Analysis Of Anti Short Circuit Performance Of Magnetic Holding Relay And Research On Its Test System

Recently,with the increase of residential electricity consumption,stability and efficiency have become the goal of smart grid transformation,and the construction of smart grid has promoted the popularization of smart meters.Against the background that countries around the world have successively launched power grid transformation projects,the market demand for smart meters is unprecedentedly huge.Faced with technological upgrades,China,as a major power meter producer,presents both opportunities and challenges.The International Electrotechnical Commission formulated the international standard(IEC62055-31)for pre-paid smart meter testing in 2005,which aims to improve the safety and reliability of the meter.Magnetic latching relays,However,as the key internal switching elements of smart meters,require to meet the relevant test level under its standard requirements,and make sure that it has a good ability to withstand short-circuit current.The research work of the thesis takes the magnetic latching relay commonly used in smart meters as the research object.Aiming at the problems of unstable performance and high failure rate under short-circuit conditions,this papers summarizes and analyzes the relevant factors that affect its short-circuit resistance performance,then combines the problems existing in the production and daily use process,taking the driving part of the electromagnetic mechanism and the contact part of the contact as the main body of research,and using ANSYS software to analyze the influencing factors and driving force of the electromagnetic driving part.Subsequently,Based on the orthogonal experiment method,its coil Parameters such as wire turns,wire diameter and inner core length are optimized,so as to obtain the optimal parameter group of the electromagnetic drive structure.At the same time,a contact simulation analysis model was established based on the bending position of the movable conductive rod of the contact mechanism and the thermal effect of the contact surface,in order to examine its influence on the breaking performance of the contact,which provides a reference for the subsequent improvement of the short-circuit resistance of the magnetic latching relay.As the main work content,this paper designs and develops a magnetic latching relay anti-short-circuit test system that meets its UC3 level requirements based on the IEC62055-31 test standard to achieve the short-circuit current test requirements of 3k A making capacity and 3k A/6k A carrying capacity.The test system uses a synthetic test method to complete the design of the main circuit.The voltage source required for the test is adjusted by the isolation transformer and the control voltage regulator,and the short-circuit current source is generated based on the LC oscillating circuit design.Both of them work together to complete the test action.At the same time,in order to realize the intelligence of the test system and reflect the human-computer interaction during the test,this paper designs a supporting computer control and monitoring system based on the LabVIEW and DSP development environment.The communication between the upper and lower computers is based on the RS-485 protocol,So as to realize the functions of data collection,transmission processing and control actions between the two.Among them,the DSP controller of the lower computer mainly realizes the functions of signal acquisition and control actions.The main interface of the LabVIEW upper computer is responsible for sending test instructions,monitoring the status of the test process in real time,automatically saving test data,and generating electronic forms.Users can also check and analyze historical test data at any time.Finally,based on the above research foundation,the construction and testing of the physical test system were completed,which provided equipment testing methods and conditions for the development and testing of relay products.