Space vector pulse width modulation (SVPWM) on DSP platform for utility grid synchronizable tie-line converter between AC-bus and DC-bus of a microgrid

(College of Engineering, Pune) COEP-MICROGRID, project by the students of COEP, Pune aims at establishing a microgrid in the college campus. Proposed microgrid has a AC-bus and DC-bus, interconnected together with a tie line DC-AC converter. AC-bus is connected to wind power plants, pico-hydro plant, STATCOM, local AC-loads. In order to maintain required power quality, a low THD on the AC bus side is required. Space vector pulse width modulation (SVPWM) technique is used to drive 2-level voltage source inverter. Microgrid has intermittent generation on DC BUS. Control strategies are so designed as to regulate power and maintain the demand supply balance between DC BUS and AC BUS. To start with, we discuss the basic philosophy of SVPWM and also the design and implementation of its algorithm on a Digital Signal Processor for its generation. The basic architecture of the PWM modules of the DSP is explained and the specific use of the registers in those modules to generate SVPWM is elaborated. The inverter is simulated with the existing architecture of COEP-microgrid and its response in various microgrid scenarios is discussed. This paper also describes implementation of the designed inverter and the corresponding results.