Electric Power Components and Systems, 30:863–875, 2002 Copyright c ® 2002 Taylor & Francis 1532-5008/ 02 $12.00 + .00 DOI: 10.1080/ 15325000290085073 Sliding Mode Control of a Mechanical Speed Sensorless dc Motor Drive Fed from a Current Controlled Chopper BHIM SINGH Department of Electrical Engineering Indian Institute of Technology Delhi , New Delhi-110 016 , India J. R. P. GUPTA Department of Instrumentation and Control Engineering Netaji Subhash Institute of Technology New Delhi , India BRIJ N. SINGH Department of Electrical Engineering and Computer Science Tulane University , New Orleans , LA 70118 , USA C. L. PUTTASWAMY Department of Electrical Engineering Indian Institute of Technology Delhi , New Delhi-110 016 , India SANJEET GUPTA National Thermal Power Corporation Limited NOIDA (U . P . ) , India B. P. SINGH Department of Electrical Engineering Indian Institute of Technology Delhi , New Delhi , India Manuscript received in nal form on 13 September 2001. Address correspondence to Dr. Brij N. Singh. 863