Silicon-Controlled Rectifier Positioning Control of Electric Drive Units

The control equipment described in this paper has been designed to meet industry demands for electric drive units to adjust loads in the 100-3000 lb-ft torque range with accuracies comparable to those now possible for loads of up to 75 lb-ft. These demands have been accompanied by the now almost standard request that the results be achieved using low-maintenance solid-state equipment. Drive units for up to 75 lb-ft, such as that shown in Fig. 1(a), can be positioned to ± 0.25 percent or better.