Research On PWM Speed Regulating Device Of Mine-used Electric Locomotives

Aiming at there shortcomings of the two speed regulating methods, switch-in-resisters-regulation and DC pulse-width-ragulation using SCR, which are currently used in mine-used electric locomotives powered by accumulators, a speed regulating method adopting a new type intelligent power module (IPM) as a chopper is designed in this research. Not only this method overcame the disadvantage of discrete speeds of switch-in-resisters-regulation, enlarged the frequency of chopping, enabled the continuous speed regulating and decreased the power consumption, but also it improved the system performance due to the double-loop feedback PI regulation of current and speed.This dissertation expatiates on the working principle of chopping speed-regulating in mine-used electric locomotives powered by accumulators, presents the topological structure of the primary circuit of the system and its principle. The traction characteristic and the brake characteristic of the motor are obtained and the parameters of the primary circuit are given. The intelligent power module is adopted to replace the old-typed SCR. The chop frequency reaches to 2KHZ. Profiting from the greatly simplified hardware with the integrated driving and the various protections, the system performance is improved and the control is convenient. The special chip 87C196MC made by INTEL company is used as a controller in the design. It realized the control function of the system and it can meet the needs of real time control.Finally a simulation module is set up and the system is simulated with matlab. The simulation result indicates that the effect of design system is perfect. The designed system runs reliably in the lab, which make sure that the design is feasible.Figure [54] table [2] reference [40]...