Relay is a kind of switching device working in the control loop, which is usually used in the control circuit. It has the characteristics of high power through, high reliability of physical isolation, and low influence of environment on switching characteristics. Benefiting from the intelligent and energy-saving oriented electrification process, electronic switches replace mechanical switches, which are widely used in household appliances, electric power, automobiles, industrial control, communications and other aspects. It improves the automation level of control through the form of electrical signal triggering. From the trend, the number of relays used by a single device will continue to grow. According to the research report released by the international market research institute MarketsandMarkets, driven by the increased investment demand for distribution automation, the global relay market will reach 1.033 billion US dollars by 2021, with a compound annual growth rate of 3.9%. The report believes that the increase in energy demand promotes the market to improve the quality of power supply requirements So as to promote the steady growth of the market demand for automotive relays. Regionally, North America will be the largest automotive relay demand market in the world, followed by Asia Pacific and Europe. From a single country point of view, the United States will become the largest single market country in the world, followed by China and India, due to intensive power infrastructure upgrades and large-scale deployment of distribution automation projects. The report also warns that insufficient government investment to improve grid stability, high relay costs and disorderly market competition will be constraints to the development of the market. At present, the global automotive relay market is too decentralized and not highly concentrated. Only a few enterprise giants continue to explore the international market through mergers and acquisitions