The invention relates to a zero-flux current sensor, which comprises a magnetic probe winding, a signal processing circuit, a compensating current power driving circuit, an abnormity monitoring circuit, a regulating switch and a negative feedback regulating circuit. The signal processing circuit is in electrical connection with the magnetic probe winding; the compensating current power driving circuit is electrically connected with an output end of the signal processing circuit and the magnetic probe winding; the abnormity monitoring circuit is in electrical connection with the magnetic probewinding; the regulating switch is in electrical connection with the signal processing circuit; the negative feedback regulating circuit is electrically connected with an output end of the abnormity monitoring circuit and the regulating switch and is used for controlling on-off states of the regulating switch according to operating states, acquired by abnormity monitoring circuit in detection, of the magnetic probe winding to further control output signal reverse of the signal processing circuit to realize compensating current reverse, a magnetic core of the magnetic probe winding quits a saturated state when tested current recovers to a measuring range, a current measuring function is recovered, and the zero-flux current sensor recovers to a normal operating state.

Zero-flux current sensor

The invention discloses a wide-frequency-range transient space electric field measuring system and method. The system comprises a dual-plate electrode sensor, a front-end signal processing unit, a signal collecting recording unit and a transmission unit; the dual-plate electrode sensor is arranged in a transient space electric field for sensing, transient space electric field signals are convertedinto measurable voltage signals; the front-end signal processing unit is used for processing and controlling the measurable voltage signals input by the sensor and optimizing waveforms of the outputvoltage signals; the signal collecting recording unit is used for collecting and recording voltage signals output by the front-end signal processing unit, and obtaining transient electric field signals through calculation of the collected voltage signals; the transmission unit is used for transmitting the voltage signals converted by the front-end signal processing unit to the signal collecting recording unit to achieve remote measurement; according to the system and method, the differential operation function does not need to be enabled, and therefore the lower limit of the measurable electric field frequency is widened.

Wide-frequency-range transient space electric field measuring system and method

The invention discloses a spatial electric field instantaneous measuring system for surface dielectric barrier discharge. The measuring system comprises a laser unit, an SDBD excitation device, an optical path unit, a signal acquisition unit, a signal processing unit and a microprocessor. A first laser signal which is emitted from the laser unit is transmitted into the SDBD excitation device. TheSDBD excitation device generates a second laser signal and transmits the second laser signal to the optical path unit. The optical path unit performs light screening processing on the second laser signal and outputs a first optical signal. The signal acquisition unit acquires the first optical signal and generates a first acquisition signal. The signal processing unit converts the first acquisition signal to a first voltage signal, and transmits the first voltage signal to the microprocessor. The microprocessor calculates a surface dielectric instantaneous electric field according to a calibrated voltage signal and the first voltage signal. Through the measuring system of the invention, frequency-doubled light can be generated according to a secondary harmonic effect, and a transient electric field can be obtained according to a ratio between the voltage signal which is converted from the frequency-doubled optical signal and the calibrated signal. Furthermore the spatial electric fieldinstantaneous measuring system has advantages of high sensitivity and high response speed.

Spatial electric field instantaneous measuring system for surface dielectric barrier discharge

The invention discloses a system and a method for measuring a transient space electric field. The system comprises a double-plate electrode sensor used for sensing a transient space electric field to generate a pair of displacement currents with same amplitude and opposite phases, an impedance converter used for converting the displacement currents into two low-impedance voltage signals, a balance-unbalance converter used for carrying out signal differential on the two low-impedance voltage signals and outputting the low-impedance voltage signals after differential, and an oscilloscope used for collecting and recording the low-impedance voltage signals after differential. According to the technical scheme of the invention, through the impedance converter, the impedance connected to the double-plate electrode sensor approaches infinity, and the low-frequency output electrical signals have a linear relationship with the measured electric field; a transient space electric field can be measured accurately without signal integral; and by introducing the balance-unbalance converter, differential of the input signals is realized, the common-mode rejection ratio is increased, and the problem of common-mode disturbance in measurement of a transient space electric field is solved.

System and method for measuring transient space electric field

The present invention discloses a system for measurement of a transient state ground electric field. The system comprises: a plate electrode sensor configured to induct the transient state ground electric field to generate the displacement current, wherein the displacement current flows a plate electrode capacitor and a parallel impedance transformer to input impedance to form high-impedance voltage signals; an impedance transformer configured to convert the high-impedance voltage signals to low-impedance voltage signals for outputting, wherein the low-impedance voltage signals are outputted to an oscilloscope; and the oscilloscope configured to perform collection and recording of the voltage signals. According to the technical scheme, through the impedance transformer, the system and method for measurement of the transient state ground electric field can allow the shunt impedance of the plate electrode capacitor to tend to be infinity so as to greatly increase the discharge time constant of the capacitor, extend the low-frequency bandwidth of the measurement system, allow the low-frequency stage output voltage signals and the measured electric field to be a linear relation and realize the accurate measurement of the broadband ground electric field.

System and method for measurement of transient state ground electric field

The invention provides a measuring system and method of transient state electric current formed by GIS disconnecting switch operation. The system comprises a first detection device, a second detection device, an oscilloscope and a controller, wherein the first detection device detects and outputs a first transient state electric current signal which is less than or equal to preset frequency of a GIS busbar; the second detection device detects and outputs a second transient state electric current signal which is larger than the preset frequency of the GIS busbar; the oscilloscope is electrically connected to the first detection device and the second detection device and is used for outputting a first wave signal and a second wave signal; the controller is electrically connected to the output end of the oscilloscope and is used for determining the transient state electric current of the GIS busbar according to the first wave signal and the second wave signal. According to the measuring system and method of the transient state electric current formed by the GIS disconnecting switch operation, the first detection device is utilized to detect the transient state electric current with low frequency, the second detection device is utilized to detect the transient state electric current with high frequency, the transient state electric current of the GIS busbar is determined according to a full spectrum band response, and the accuracy of a detecting result is guaranteed.

Cheng Huiqing

Papers

System and method for measuring transient space electric field

System and method for measurement of transient state ground electric field

Measuring system and method of transient state electric current formed by GIS disconnecting switch operation