CN112986886A - High-voltage nuclear phase instrument calibration device and method - Google Patents
High-voltage nuclear phase instrument calibration device and method Download PDFInfo
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Abstract
The invention discloses a high-voltage phase detector calibration device and a method, wherein the device comprises a VFD keyboard and two detection channels; each path of detection channel comprises a program-controlled standard voltage source, a power amplifier and a self-boosting standard voltage transformer; the output end of the VFD keyboard is respectively connected with the program-controlled standard power supply in each road detection channel, and is used for quickly inputting set parameters through a digital keyboard and automatically transmitting the set parameters to the program-controlled standard voltage supply; in each detection channel, the output end of the program-controlled standard power supply is connected with a self-boosting standard voltage transformer through a power amplifier, the output end of the self-boosting standard voltage transformer is connected with a high-voltage nuclear phase instrument to be detected, and the output end of the self-boosting standard voltage transformer is further connected with the feedback input end of the program-controlled standard voltage source. The calibration device and the calibration method provided by the invention can effectively improve the working efficiency of the calibration of the high-voltage nuclear phase instrument.
Description
Technical Field
The invention relates to a high-voltage phase detector, in particular to a high-voltage phase detector calibration device and method.
Background
The phase sequence inversion of the power supply occurs during the switching of the power supply, which damages electrical and mechanical equipment and is important for systems requiring the parallel operation of the power supply. The high-voltage phase detector enables the high-voltage phase detection work which is dangerous and indispensable to become safe and reliable, the indication is visual and clear, and the high-voltage phase detector is convenient to carry and is an indispensable tool for high-voltage electricians.
The high-voltage phase detector is an important guarantee tool for monitoring the normal operation of a power grid, so that the regular metering and detecting work of the high-voltage phase detector is particularly important. The existing detection means for the high-voltage nuclear phase instrument is to use a voltage regulator, a booster, a high-voltage standard mutual inductor, a digital voltmeter, a phase meter, a lead and other electric elements to combine and wire connection for detection; during calibration, the voltage regulator, the booster, the high-voltage standard mutual inductor, the digital voltmeter and the phase meter are required to be connected one by one, and different voltage angles are required to be obtained by a plurality of voltage regulators in a phase vector superposition mode when other phase sequences are detected.
The existing method for detecting the high-voltage phase checking instrument has the defects of complex wiring, complex operation and use, insufficient accurate value of output voltage, incapability of continuously adjusting the phase by only 15 degrees, 30 degrees, 45 degrees, 60 degrees, 90 degrees, 180 degrees and the like, particularly phase angle transformation is carried out, the detection of one high-voltage phase checking instrument can be finished by adjusting the wiring rear part every time and repeatedly adjusting the measuring connecting wire for many times, the measuring and detecting work efficiency is seriously influenced, and the detection of each phase checking instrument can be finished by more than 1 hour. With the increase of the use number of the high-voltage phase detector in recent years, particularly the level of 6-10 kV, the original calibration mode can not completely meet the requirement of the high-voltage phase detector on measuring and calibrating capacity.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides a high-voltage nuclear phase instrument calibration device and method, and effectively improves the working efficiency of high-voltage nuclear phase instrument calibration.
The purpose of the invention is realized by the following technical scheme: a high-voltage phase checking instrument calibration device comprises a VFD keyboard and two detection channels; each path of detection channel comprises a program-controlled standard voltage source, a power amplifier and a self-boosting standard voltage transformer;
the output end of the VFD keyboard is respectively connected with the program-controlled standard power supply in each road detection channel, and is used for quickly inputting set parameters through a digital keyboard and automatically transmitting the set parameters to the program-controlled standard voltage supply;
in each detection channel, the output end of the program-controlled standard power supply is connected with a self-boosting standard voltage transformer through a power amplifier, the output end of the self-boosting standard voltage transformer is connected with a high-voltage nuclear phase instrument to be detected, and the output end of the self-boosting standard voltage transformer is further connected with the feedback input end of the program-controlled standard voltage source.
Preferably, the calibration apparatus further includes a linear power supply, and the linear power supply is respectively connected to the power amplifiers in each of the detection channels. The linear power supply adopts a ring transformer step-down rectification technology to provide a pure power supply for the power amplifier, and digital signal interference introduced by the digital power supply to the power amplifier is avoided.
Preferably, the program-controlled standard power supply comprises a digital signal source and a PID regulating circuit;
the PID regulating circuit is used for comparing the signal generated by the digital signal source with a standard voltage feedback signal generated by a self-boosting standard transformer and automatically correcting the signal;
the digital signal source comprises an ARM micro-control processor and a synchronous processing module; the synchronous processing module comprises a CPLD chip and a DAC module; the input end of the ARM control processor is connected with the VFD keyboard, the output end of the ARM control processor is connected with the signal input end of the PID adjusting circuit sequentially through the CPLD chip and the DAC module, the feedback input end of the PID adjusting circuit is connected with the output end of the self-boosting standard voltage transformer, and the output end of the PID adjusting circuit is connected with the power amplifier.
Preferably, the synchronous processing modules of the digital signal sources in the two detection channels are connected through a synchronous signal line, so that signal synchronization between the two detection channels is ensured.
A high-voltage nuclear phase instrument calibration method comprises the following steps:
s1, a user sets voltage and phase parameters needing to be output and measured through a VFD keyboard, and after the voltage and phase parameters are confirmed, the VFD keyboard transmits the parameters set by the user to a program control standard voltage source;
s2, generating a two-phase standard sinusoidal voltage signal by a digital signal source of the program-controlled voltage source according to user setting, and transmitting the two-phase standard sinusoidal voltage signal to a PID (proportion integration differentiation) regulating circuit;
s3, carrying out proportional, integral and differential processing on the standard sinusoidal voltage signal and the standard voltage feedback signal by the PID regulating circuit, and then transmitting the processed signals to a power amplifier;
s4, amplifying the weak signal to a self-boosting standard voltage transformer by the power amplifier by adopting a linear power amplification technology;
s5, the self-boosting standard voltage transformer further boosts a voltage signal to 10kV high voltage and transmits the voltage signal to a high-voltage nuclear phase instrument, meanwhile, a standard voltage feedback signal is sent back to a PID (proportion integration differentiation) regulating circuit to be precisely corrected, so that large loop feedback control of precise voltage is realized, and the output voltage is ensured to be consistent with the voltage set by a user;
and S6, recording the detection voltage amplitude and the phase parameters of the high-voltage phase checking instrument, and comparing the detection voltage amplitude and the phase parameters with the parameters set by a user to realize error calibration of the high-voltage phase checking instrument.
The invention has the beneficial effects that: (1) the invention realizes the continuous adjustment of the output standard voltage and solves the problems of inaccurate voltage adjustment and slow output of the voltage regulator;
(2) the invention realizes the continuous adjustment of the standard angle between two phases and solves the problem that the continuous phase angle adjustment cannot be realized because the included angle is obtained by adopting the power grid inherent angle phase vector superposition mode in the prior art.
(3) The invention adopts a numeric keyboard and a VFD keyboard to automatically control output signals through human-computer interaction, and solves the problem that the output value cannot be quickly set through manual regulation and pressure regulation.
(4) The invention adopts a large ring automatic feedback control technology, so that two phases of set standard voltage and phase signals can be rapidly and accurately output.
(5) The invention adopts the standard program-controlled standard voltage source and the integrated self-boosting standard mutual inductor technology to reduce the complex wiring of the traditional voltage regulator, booster, high-voltage standard mutual inductor, digital voltage gauge outfit and phase meter.
Drawings
FIG. 1 is a schematic block diagram of the system of the present invention;
FIG. 2 is a functional block diagram of a programmable standard power supply;
FIG. 3 is a flow chart of the method of the present invention.
Detailed Description
The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the following.
As shown in fig. 1, a calibration device for a high-voltage phase detector comprises a VFD keyboard and two detection channels; each path of detection channel comprises a program-controlled standard voltage source, a power amplifier and a self-boosting standard voltage transformer;
the output end of the VFD keyboard is respectively connected with the program-controlled standard power supply in each road detection channel, and is used for quickly inputting set parameters through a digital keyboard and automatically transmitting the set parameters to the program-controlled standard voltage supply;
in each detection channel, the output end of the program-controlled standard power supply is connected with a self-boosting standard voltage transformer through a power amplifier, the output end of the self-boosting standard voltage transformer is connected with a high-voltage nuclear phase instrument to be detected, and the output end of the self-boosting standard voltage transformer is further connected with the feedback input end of the program-controlled standard voltage source.
In fig. 1, one of the detection channels is used as an a-phase input of the high-voltage phase detector, the device is an a-phase device, the other channel is used as a C-phase input of the high-voltage phase detector, and the device is a C-phase device.
In an embodiment of the present application, the calibration apparatus further includes a linear power supply, and the linear power supply is respectively connected to the power amplifiers in each of the detection channels. The linear power supply adopts a ring transformer step-down rectification technology to provide a pure power supply for the power amplifier, and digital signal interference introduced by the digital power supply to the power amplifier is avoided.
In an embodiment of the present application, the programmable standard power supply includes a digital signal source and a PID adjusting circuit;
the PID regulating circuit is used for comparing the signal generated by the digital signal source with a standard voltage feedback signal generated by a self-boosting standard transformer and automatically correcting the signal;
as shown in fig. 2, the digital signal source includes an ARM micro-controller and a synchronous processing module; the synchronous processing module comprises a CPLD chip and a DAC module; the input end of the ARM control processor is connected with the VFD keyboard, the output end of the ARM control processor is connected with the signal input end of the PID adjusting circuit sequentially through the CPLD chip and the DAC module, the feedback input end of the PID adjusting circuit is connected with the output end of the self-boosting standard voltage transformer, and the output end of the PID adjusting circuit is connected with the power amplifier.
In the embodiment of the application, the synchronous processing modules of the digital signal sources in the two detection channels are connected through a synchronous signal line, and the synchronous signal line ensures and realizes the accurate synchronization of the two signals;
in the embodiment of the application, the power amplifier adopts a combined device of the class A amplifier and the class B amplifier, which depends on the bias current and the output level, of the class AB power amplifier technology, so that the working intervals of two transistors working in a push-pull working mode can be mutually covered, and the defects of the class A amplifier and the class B amplifier are overcome. The AB type power amplifier belongs to a linear power amplifier, plays a role in inhibiting even harmonic waves and ensures that an output sine power signal obtains a very low distortion value;
in the embodiment of the application, the self-boosting standard voltage transformer is used as a voltage transformer calibration standard in the error test of the transformer. The standard transformer body of the self-boosting standard voltage transformer is connected with the booster body through the inside of the electric connecting conductor; the voltage boosting and voltage checking standard is integrated. Compact structure, small volume, simple wiring and operation.
As shown in fig. 3, a calibration method for a high-voltage phase detector includes the following steps:
s1, a user sets voltage and phase parameters needing to be output and measured through a VFD keyboard, and after the voltage and phase parameters are confirmed, the VFD keyboard transmits the parameters set by the user to a program control standard voltage source;
s2, generating a two-phase standard sinusoidal voltage signal by a digital signal source of the program-controlled voltage source according to user setting, and transmitting the two-phase standard sinusoidal voltage signal to a PID (proportion integration differentiation) regulating circuit;
s3, carrying out proportional, integral and differential processing on the standard sinusoidal voltage signal and the standard voltage feedback signal by the PID regulating circuit, and then transmitting the processed signals to a power amplifier;
s4, amplifying the weak signal to a self-boosting standard voltage transformer by the power amplifier by adopting a linear power amplification technology;
s5, the self-boosting standard voltage transformer further boosts a voltage signal to 10kV high voltage and transmits the voltage signal to a high-voltage nuclear phase instrument, meanwhile, a standard voltage feedback signal is sent back to a PID (proportion integration differentiation) regulating circuit to be precisely corrected, so that large loop feedback control of precise voltage is realized, and the output voltage is ensured to be consistent with the voltage set by a user;
and S6, recording the detection voltage amplitude and the phase parameters of the high-voltage phase checking instrument, and comparing the detection voltage amplitude and the phase parameters with the parameters set by a user to realize error calibration of the high-voltage phase checking instrument.
The specific calibration method is as follows:
equation 1: voltage measurement error = ((measured value-set value) ÷ set value) + correction value
Equation 2: phase measurement error = (measured value-set value) + correction value
Measured value: the result is the electrical parameter actually measured by the high-voltage nuclear phase instrument.
Setting value: the user sets the value of the electric parameter to be output through the VFD keyboard.
Correction value: the error correction value after the system tracing calibration is used for compensating the error information of the calibration device, but the correction value is measured in advance and can be regarded as a known quantity in the application; in some embodiments, the correction values may also be ignored directly.
The calibration of the high-voltage phase checking instrument can be completed only by once wiring, complex operations such as wiring conversion and the like are not needed midway, the high-voltage phase checking instrument can be rapidly detected, the detection working efficiency is improved, and the calibration operation which can be completed within more than 1 hour can be completed within 5 minutes at present. Due to the standard program-controlled voltage source technology and the integrated design, the operation requirement of the wiring detection technology of the inspector is reduced, and the safety and effectiveness of detection are improved.
While the foregoing description shows and describes a preferred embodiment of the invention, it is to be understood, as noted above, that the invention is not limited to the form disclosed herein, but is not intended to be exhaustive or to exclude other embodiments and may be used in various other combinations, modifications, and environments and may be modified within the scope of the inventive concept described herein by the above teachings or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. The utility model provides a high pressure nuclear phase appearance calibrating device which characterized in that: the device comprises a VFD keyboard and two detection channels; each path of detection channel comprises a program-controlled standard voltage source, a power amplifier and a self-boosting standard voltage transformer;
the output end of the VFD keyboard is respectively connected with the program-controlled standard power supply in each road detection channel, and is used for quickly inputting set parameters through a digital keyboard and automatically transmitting the set parameters to the program-controlled standard voltage supply;
in each detection channel, the output end of the program-controlled standard power supply is connected with a self-boosting standard voltage transformer through a power amplifier, the output end of the self-boosting standard voltage transformer is connected with a high-voltage nuclear phase instrument to be detected, and the output end of the self-boosting standard voltage transformer is further connected with the feedback input end of the program-controlled standard voltage source.
2. The high-voltage nuclear phase instrument calibration device according to claim 1, characterized in that: the calibration device further comprises a linear power supply which is respectively connected with the power amplifier in each detection channel.
3. The high-voltage nuclear phase instrument calibration device according to claim 2, characterized in that: the linear power supply adopts a ring transformer step-down rectification technology to provide a pure power supply for the power amplifier, and digital signal interference introduced by the digital power supply to the power amplifier is avoided.
4. The high-voltage nuclear phase instrument calibration device according to claim 1, characterized in that: the program-controlled standard power supply comprises a digital signal source and a PID regulating circuit;
the PID regulating circuit is used for comparing the signal generated by the digital signal source with a standard voltage feedback signal generated by a self-boosting standard transformer and automatically correcting the signal;
the digital signal source comprises an ARM micro-control processor and a synchronous processing module; the synchronous processing module comprises a CPLD chip and a DAC module; the input end of the ARM control processor is connected with the VFD keyboard, the output end of the ARM control processor is connected with the signal input end of the PID adjusting circuit sequentially through the CPLD chip and the DAC module, the feedback input end of the PID adjusting circuit is connected with the output end of the self-boosting standard voltage transformer, and the output end of the PID adjusting circuit is connected with the power amplifier.
5. The high-voltage nuclear phase instrument calibration device according to claim 4, wherein: and the synchronous processing modules of the digital signal sources in the two detection channels are connected through a synchronous signal line, so that the signal synchronization between the two detection channels is ensured.
6. A calibration method of a high-voltage nuclear phase instrument, which adopts the system of any one of claims 1 to 5, and is characterized in that: the method comprises the following steps:
s1, a user sets voltage and phase parameters needing to be output and measured through a VFD keyboard, and after the voltage and phase parameters are confirmed, the VFD keyboard transmits the parameters set by the user to a program control standard voltage source;
s2, generating a two-phase standard sinusoidal voltage signal by a digital signal source of the program-controlled voltage source according to user setting, and transmitting the two-phase standard sinusoidal voltage signal to a PID (proportion integration differentiation) regulating circuit;
s3, carrying out proportional, integral and differential processing on the standard sinusoidal voltage signal and the standard voltage feedback signal by the PID regulating circuit, and then transmitting the processed signals to a power amplifier;
s4, amplifying the weak signal to a self-boosting standard voltage transformer by the power amplifier by adopting a linear power amplification technology;
s5, the self-boosting standard voltage transformer further boosts a voltage signal to 10kV high voltage and transmits the voltage signal to a high-voltage nuclear phase instrument, meanwhile, a standard voltage feedback signal is sent back to a PID (proportion integration differentiation) regulating circuit to be precisely corrected, so that large loop feedback control of precise voltage is realized, and the output voltage is ensured to be consistent with the voltage set by a user;
and S6, recording the detection voltage amplitude and the phase parameters of the high-voltage phase checking instrument, and comparing the detection voltage amplitude and the phase parameters with the parameters set by a user to realize error calibration of the high-voltage phase checking instrument.
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Cited By (1)
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