is connected to the closing coil circuit.

[0069] This alternative solution further elaborates on the design principle of the power supply part of the closing control circuit of the field discharge switch. The parallel varistor V1 is used to protect the circuit from the impact of instantaneous overvoltage and prevent high voltage from damaging the components in the circuit; the capacitor C1 filters out high-frequency noise signals in the power supply, making the power supply output smoother and more stable. At the same time, it can also prevent high-frequency signals from interfering with the electromagnetic drive unit Q1 and affecting its normal operation; the bridge rectifier circuit BRL1 realizes the rectification function of the AC power supply (when AC power supply is used), converts it into a DC power supply, or performs necessary processing on the DC power supply to meet the requirements of the closing coil circuit for the power supply and ensure the reliable operation of the closing operation.

[0070] Specifically, in terms of circuit connection, the varistor V1 and the capacitor C1 are connected in parallel with the power supply. The characteristics of the varistor V1 cause it to conduct rapidly when the voltage exceeds a certain threshold, shunting the overvoltage and protecting the subsequent circuit components. The capacitor C1 is connected in parallel with the power supply and uses its capacitance characteristics to bypass high-frequency signals, making the power supply entering the bridge rectifier circuit BRL1 and the closing coil circuit purer. The input end of the bridge rectifier circuit BRL1 is connected to the power supply, and the output end is connected to the closing coil circuit, providing the processed power supply to the closing coil to drive its operation.

[0071] Among them, the existence of the varistor V1 improves the overvoltage resistance of the circuit, effectively protects the circuit components from overvoltage damage caused by factors such as power grid fluctuations and lightning strikes, and reduces the equipment failure rate. The filtering effect of the capacitor C1 ensures the stability and smoothness of the power supply, reduces the interference of power supply noise on the electromagnetic drive unit Q1, improves the accuracy and reliability of electromagnetic drive, and helps the precise control of the closing operation. The bridge rectifier circuit BRL1 enhances the versatility of the power supply. Whether it is an AC power supply or a DC power supply, it can provide a suitable power supply for the closing coil after appropriate processing, improves the adaptability of the equipment to different power supply environments, and ensures the reliable execution of the closing operation under various working conditions.

[0072] Please refer to Figure 5 , Figure 5 which is a schematic diagram of a field discharge switch opening control circuit provided by an embodiment of the present application.

[0073] Optionally, the field discharge switch opening control circuit includes: a high-power opening coil, a diode, and a current-limiting resistor.

[0074] This alternative solution details the components and operating principles of the shunt trip control circuit of the field discharge switch. The high-power shunt trip coil is the key actuating component for implementing the shunt trip operation. When a shunt trip signal is applied to the coil, a current passes through the coil, generating a strong magnetic force that drives the contacts of the field discharge switch to quickly separate, thereby cutting off the circuit. The diode is connected in parallel with the shunt trip coil. At the moment when the shunt trip coil is de-energized, it provides a freewheeling path for the current in the coil, avoiding damage to the coil or other components due to excessive induced electromotive force caused by sudden current changes. The freewheeling resistor is used to limit the magnitude of the freewheeling current, further protecting the circuit and controlling the current change during the shunt trip process, making the shunt trip operation more stable and reliable.

[0075] Among them, the high-power shunt trip coil is connected in parallel with the diode and the freewheeling resistor in the shunt trip control circuit. When the shunt trip control signal arrives, the power supply supplies power to the shunt trip coil, causing the coil to generate a magnetic force to drive the switch contacts to trip. After the shunt trip operation is completed, the coil is de-energized. At this time, the diode conducts, providing a freewheeling path for the current in the coil. The freewheeling resistor and the diode work together to control the magnitude and decay process of the freewheeling current. The parameters of the diode and the freewheeling resistor should be reasonably selected according to the inductance, operating voltage, current and other parameters of the shunt trip coil to ensure effective protection of the coil and achieve a smooth current transition during the shunt trip process.

[0076] This alternative solution provides sufficient shunt trip power for the high-power shunt trip coil, ensuring that the shunt trip operation of the field discharge switch can be quickly and reliably achieved under various working conditions, effectively protecting the safety of equipment and the power system. The combined use of the diode and the freewheeling resistor avoids the generation of excessive induced electromotive force in the shunt trip coil at the moment of power-off, prevents insulation damage of the coil and overvoltage breakdown of other components, and extends the service life of the equipment. At the same time, the control of the freewheeling current by the freewheeling resistor makes the shunt trip process more stable, reduces the generation of arcs and electromagnetic interference during shunt trip, improves the reliability and stability of the shunt trip operation, and helps to maintain the stable operation of the power system.

[0077] The following further illustrates a shunt and closing operation device for a synchronous condenser field discharge switch provided by the present application through another specific embodiment.

[0078] In this embodiment, the device includes a shunt and closing operation circuit of the field discharge switch, a shunt and closing interlock circuit, and a control circuit for the field discharge switch body part. The operation circuit includes one closing operation circuit and two independent shunt trip operation circuits.

[0079] Among them, as Figure 2 、 Figure 3As shown in the figure, the on-off control circuit of the synchronous condenser field discharge switchgear outside includes: a high-power closing relay ZJ1, a high-power DC contactor 61HC, a time relay SJ1, a freewheeling diode, a pulse blocking relay FMJ1 / FMJ2, and also includes various electronic devices such as the closing coil HQ and the tripping coil TQ1 of the field discharge switch body. In addition, the on-off circuit also includes the input node of the external protection device and the auxiliary contact of the switch body.

[0080] Among them, as Figure 4 shown, the main body part of the closing operation circuit of the field discharge switch is powered by the AC (DC) power supply for the circuit. A varistor V1 is connected in parallel at the power supply inlet, which is used for overvoltage protection and surge current suppression in this electronic circuit. An inlet capacitor C1 is connected in parallel at the power supply inlet, which is used to filter out excess high-frequency signals, prevent interference to the electromagnetic drive unit Q1, and also has the function of smoothing the voltage. After the circuit, it passes through a bridge rectifier circuit BRL1, which can be powered by AC or DC power supply to enhance its versatility. The load of BRL1 includes a diode D, a series RC circuit and Q1, which can achieve the adjustment of the circuit response speed, and Q1 is realized by the parallel diode D and the closing coil. This diode D can provide freewheeling for it.

[0081] Among them, as shown in the appendix Figure 5 shown, the main body part of the opening operation circuit of the field discharge switch also realizes the opening control of the field discharge switch by the method of connecting a high-power opening coil in parallel with a diode (including a freewheeling resistor).

[0082] Among them, the on-off control circuit of the synchronous condenser field discharge switchgear can adapt to AC and DC power supplies with strong power supply such as 220V or 110V, can meet the requirements of different occasions, and the power supply of the first-way opening and closing operation circuits can be shared or independently powered, and the power supply of the second-way opening circuit is independent of the power supply of the first-way opening circuit.

[0083] Among them, as Figure 2 、 Figure 3 shown, its characteristic is that the realization of the opening operation circuit blocking closing function and the closing operation circuit blocking opening function depends on the intermediate relay ZJ21.

[0084] Among them, based on the external operation circuit and the blocking circuit, plus the internal electromagnetic drive circuit and the high-power opening coil of the switch body, the opening and closing control of the switch body is realized.

[0085] Furthermore, according to the actual parameters of the components in the shunt and series operation circuits of the field discharge switch used in the actual site, an electromagnetic transient simulation model of the shunt and series operation circuits of the field discharge switch was established in MATLAB / SIMULINK. Among them, high-power closing relay ZJ1, high-power opening relays ZJ2-3, high-power contactor 61HC, time relays SJ1-3, etc. belong to the energized coil components, and their electromagnetic characteristics can be simulated by the series connection of an inductor and a resistor. To avoid the instantaneous high voltage generated when the circuit is disconnected from damaging the contacts of the relay, a freewheeling diode and a freewheeling resistor can be connected in parallel across the coil. The auxiliary contacts of the relay / contactor are controlled by voltage to conduct / turn off the node, and the transition time of conduction or turn-off is simulated by setting a time delay. When the voltage across the coil is greater than the threshold voltage Vk, the auxiliary contact conducts or turns off; otherwise, the auxiliary contact does not operate. The freewheeling box consists of a freewheeling diode and a resistor. The main parameters of the freewheeling diode include the threshold voltage, conduction time, and equivalent resistance during conduction and turn-off. Usually, the large and small resistance model is used for simulation, and the LC model is considered when using the dynamic model.

[0086] The embodiments in the specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and reference can be made to the description in the method part for the relevant parts.

[0087] Those skilled in the art can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0088] The steps of the method or algorithm described in combination with the embodiments disclosed herein can be directly implemented by hardware, a software module executed by a processor, or a combination of the two. The software module can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0089] The above has introduced in detail a closing and opening operation device for the field discharge switch of a synchronous condenser. Specific examples are used in this article to elaborate on the principle and implementation manner of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application. It should be noted that for those of ordinary skill in the art, without departing from the principle of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A synchronous phase condenser demagnetization switch opening and closing operation device, characterized in that: include: Opening and closing operation circuit, locking circuit, demagnetization switch control circuit; The closing and opening operation circuit is used to realize closing and opening operations through a relay; The locking circuit is used to realize the mutual locking of the opening and closing operation circuits through the intermediate relay; The demagnetization switch control circuit is used to control the demagnetization switch.

2. The opening and closing operating device according to claim 1, characterized in that: The opening and closing operation circuit comprises: one closing operation circuit and two independent opening operation circuits.

3. The opening and closing operating device according to claim 2, characterized in that: The closing operation circuit includes: a high-power closing relay ZJ1, a high-power DC contactor 61HC, a time relay SJ1, a freewheeling diode, a pulse-sealing relay FMJ1 / FMJ2, an external protection device input node, and auxiliary contacts of the switch body.

4. The opening and closing operating device according to claim 3, characterized in that: The opening and closing locking circuit comprises: an opening locking circuit and a closing locking circuit.

5. The opening and closing operating device according to claim 4, characterized in that: The locking closing function of the opening locking circuit and the locking opening function of the closing locking circuit are realized through an intermediate relay.

6. The opening and closing operating device according to claim 5, characterized in that: The demagnetization switch control circuit comprises: a demagnetization switch closing control circuit and a demagnetization switch opening control circuit.

7. The opening and closing operating device according to claim 6, characterized in that: The power supply of the demagnetization switch closing control circuit is connected in parallel with a varistor V1, a capacitor C1, and a bridge rectifier circuit BRL1, and the bridge rectifier circuit BRL1 is connected to the closing coil circuit.

8. The opening and closing operating device according to claim 7, characterized in that: The demagnetization switch opening control circuit comprises: a high-power opening coil, a diode, and a freewheeling resistor.

Images