ADAPTIVE SYNCHRONIZATION CONTROL METHOD FOR PARALLEL THREE-PHASE ALTERNATING-CURRENT CONTACTOR

摘要

Disclosed is an adaptive synchronization control method for a parallel three-phase alternating-current contactor. The method comprises the following steps: step S1: testing a coil voltage of each contactor, and determining whether the power supply of a control loop is normal; step S2: when a power-on range is reached, entering a closing process, and opening a contact voltage sampling channel to test a contact voltage phase of each contactor; step S3: performing synchronization control on the closing process, considering a voltage phase change caused by a closing sequence, and finally, making a contactor in each phase be able to close synchronously in a selected phase; step S4: when it is determined through the coil voltage testing that the power supply of the control loop is in a power-off range, entering an opening process, and performing dynamic adjustment on a breaking sequence of contactors of various branches that are connected in parallel in each phase; step S5: software delay cooperating with an inherent breaking time of a mechanism to set an opening instruction; and step S6: adding an adaptive dynamic adjustment strategy to a zero-current opening control and synchronous breaking control process of the contactor. The method can realize the synchronization of an on-off process of a parallel three-phase alternating-current contactor.