CN215526408U - Multifunctional thyristor switching switch detection device - Google Patents
Multifunctional thyristor switching switch detection device Download PDFInfo
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- CN215526408U CN215526408U CN202121753852.XU CN202121753852U CN215526408U CN 215526408 U CN215526408 U CN 215526408U CN 202121753852 U CN202121753852 U CN 202121753852U CN 215526408 U CN215526408 U CN 215526408U
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Abstract
The utility model discloses a multifunctional thyristor fling-cut switch detection device, which is used for detecting a fling-cut switch of a thyristor and comprises a three-phase electric voltage regulator and a controller, wherein the three-phase electric voltage regulator is electrically connected with the controller, the first path of the output end of the three-phase electric voltage regulator is electrically connected with a static var generator through a first current transformer, and the first path of the output end of the three-phase electric voltage regulator is electrically connected with the thyristor to be detected through the first current transformer. According to the multifunctional thyristor switching switch detection device disclosed by the utility model, the controller adopts ARM + FPGA dual CPU processors to synchronize switching on-off response time Ton and the like of the thyristor switching device to be detected in a high-speed real-time manner, so that the use frequency of a traditional oscilloscope, an electric energy quality analyzer and a temperature recorder is reduced, the working efficiency is greatly improved, and the investment of special detection equipment is saved.
Description
Technical Field
The utility model belongs to the technical field of thyristor fling-cut switch detection, and particularly relates to a multifunctional thyristor fling-cut switch detection device.
Background
With the development of economy and the improvement of living standard of people, various industries put forward higher requirements on the reliability and quality of a power grid. Industrial enterprises are main users of electric energy, the electricity saving of the industrial enterprises plays a crucial role in saving energy, and the reactive power compensation is the most important measure for saving electric energy. The power factor of the user is high or low, and the power generation and power supply system plays a vital role in fully utilizing power generation and power supply, saving electric energy, improving voltage quality and even improving the economic benefit of enterprises. In today's power systems, the primary loads are generally inductive and the power factor is generally relatively low. The inductive load not only absorbs a certain active power from the power grid, but also absorbs a certain reactive power, so that the voltage of the power grid is reduced to a certain extent, and the electric energy is wasted to a certain extent. Reactive compensation is carried out through switching control of the capacitor bank, so that power factor can be improved to some extent, and the quality of the voltage of the power grid is improved. At present, certain surge and impact exist in the conventional mode of mechanically switching the capacitor at home and abroad, equipment is damaged, and the development requirement of social progress science and technology cannot be met to a great extent. Therefore, the mode of switching the capacitor based on the reactive compensation thyristor realizes no surge and no impact at the moment of switching. The reactive compensation is to maintain energy required by magnetic field and electric field oscillation between inductance and capacitance of power supply and electric equipment, and to ensure that reactive compensation switching capacitor devices can be divided into circuit breaker (contactor) switching capacitor devices and thyristor switching capacitor devices according to different control switches. The switching capacitor device of the circuit breaker (contactor) has the advantages of simple structure, convenient control, stable performance and low cost, but has the defect that when the circuit breaker is switched on, a switching filter branch circuit has a transient process which can generate over current and over voltage to influence the reliable operation of the capacitor and the series reactor; when the filtering branch circuit is cut off, the recovery voltage on the contact is higher, the possibility of switch reignition exists, and when the switch is repeatedly broken down for many times, high overvoltage is generated on the capacitor, so that equipment is damaged. Compared with a mechanical switch-switched capacitor, the thyristor switch of the thyristor-switched capacitor device has no contact point, the operation life of the thyristor-switched capacitor device is almost unlimited, the switching time of the thyristor can be accurately controlled, the capacitor can be quickly switched into a power grid without impact, the operation difficulty and impact current during switching are greatly reduced, the dynamic response time of the thyristor-switched capacitor device is about 0.01-0.02 s, the TSC can quickly track the sudden change of impact load, the optimal feed power factor is kept at any time, dynamic reactive compensation is realized, the reactive compensation quantity can quickly follow the change of actual demand quantity, the voltage fluctuation is reduced, the electric energy quality is improved, and the electric energy is saved. And the thyristor switched capacitor device has the advantages of no mechanical wear, high response speed, smooth switching, good comprehensive compensation effect and the like. The thyristor switched capacitor device is required to meet the standard requirements of GB/T29312-2012 'Low-voltage reactive power compensation switching device'.
The existing test of the type GB/T29312-2012 low-voltage reactive power compensation switching device of the thyristor switched capacitor switch product requires test items such as the working voltage range, the open-phase protection function, the surge current limit, the switching response time, the switching function, the electric service life, the temperature rise and the like of the thyristor.
At present, no thyristor switch detection device for switching a special capacitor is available in the market, and when a type test is carried out on a thyristor switching switch according to a GB/T29312-2012 type test project, a 12V thyristor trigger electrical signal and a current clamp are mostly converted into a 0-5V electrical signal to be connected to an oscilloscope or a data acquisition instrument to detect the switching response time Ton, Toff and thyristor switching inrush current of the thyristor switching switch; the temperature recorder measures the temperature rise of the thyristor switching switch; in a general manual switching thyristor switch, if a thyristor switching switch is subjected to a power-on and power-off life test for 10 to 100 ten thousand times, a large amount of labor and time are consumed for manual switching, switching response time, switching times and switching inrush current value cannot be automatically recorded, a thyristor to be tested is short-circuited and punctured or cannot be effectively triggered, and a special device is needed for detection and identification.
Therefore, the above problems are further improved.
SUMMERY OF THE UTILITY MODEL
The utility model mainly aims to provide a multifunctional thyristor switching switch detection device.A controller adopts ARM + FPGA dual CPU processors to synchronize switching on-off response time Ton, switching off response time Toff, transient inrush current value of thyristor switching, temperature rise of radiating fins, terminals and bus joints of a thyristor switching device and the like of a thyristor switching device to be detected in a high-speed real-time manner and displays the switching on-off response time Ton, the switching off response time Toff, the transient inrush current value of thyristor switching, the temperature rise of the radiating fins, the terminals and the bus joints of the thyristor switching device on a liquid crystal touch screen, so that the use frequency of a traditional oscilloscope, an electric energy quality analyzer and a temperature recorder is reduced, the working efficiency is greatly improved, and the investment of special detection equipment is saved.
The utility model also aims to provide a multifunctional thyristor switching switch detection device which automatically records the switching faults and switching times of the tested thyristor and the temperature rise curves of the capacitor and the thyristor.
The utility model also aims to provide a multifunctional thyristor switching switch detection device, which adopts SVG to compensate the capacitive reactive current of a capacitor in real time and in situ to greatly reduce the power supply power required by the device, greatly reduces the specifications of the power requirements of a cable, the power supply power, a power supply main switch and a three-phase electric voltage regulator, reduces the loss, reduces the production test cost and the equipment investment cost, and simultaneously, the SVG can emit 2-25 harmonics to simulate the influence on the inrush current value and the temperature rise of the capacitor and the thyristor switching device in different harmonic environments.
In order to achieve the above object, the present invention provides a multifunctional thyristor switch detection device for detecting a thyristor switch, including a three-phase electric voltage regulator and a (display) controller, wherein the three-phase electric voltage regulator is electrically connected to the controller, wherein:
the first path of the output end of the three-phase electric voltage regulator is electrically connected with the static var generator through a first current transformer (a current acquisition terminal of the SVG is connected with the first current transformer, and the total current, namely the current of the SVG and the total current of the capacitor bank loop, is detected in real time) and is electrically connected with the thyristor to be tested through the first current transformer;
the output end of the thyristor to be tested is electrically connected with the capacitor bank;
the voltage acquisition end of controller with the output electric connection of three-phase electric voltage regulator (the controller detects the output voltage of three-phase electric voltage regulator, the input voltage of thyristor or condenser that awaits measuring promptly), the current acquisition end of controller and second current transformer electric connection (can detect the electric current in the return circuit that the thyristor or the condenser of awaiting measuring were thrown in real time), the temperature acquisition end of controller is external a plurality of temperature sensor (temperature sensor pastes some temperature parameters in the fin, binding post, shell, capacitor case, the capacitor binding post etc. of the thyristor or condenser of awaiting measuring), the communication end (RS485) of controller sets up with the touch-sensitive screen of communication end electric connection (some relevant parameters of SVG setting accessible (demonstration) controller), the thyristor trigger end of controller and the trigger end electric connection of the thyristor that awaits measuring (when the trigger end electric connection of the thyristor or condenser of awaiting measuring And after a 12V trigger pulse signal of the controller is received, triggering and conducting the thyristor to be tested).
As a further preferable technical solution of the above technical solution, an output end of the first current transformer is electrically connected to the static var generator through a first fused knife switch;
the output end of the first current transformer is electrically connected with the multi-input multi-output upper binding post sequentially through a second knife-fuse switch, the second current transformer and the first alternating current contactor, the two ends of the first alternating current contactor are connected with the second alternating current contactor in parallel, and the output end of the multi-input multi-output upper binding post is electrically connected with the input end of the thyristor to be tested.
As a further preferred technical solution of the above technical solution, an output end of the thyristor to be tested is electrically connected to an input end of the multiple-input multiple-output lower connection post, a first path of an output end of the multiple-input multiple-output lower connection post is electrically connected to the three-phase capacitor of the capacitor bank through a third ac contactor, a second path of the output end of the multiple-input multiple-output lower connection post is electrically connected to the single-phase capacitor of the capacitor bank through a fourth ac contactor, and a third path of the output end of the multiple-input multiple-output lower connection post is electrically connected to the fast discharge resistor through a fifth ac contactor.
As the further preferred technical scheme of above-mentioned technical scheme, the output of controller step up the end with the step up end electric property of three-phase electric voltage regulator links to each other, the output step down end of controller links to each other with the step down end electric property of three-phase electric voltage regulator, the relay of controller respectively with first ac contactor, second ac contactor, third ac contactor, fourth ac contactor and fifth ac contactor's control coil electric connection (the actuation of control ac contactor or separating brake to control corresponding capacitor bank or return circuit).
As a further preferred technical scheme of the above technical scheme, the three-phase electric voltage regulator is connected with a three-phase power supply, the input end of the three-phase power supply is electrically connected with the wire inlet end of the circuit breaker through a primary cable, and the wire outlet end of the circuit breaker is electrically connected with the input end of the three-phase electric voltage regulator.
Drawings
Fig. 1 is a circuit diagram of a multifunctional thyristor switch detection device of the utility model.
The reference numerals include: the device comprises a 1-three-phase electric voltage regulator, a 2-first current transformer, a 31-first fuse switch, a 32-second fuse switch, a 4-second current transformer, a 5-first alternating current contactor, a 6-second alternating current contactor, a 7-temperature sensor, an 8-multiple-input multiple-output upper binding post, a 9-thyristor to be tested, a 10-multiple-input multiple-output lower binding post, a 11-static var generator, a 12-third alternating current contactor, a 13-fourth alternating current contactor, a 14-fifth alternating current contactor, a 15-fast discharge resistor, a 16-capacitor bank and a 17-controller.
Detailed Description
The following description is presented to disclose the utility model so as to enable any person skilled in the art to practice the utility model. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the utility model, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the utility model.
The utility model discloses a multifunctional thyristor switching switch detection device, and the specific embodiment of the utility model is further described by combining the preferred embodiment.
In the embodiment of the present invention, those skilled in the art note that the thyristor to be tested, the three-phase power supply, the circuit breaker, and the like, which are related to the present invention, can be regarded as the prior art.
Preferred embodiments.
The utility model discloses a multifunctional thyristor switch detection device, which is used for detecting a thyristor switch, and comprises a three-phase electric voltage regulator 1 and a (display) controller 17, wherein the three-phase electric voltage regulator 1 is electrically connected with the controller 17, and the three-phase electric voltage regulator comprises:
the first path of the output end of the three-phase electric voltage regulator 1 is electrically connected with the static var generator 11 through a first current transformer 2 (a current acquisition terminal of the SVG is connected with the first current transformer to detect total current in real time, namely the current of the SVG and the total current of a capacitor bank loop), and the first path of the output end of the three-phase electric voltage regulator 1 is electrically connected with the thyristor to be tested 9 through the first current transformer 2;
the output end of the thyristor to be tested 9 is electrically connected with the capacitor bank 16;
the voltage acquisition end of the controller 17 is electrically connected with the output end of the three-phase electric voltage regulator 1 (the controller detects the output voltage of the three-phase electric voltage regulator, namely the input voltage of the thyristor or the capacitor to be detected), the current acquisition end of the controller 17 is electrically connected with the second current transformer 4 (the current of the loop switched by the thyristor or the capacitor bank to be detected can be detected in real time), the temperature acquisition end of the controller 17 is externally connected with a plurality of temperature sensors 7 (the temperature sensors 7 are attached to the radiating fins, the connecting terminals, the shell, the capacitor connecting terminals and other places of the thyristor and the capacitor to be detected), the communication end (RS485) of the controller 17 is electrically connected with the communication end of the static var generator 11 (some relevant parameters of SVG are set by a touch screen of the controller (display), the trigger end of the thyristor of the controller 17 is electrically connected with the trigger end of the thyristor 9 to be tested (when the thyristor to be tested receives the 12V trigger pulse signal of the controller, the thyristor to be tested is triggered and conducted).
Specifically, the output end of the first current transformer 2 is electrically connected to the static var generator 11 through a first fused knife switch 31;
the output end of the first current transformer 2 is electrically connected with the multi-input multi-output upper binding post 8 sequentially through the second knife-fuse switch 32, the second current transformer 4 and the first alternating current contactor 5, the two ends of the first alternating current contactor 4 are connected with the second alternating current contactor 5 in parallel, and the output end of the multi-input multi-output upper binding post 8 is electrically connected with the input end of the thyristor 9 to be tested.
More specifically, the output end of the thyristor 9 to be tested is electrically connected to the input end of the multiple input multiple output lower connector post 10, the first path of the output end of the multiple input multiple output lower connector post 10 is electrically connected to the three-phase capacitor of the capacitor bank 16 through the third ac contactor 12, the second path of the output end of the multiple input multiple output lower connector post 10 is electrically connected to the single-phase capacitor of the capacitor bank 16 through the fourth ac contactor 13, and the third path of the output end of the multiple input multiple output lower connector post 10 is electrically connected to the fast discharge resistor 15 through the fifth ac contactor 14.
Further, the output of controller 17 step up the end with the end electrical property that steps up of three-phase electric voltage regulator links to each other, the output step down end of controller 17 links to each other with the step down end electrical property of three-phase electric voltage regulator, the relay of controller 17 is respectively with first ac contactor 5, second ac contactor 6, third ac contactor 12, fourth ac contactor 13 and fifth ac contactor 14's control coil electric connection (the actuation of control ac contactor perhaps divides the floodgate to control corresponding capacitor bank or return circuit).
Furthermore, the three-phase electric voltage regulator 1 is connected with a three-phase power supply, the input end of the three-phase power supply is electrically connected with the wire inlet end of the circuit breaker through a primary cable, and the wire outlet end of the circuit breaker is electrically connected with the input end of the three-phase electric voltage regulator.
Preferably, SVG detects the electric current of first mutual-inductor in real time to the capacitive reactive current that compensation thyristor switching condenser produced, SVG sends the perception reactive current, and the active loss sum when condenser, SVG full power operation of SVG is less than condenser or SVG apparent power 4%, can reduce three-phase electric voltage regulator, primary circuit cable, protection switch, fuse capacity by a wide margin like this, the equipment investment has been practiced thrift, SVG has compensated reactive current simultaneously, reactive current has been reduced by a wide margin, thereby the loss of generating heat of electric current has been reduced.
Preferably, the static var generator SVG generates heat in loss during working (the power is 2-4% during SVG running), and the heat generated by the SVG can be used as a heat source during a thyristor or capacitor temperature rise aging test, so that the heat dissipated by the SVG is effectively utilized, and the energy consumption of a system is reduced.
Preferably, capacitor bank can be replaced by the ageing condenser of temperature rise, and the ageing condenser of temperature rise, inrush current, high temperature life of measurable quantity condenser have increased the multi-functional reuse nature of device.
Preferably, the temperature probes of the device can measure the temperature at the thyristor fins, terminals, bus bar connections.
Preferably, the static var generator SVG of the device can generate harmonic current to simulate whether the thyristor switching device can stably work in the environment with large grid voltage and current harmonic ratio, and whether zero-crossing switching can be performed to reduce switching inrush current.
Preferably, the principle of the utility model is as follows: the controller controls the input of the corresponding capacitor bank according to the capacitor capacity set value, then the controller collects the output voltage of the three-phase electric voltage regulator in real time and controls the output voltage of the three-phase electric voltage regulator to reach the set value. The controller outputs a 12V thyristor trigger control signal, and simultaneously, the controller starts timing until the thyristor is triggered to conduct and stops timing, wherein the value is the trigger conduction response time Ton of the thyristor, the controller synchronously collects the current of a current transformer TA2 at high speed, the current peak value of the capacitor branch is the inrush current peak value of the thyristor at the moment that the thyristor is triggered to conduct, and if the inrush current peak value is less than 3 times of the rated current value of the capacitor, the thyristor switching switch conforms to the 6.5.3.3 inrush current limit value of GB/T29312-2012. The controller stops outputting the 12V trigger signal to start timing until the thyristor switch is turned off, the controller detects that the current of the current transformer TA2 is 0, and the controller stops timing at the moment, wherein the time is the breaking response time of the thyristor Toff. And the thyristor switching switch is respectively electrified for 2s under 1.1 and 0.85 times of rated voltage, the interval is 5s, the switching test is carried out after 50 times of each, and if the inrush current peak value is less than 3 times of rated current of the capacitor, the thyristor switching switch meets the GB/T29312-2012 standard. When the thyristor switching switch is in an electric service life, the device is set to be in an electric service life mode on the touch display screen, the controller controls the output voltage of the three-phase electric voltage regulator to be a rated value and outputs a 12V signal to trigger the thyristor to be tested, the controller detects the inrush current value when the thyristor is conducted, the current transformer is electrified for 2s and then controls the quick discharge resistor to be put into the accelerating capacitor to discharge for about 30s, the internal voltage of the capacitor is lower than 50V, if the thyristor is triggered and the inrush current value is smaller than 3 times of the rated current value of the capacitor, the capacitor is effectively marked as 1 time, and if the thyristor is not triggered or the inrush current value is larger than 3 times, the capacitor is marked as invalid 1 time. The controller controls the thyristor to switch for 1 ten thousand times, 10 ten thousand times and 100 ten thousand times. The utility model can automatically record the switching times, the switching inrush current value and the switching response time, reduces the manual operation of an oscilloscope, a counter, an electric energy quality analyzer and a manual switching capacitor, reduces the operation difficulty and greatly improves the working efficiency.
It should be noted that the technical features of the thyristor to be tested, the three-phase power supply, the circuit breaker and the like related to the present patent application should be regarded as the prior art, and the specific structure, the operating principle, the control mode and the spatial arrangement mode of the technical features may be conventional choices in the field, and should not be regarded as the utility model point of the present patent, and the present patent is not further specifically described in detail.
It will be apparent to those skilled in the art that modifications and equivalents may be made in the embodiments and/or portions thereof without departing from the spirit and scope of the present invention.
Claims (5)
1. The utility model provides a multi-functional thyristor on-off switch detection device for detect the on-off switch of thyristor, its characterized in that, including the electronic voltage regulator of three-phase and controller, the electronic voltage regulator of three-phase with controller electric connection, wherein:
the first path of the output end of the three-phase electric voltage regulator is electrically connected with the static var generator through a first current transformer, and the first path of the output end of the three-phase electric voltage regulator is electrically connected with the thyristor to be tested through the first current transformer;
the output end of the thyristor to be tested is electrically connected with the capacitor bank;
the voltage acquisition end of controller with the output electric connection of three-phase electric voltage regulator, the current acquisition end and the second current transformer electric connection of controller, the external a plurality of ways temperature sensor of temperature acquisition end of controller, the communication end and the communication end electric connection of SVG of controller.
2. The multifunctional thyristor switch detection device according to claim 1, wherein the output end of the first current transformer is electrically connected to the static var generator through a first knife switch;
the output end of the first current transformer is electrically connected with the multi-input multi-output upper binding post sequentially through a second knife-fuse switch, the second current transformer and the first alternating current contactor, the two ends of the first alternating current contactor are connected with the second alternating current contactor in parallel, and the output end of the multi-input multi-output upper binding post is electrically connected with the input end of the thyristor to be tested.
3. The device as claimed in claim 2, wherein the output terminal of the thyristor under test is electrically connected to the input terminal of a multi-input multi-output lower pin, the first path of the output terminal of the multi-input multi-output lower pin is electrically connected to the three-phase capacitor of the capacitor bank through a third ac contactor, the second path of the output terminal of the multi-input multi-output lower pin is electrically connected to the single-phase capacitor of the capacitor bank through a fourth ac contactor, and the third path of the output terminal of the multi-input multi-output lower pin is electrically connected to the fast discharge resistor through a fifth ac contactor.
4. The device as claimed in claim 3, wherein the output boost terminal of the controller is electrically connected to the boost terminal of the three-phase voltage regulator, the output buck terminal of the controller is electrically connected to the buck terminal of the three-phase voltage regulator, and the relay of the controller is electrically connected to the control coils of the first ac contactor, the second ac contactor, the third ac contactor, the fourth ac contactor and the fifth ac contactor, respectively.
5. The device as claimed in claim 3, wherein the three-phase electric voltage regulator is connected to a three-phase power supply, an input terminal of the three-phase power supply is electrically connected to an input terminal of the circuit breaker via a primary cable, and an output terminal of the circuit breaker is electrically connected to an input terminal of the three-phase electric voltage regulator.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202121753852.XU CN215526408U (en) | 2021-07-29 | 2021-07-29 | Multifunctional thyristor switching switch detection device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202121753852.XU CN215526408U (en) | 2021-07-29 | 2021-07-29 | Multifunctional thyristor switching switch detection device |
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| CN215526408U true CN215526408U (en) | 2022-01-14 |
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| CN202121753852.XU Active CN215526408U (en) | 2021-07-29 | 2021-07-29 | Multifunctional thyristor switching switch detection device |
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