The Opening Speed Detection Of Vacuum Switch Based On LabVIEW

As a control and protection device for power systems,the vacuum switches have the advantages of long service life,no pollution,convenient maintenance and compact structure.With the development of the vacuum switches in the direction of high voltage and high current,the power system has put forward higher requirements for the breaking performance of the vacuum switches.The vacuum switch is mainly composed of a vacuum interrupter and an operating mechanism.In the working process,if the power system fails,whether the operating mechanism can make a reliable action in a timely manner is the key to whether the vacuum switch can complete the breaking action.Therefore,the motion parameters of the operating mechanism are the key research topics in the field of vacuum switches.Therefore,the motion parameters of the operating mechanism are the key research topics in the field of vacuum switches.As one of the motion parameters of the operating mechanism,the opening speed has an important influence on the reliable operation of the operating mechanism and the working performance of the vacuum switches.Based on this,a vacuum switch opening speed detection technology based on LabVIEW virtual instrument development platform is proposed,which lays a foundation for further research on the working performance of vacuum switch.In this paper,a set of experimental circuit and control system for vacuum switch opening and closing test was designed.The experimental circuit mainly used an LC(capacitor-inductor)oscillation circuit as a power source to charge and discharge the capacitor.After the capacitor had been charged,the branching and closing coils of the operating mechanism were discharged,and the opening and closing operations of the mechanism can be operated.The control system of the experimental circuit adopts the combination of relay control and PLC control,which not only can successfully control the smooth operation of the experimental circuit,but also ensure the transient response of the experimental circuit.After successfully building the vacuum switch experimental platform,A CMOS high-speed camera and LabVIEW image processing technology were used to collect and process the vacuum arc images in this paper.First,a high-speed camera was used to capture the arc images of the vacuum switch for one opening cycle(about 10 ms).Then the arc image were transmitted to the LabVIEW image processing platform for noise reduction,filtering,edge segmentation,edge processing,and the like.Finally,the gap distance between the vacuum switch and the static contact at different times were calculated to calculate the opening speed of the vacuum switch.Finally,in order to verify the accuracy of the measurement results of this experimental method,in this paper,the experiment of measuring the switching speed of the vacuum switch in multiple ways were performed under the same operating conditions.Among them,based on the detection data of the intelligent switch mechanical characteristic tester,the traditional displacement sensor-based opening speed detection results are compared with the experimental results obtained by the method proposed in this paper.The vacuum switches opening detection method studied in this paper is aim to improve the reliability of the vacuum switches opening and closing action and realize the control and protection of the vacuum switches.The relevant experimental results calculation and accuracy test is completed in this paper,and provides technical support for further research on how to improve the operating reliability of the operating mechanism and the vacuum switches.