Control law and compensations of a Voltage Active Load for automotive applications

In this paper, the synthesis, the modelisation and the compensation a Voltage Active Load is presented. The main goal of these Active Loads is the emulation of electrical bodies such as electrical machines or batteries, under real power conditions. The main difficulty of this application is the needed accuracy on the emulated output signals. To respect these hard conditions, a sliding mode synthesis and a recent switching frequency limitation process are used and presented in this paper. A linear equivalent model is then proposed and makes it possible, by its inversion, to easily compensate the imperfections of the controller. Experimental results are presented and show the good operation of these Active Loads which make it possible to follow reference signals until 1500 Hz, with an error lower than 5 % on the amplitude and 5 degrees on dephasing. These good results allow actually the use of these Active Loads in industrial automotive companies.