Results of the development and testing of traction electrical equipment of mining dump truck with load capacity of 240 tons

Abstract

Basic results of development of an ac electromechanical transmission for the BelAZ mining dump truck with a load capacity of 240 t carried out at Ruselprom have been considered. The requirements and features have been studied of traction electrical equipment that complicate the solved task, in particular the limited response speed of voltage control channel in a dc link, low capacity of the link, the range of control of variables with a field reduction of more than 15: 1, and required braking regime power twice exceeding the traction regime power. A functional diagram of traction electrical equipment is shown, and the frequency-dependent temperature derating of the extreme output current of the inverter to improve the reliability and maximum use of power keys is considered. The structures of control systems that work via excitation of a synchronous traction generator and by the left and right wheel drives and model of the dump truck have been described. As a result of modeling the dynamic characteristics and operating regimes of an internal combustion engine, generator and traction motors have been brought into coincidence, the most effective version of control algorithms in a slipping of the driving wheels has been selected, and the low sensitivity of electrical drives to the change of parameters of the power channel has been found. The program, the technique, and the results of tests of traction electrical equipment on a full-scale test bench have been presented. The required static indicators have been achieved, as well as the time of processing of the step rise of generator nominal load equal to 0.2 s with a voltage depression of 5% and a transition from the extreme traction torque to 90% of the brake torque of less than 2 s in any working speed. Ground tests of a dump truck with the designed set of equipment are planned for the first half of 2015.