The application of multistage invariable permanent current source in magnetic force adjustment

Traditional magnetic crane in the actual operation due to the saturation of the electromagnet coil excitation is prone to produce excessive current and causes the waste of energy. In the demagnetization stage, Stored energy through the electromagnet coil braking resistance heat release, no feedback to the power grid, has also caused a lot of waste. Another electromagnet is a big inductive load. When DC contactors are connected or disconnected, inductance back electromotive force is very large, and very prone to generate arc light, and burn out DC contactor, so the failure rate is very high, and maintenance ia also a very heavy workload. For the traditional magnetic crane appears a variety of issues in the actual operation, we start this article with the magnetic circuit of magnetic lifting magnet, Which analyses and research the process of magnetic crane excitation and demagnetization further, and puts forward a multi-level variable constant current source magnetic-conditioning scheme. The scheme takes control of the exciting current, and makes the upfield of the magnetic Crane magnetize fast, demagnetization fast, less energy consumption, improve the steel loading speed, and improve the safety coefficient of magnetic crane by using the PLC programming and fully controlling bridge circuit.