Abstract:

The Soviet electric shovel EKG-8I with Ward Leonard drive systems are still widely used at the openpit coal mines and play an importance role in Vietnam mining industry. In order to improve the quality of their control, instead of a magnetic amplifier, an IGBT DC-DC converter was suggested to control the generator excitation field and a controller with an electro-shovel characteristic structure was proposed for the EKG-8I drive system. The simulation results show that thanks for these suggestions, system is able to control and maintain stable operation when encountering hard rock loads.