Silicon controlled frequency conversion equipment is a frequency conversion equipment which uses the silicon controlled rectifier to converse the three phase regulated industrial frequency current in 50 weeks into intermediate and high frequency current with frequency of 300 HZ-8000 HZ. The operating principle is that the regulated industrial frequency alternating current of 50 weeks per second is rectified into direct current through a three-phase bridge rectification circuit, filtered by a filter, and finally the direct current is changed into the alternating current with certain frequency through an inverter to supply power for the load. Therefore, the inverter is actually an alternating current - direct current - alternating current converter.