A dynamic dynamometer for testing variable speed drives

Standard dynamometers for testing electric machines are usually only capable of simulating the static torque characteristics of various industrial loads. For machines which are mainly operating in steady state, this is satisfactory. However, for inverter-fed AC machines, the dynamic performance can also be important. This paper develops a control strategy based on local vector (LV) control, which allows a DC machine to be controlled to simulate both the static and dynamic characteristics of representative industrial loads. One particularly interesting aspect of this is that nonlinear effects in real loads, such as backlash and stiction, can be accurately simulated. The paper presents simulation results for the dynamometer and discusses the structure of the hardware being developed for the system