CN112462252A - Synchronous switch relay calibration platform and calibration method - Google Patents
Synchronous switch relay calibration platform and calibration method Download PDFInfo
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- CN112462252A CN112462252A CN202011322411.4A CN202011322411A CN112462252A CN 112462252 A CN112462252 A CN 112462252A CN 202011322411 A CN202011322411 A CN 202011322411A CN 112462252 A CN112462252 A CN 112462252A
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- 230000001360 synchronised effect Effects 0.000 title claims abstract description 86
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000004891 communication Methods 0.000 claims abstract description 41
- 238000001514 detection method Methods 0.000 claims abstract description 34
- 230000001052 transient effect Effects 0.000 claims description 21
- 238000005520 cutting process Methods 0.000 claims description 20
- 239000003990 capacitor Substances 0.000 abstract description 7
- 238000012545 processing Methods 0.000 abstract description 3
- 230000002035 prolonged effect Effects 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 230000002457 bidirectional effect Effects 0.000 description 21
- 238000006243 chemical reaction Methods 0.000 description 8
- 230000005540 biological transmission Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
Abstract
The invention discloses a synchronous switch relay calibration platform and a calibration method. The invention relates to a synchronous switch relay calibration platform, which comprises: the calibration platform is used for connecting a synchronous switch product, and the synchronous switch product comprises a synchronous switch and a relay; the calibration platform comprises: the device comprises a platform 485 communication circuit, a control signal detection module, a switching signal detection module and a calibration platform CPU. The invention has the beneficial effects that: the control signal and the relay switching-in/switching-off signal are acquired through calibration detection, switching delay is calculated according to the time interval of the two signals and is written into a CPU (central processing unit) of a synchronous switch, and 485 communication is adopted for command sending and writing, so that the zero-crossing switching error of each relay is smaller than 0.1ms, the switching inrush current of a capacitor is greatly reduced, the reliability of a product is improved, and the service lives of the capacitor, a circuit breaker and the relay are prolonged.
Description
Technical Field
The invention relates to the field of synchronous switch relays, in particular to a synchronous switch relay calibration platform and a calibration method, which are applied to the synchronous switch zero-crossing switching calibration of a reactive power compensation device in the power industry.
Background
From the future development, the reactive compensation switching device has the advantages of being superior to the existing compound switch and relay switch in cost and reliability, energy-saving, environment-friendly, economical and durable, is an ideal updated product of an alternating current contactor and the compound switch, and the synchronous switch must replace the compound switch and the relay switch to become the mainstream of the reactive compensation capacitor switching switch.
The synchronous switch is characterized in that a single chip microcomputer collects current and voltage zero-crossing signals to control the relay to be closed and disconnected, the relay is guaranteed to be put in at a voltage zero-crossing point, and the current zero-crossing point is cut off.
The traditional technology has the following technical problems:
although the switching delay error of the commitment relay given by a manufacturer can be controlled within 1ms, the difference of the actual processing technology, the difference of electronic elements, sampling, calculation and control and the error can also be controlled within 1.5ms, and if the average value is adopted for switching delay, the service life of the relay with large error in the actual working process is greatly reduced. Therefore, it is necessary to perform delay calibration on each path of relay.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a synchronous switch relay calibration platform and a calibration method, wherein the switching delay of three paths of relays of a synchronous switch is calibrated in the production process, so that the zero-crossing switching error of each path of relay is less than 0.1ms, the switching inrush current of a capacitor is greatly reduced, the product reliability is improved, and the service lives of the capacitor, a circuit breaker and the relay are prolonged.
In order to solve the above technical problem, the present invention provides a calibration platform for a synchronous switch relay, comprising: the calibration platform is used for connecting a synchronous switch product, and the synchronous switch product comprises a synchronous switch and a relay; the calibration platform comprises: the device comprises a platform 485 communication circuit, a control signal detection module, a switching signal detection module and a calibration platform CPU; the platform 485 communication circuit is used for communicating with the synchronous switch, the control signal detection module is used for detecting a control signal sent by the synchronous switch to the relay, and the switching signal detection module is used for detecting a switching signal of the relay; the calibration platform CPU calculates switching delay, sends a switching command through the platform 485 communication circuit, and writes the switching delay into the synchronous switch through the platform 485 communication circuit.
In one embodiment, the calibration platform further comprises a display module, the display module is electrically connected with the calibration platform CPU, and the display module is configured to display the switching delay.
In one embodiment, the switching signal comprises a switching signal and a cutting signal of the relay.
In one embodiment, the switching delay includes a switching-in delay and a switching-out delay of the relay.
In one embodiment, the specific method for calculating the switching delay by the calibration platform CPU is as follows: and calculating the time interval of the control signal and the switching signal of the relay.
In one embodiment, the control signals include an on control signal and an off control signal.
In one embodiment, the 485 communication circuit comprises a bidirectional level conversion chip, a first bidirectional transient diode, a second bidirectional transient diode, a third bidirectional transient and a diode resistor, wherein one end of the second bidirectional transient diode is connected with a first pin of the bidirectional level conversion chip, the other end of the second bidirectional transient diode is connected with the resistor, one end of the first bidirectional transient diode is connected with the first pin of the bidirectional level conversion chip, the other end of the first bidirectional transient diode is grounded, one end of the third bidirectional transient diode is connected with a second pin of the bidirectional level conversion chip, and the other end of the third bidirectional transient diode is grounded.
Based on the same inventive concept, the invention also provides a method for calibrating the synchronous switch relay based on any one of the synchronous switch relay calibration platforms, which is characterized by comprising the following steps: the calibration platform gives an input control signal, the input signal command is sent to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the input control signal, and the control signal detection module detects that the input control signal starts timing; the input control signal controls the drive circuit to enable the relay to be attracted, the switching signal detection module detects that the input signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the input calibration is finished.
In one embodiment, the calibration platform further provides a cutting control signal, the cutting control signal is sent to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the cutting control signal, and the control signal detection module detects that the cutting control signal starts to time; the cutting control signal controls the driving circuit to disconnect the relay, the switching signal detection module detects that the cutting signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the cutting calibration is finished.
In one embodiment, the method further comprises the following steps: and displaying the obtained delay time through the display module.
The invention has the beneficial effects that:
the control signal and the relay switching-in/switching-off signal are acquired through calibration detection, switching delay is calculated according to the time interval of the two signals and is written into a CPU (central processing unit) of a synchronous switch, and 485 communication is adopted for command sending and writing, so that the zero-crossing switching error of each relay is smaller than 0.1ms, the switching inrush current of a capacitor is greatly reduced, the reliability of a product is improved, and the service lives of the capacitor, a circuit breaker and the relay are prolonged.
Drawings
Fig. 1 is a schematic structural diagram of a synchronous switch relay calibration platform of the present invention.
Fig. 2 is a schematic diagram illustrating the detection principle of the control signal in the synchronous switch relay calibration platform according to the present invention.
Fig. 3 is a schematic diagram of the detection principle of the switching signal in the synchronous switch relay calibration platform according to the present invention.
Fig. 4 is a schematic circuit diagram of a platform 485 communication circuit in the synchronous switch relay calibration platform of the present invention.
Detailed Description
The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.
The invention designs a calibration platform based on a finished product synchronous switch circuit board, sends a switching command to a single chip microcomputer of the synchronous switch circuit board, calibrates, detects and acquires a control signal and a relay switching-in/switching-off signal, calculates switching delay according to the time interval of the two signals and writes the switching delay into a CPU of a synchronous switch, and the command sending and the command writing adopt 485 communication.
The invention has the main conception that how the calibration platform accurately detects the switching delay of the relay based on the finished product of the synchronous switch circuit board and automatically writes the delay time into the CPU of the synchronous switch. The position and the communication mode of the sampling point are determined from the initial design stage, the only communication mode is 485 communication based on the finished circuit board of the synchronous switch, and therefore the communication of the calibration platform is based on 485 communication to carry out hardware and program design. For the selection of sampling points, control signals output by the single chip microcomputer of the synchronous switch circuit board are used for controlling the driving circuit to carry out switching work of the relay, a certain delay is included in the switching delay for the driving circuit, all sampling points are collected from signals of an output port of the single chip microcomputer, and switching signals are collected through contacts of the relay. The whole delay time is from the time when the singlechip gives a control signal to start timing to the time when the singlechip receives a relay contact action signal.
Referring to fig. 1, a synchronous switching relay calibration platform includes: the calibration platform is used for connecting a synchronous switch product, and the synchronous switch product comprises a synchronous switch and a relay; the calibration platform comprises: the device comprises a platform 485 communication circuit, a control signal detection module, a switching signal detection module and a calibration platform CPU; the platform 485 communication circuit is used for communicating with the synchronous switch, the control signal detection module is used for detecting a control signal sent by the synchronous switch to the relay, and the switching signal detection module is used for detecting a switching signal of the relay; the calibration platform CPU calculates switching delay, sends a switching command through the platform 485 communication circuit, and writes the switching delay into the synchronous switch through the platform 485 communication circuit.
The calibration delay time is conveniently observed by a tester, so that the calibration accuracy can be artificially judged. The synchronous switch relay calibration platform further comprises a display module, the display module is electrically connected with the calibration platform CPU, and the display module is used for displaying the switching delay.
It is understood that the relay is divided into two processes, the above-mentioned related names include both processes and possibilities. That is, the switching signal includes a switching signal and a cutting signal of the relay. The switching delay comprises the switching delay and the cutting delay of the relay. The control signals include an on control signal and an off control signal.
The specific method for calculating the switching delay of the calibration platform CPU is as follows: and calculating the time interval of the control signal and the switching signal of the relay.
Referring to fig. 2, for the detection of the control signal, because the synchronous switch adopts a single-coil magnetic latching relay, the control signal KA in + is at a high level, KA in-is at a low level, the control signal KA in + is at a low level, KA in-is at a high level, the relay is disconnected, KA in + + and KA in-are connected to an IO port of the single chip, and software is pulled up. Therefore, when the KA and the KB acquire signals, if the signals are suction signals, the control signal KA in + is at a high level, KA in-is at a low level, Q1 is switched on, KA in + + is pulled down to be at a low level, and KA in-is at a high level, and the single chip microcomputer can judge that the single chip microcomputer of the synchronous switch gives a relay control signal as an input signal according to the states of KA in + + and KA in-.
Referring to fig. 3, for detection of switching signals, a universal meter can be used for testing resistance values of the relay when distinguishing a pull-in off state, for how the switching signals of the relay can be collected by a calibration platform, the relay state can be judged according to the detection voltage alternation edge of a port of a single chip microcomputer, T5, T6, T7, T8, T9 and T10 are detection signals of three relays respectively, and when a relay contact is connected with T8 and T5, for example, one path of KA is used, KA out + + is connected with an IO port of the single chip microcomputer, and software is pulled up. And when the relay does not receive the pull-in control signal, the KA out + + is high level. When the relay receives the pull-in control signal, Q7 is turned on, and KA out + + is pulled to low level. And the singlechip records the delay time from the control signal to the switching signal according to the alternating edge.
Referring to fig. 4, the 485 communication circuit includes a bidirectional level conversion chip U2, a bidirectional transient diode (D1, D2, D3), and a resistor R6, one end of the bidirectional transient diode D2 is connected to a pin 13 of the bidirectional level conversion chip U2, the other end is connected to the resistor R6, one end of the bidirectional transient diode D1 is connected to the pin 13 of the bidirectional level conversion chip U6, the other end is grounded, one end of the bidirectional transient diode D3 is connected to a pin 12 of the bidirectional level conversion chip U6, and the other end is grounded.
The 485 communication circuit has the advantages of good noise interference resistance, high transmission rate and the like, the maximum transmission distance standard value is 4000 feet, and the 485 communication circuit has multi-station capability, so that a user can conveniently establish a device network by using a single RS-485 interface.
The RS-485 interface becomes the preferred serial interface due to the advantages of good noise interference resistance, long transmission distance, multi-station capability and the like. Because the half-duplex network formed by the RS485 interfaces generally only needs two connecting wires, the RS485 interfaces all adopt shielded twisted-pair transmission.
Based on the same inventive concept, the invention also provides a calibration method of the synchronous switch relay calibration platform, which comprises the following steps: the calibration platform gives an input control signal, the input signal command is sent to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the input control signal, and the control signal detection module detects that the input control signal starts timing; the input control signal controls the drive circuit to enable the relay to be attracted, the switching signal detection module detects that the input signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the input calibration is finished.
In one embodiment, the calibration platform further provides a cutting control signal, the cutting control signal is sent to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the cutting control signal, and the control signal detection module detects that the cutting control signal starts to time; the cutting control signal controls the driving circuit to disconnect the relay, the switching signal detection module detects that the cutting signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the cutting calibration is finished.
In order to facilitate the tester to observe the delay time of calibration, so as to artificially judge the accuracy of calibration, the calibration method further comprises: and displaying the obtained delay time through a display module.
Of course, in the actual calibration process, some preparation steps are also included: when the control signal of the calibration platform is detected to be connected with the control signal of the synchronous switch, the switching signal is detected to be connected with the switching signal of the synchronous switch. The 485 communication is connected with the 485 communication of the synchronous switch, and the relay calibration is carried out after power supply is provided for the synchronous switch and the calibration platform.
The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.
Claims (10)
1. A synchronous switch relay calibration platform, comprising: the calibration platform is used for connecting a synchronous switch product, and the synchronous switch product comprises a synchronous switch and a relay; the calibration platform comprises: the device comprises a platform 485 communication circuit, a control signal detection module, a switching signal detection module and a calibration platform CPU; the platform 485 communication circuit is used for communicating with the synchronous switch, the control signal detection module is used for detecting a control signal sent by the synchronous switch to the relay, and the switching signal detection module is used for detecting a switching signal of the relay; the calibration platform CPU calculates switching delay, sends a switching command through the platform 485 communication circuit, and writes the switching delay into the synchronous switch through the platform 485 communication circuit.
2. The synchronous switch relay calibration platform of claim 1, further comprising a display module, the display module being electrically connected to the calibration platform CPU, the display module being configured to display the switching delay.
3. The synchronous switch relay calibration platform of claim 1, wherein the switching signals comprise a throw signal and a cut signal of a relay.
4. The synchronous switch relay calibration platform of claim 1, wherein the switching delay comprises a throw-in delay and a throw-out delay of the relay.
5. The synchronous switch relay calibration platform of claim 1, wherein the specific method for calculating the switching delay by the calibration platform CPU is as follows: and calculating the time interval of the control signal and the switching signal of the relay.
6. The synchronous switching relay calibration platform of claim 1, wherein the control signals comprise an on control signal and an off control signal.
7. The synchronous switch relay calibration platform of claim 1, wherein the 485 communication circuit comprises a bi-directional level shift chip, a first bi-directional transient diode, a second bi-directional transient diode, a third bi-directional transient diode and a diode resistor, wherein one end of the second bi-directional transient diode is connected to the first pin of the bi-directional level shift chip, the other end of the second bi-directional transient diode is connected to the resistor, one end of the first bi-directional transient diode is connected to the first pin of the bi-directional level shift chip, the other end of the first bi-directional transient diode is grounded, and one end of the third bi-directional transient diode is connected to the second pin of the bi-directional level shift chip, and the other.
8. A method for calibrating a synchronous switching relay based on the synchronous switching relay calibration platform of any one of claims 1 to 7, comprising: the calibration platform gives an input control signal, the input signal command is sent to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the input control signal, and the control signal detection module detects that the input control signal starts timing; the input control signal controls the drive circuit to enable the relay to be attracted, the switching signal detection module detects that the input signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the input calibration is finished.
9. The synchronous switch relay calibration method according to claim 8, further comprising the step of giving a cut-off control signal by the calibration platform, wherein the cut-off control signal is given to the synchronous switch CPU through the platform 485 communication circuit, the synchronous switch CPU executes the cut-off control signal, and the control signal detection module detects that the cut-off control signal starts to time; the cutting control signal controls the driving circuit to disconnect the relay, the switching signal detection module detects that the cutting signal of the relay is timed, the calibration platform CPU writes the obtained delay time into the synchronous switch CPU through the platform 485 communication circuit, and the cutting calibration is finished.
10. The synchronous switching relay calibration method of claim 8, further comprising: and displaying the obtained delay time through the display module.
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| CN202011322411.4A CN112462252A (en) | 2020-11-23 | 2020-11-23 | Synchronous switch relay calibration platform and calibration method |
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