| 摘要 |
PURPOSE:To simplify circuit constitution of a polyphase inverter by a method wherein outputs of a sine wave generator and a triangular wave generator are compared to be modulated, and output thereof is supplied to continuously connected three shift registors to obtain control signals having respectively delay of 120 deg. of phase. CONSTITUTION:Output of the sine wave generator 11 and the triangular wave generator 12 are compared to be modulated in a comparator 14, and output thereof is supplied to the continuously connected shift registors 15, 16, 17. A signal of a clock signal generator 13 is inputted to the shift registors 15-17 as the synchronizing signal, and outputs of the respective shift registors 15-17 are made as the control signals to control conduction of semiconductor switches in respective arms of the three phase inverter. Accordingly by setting previously frequency of the clock signal and the number of bits of the respective shift registors 15-17, the three phase control signals having respectively delay of 120 deg. of phase can be obtained, and circuit constitution can be simplified reducing the number of the sine wave generator and the triangular wave generator, etc. |
