The losses in control electric drives of transport mechanisms at different controlled laws

Abstract

As a rule, the work of electric drives of transport mechanisms arises with variable load and with different control laws of torque and speed. That leads to redistribution of losses components and demands take it in attention. In the report, the character change of the general losses and their components are compared in different type of electric drives under change of the load. In connection with this, it is paid attention to features of redistribution of losses in the perspective for transport mechanisms electric drive with field regulated reluctance machine. This machine is characterized by increased reliability, high specific parameters, simplicity of a design and control, and opportunity work in aggressive conditions. The opportunity realization of control laws in the electric drive with reluctance machine (with independent excitation) the same as in the electric drive of direct current machine makes perspective comparison of losses in these electric drives. In the basis of the analysis lays observation that at the motors having close values of efficiency, the character of change losses components also is close though their absolute losses can differ considerably. This fact makes it possible to present the change in component losses at the change load in relative units. In this case, the bases values are taken equal to total losses in the electric motor in a nominal mode. At this, absolute losses can be different and highly significant inside each series of electric motors. The results of analysis are confirmed by laboratory measurements in electric machine stands. © 2011 SAE International.