在大型的农用设备或加工生产线中,经常要使用大功率的异步电动机,这种电动机在正常运行时,三相绕组一般采用三角形接法。为避免启动时过大的电流对公共电网系统的影响,绕组往往采用“星—三角”接法启动,其典型电路见图1。 In large-scale agricultural equipment or processing production lines, often use high-power induction motor, this motor in normal operation, the three-phase winding is generally used to connect the triangle. In order to avoid the impact of excessive current on the system of public power grid at start-up, the windings are usually started by the “star-delta” connection method, and the typical circuit is shown in FIG. 1.