摘要 |
The inverter includes a low voltage microcontroller referenced to ground potential and a waveform generator coupled to the microcontroller through a serial data link including optical isolation devices. The waveform generator floats at the negative bus potential of the DC source for the inverter. The waveform generator produces switching signals for the inverter under control of the microcomputer. The waveform generator, serial communications circuitry and other support circuits are all part of a single application specific integrated circuit. Registers store control parameters from the microcontroller, and counters, a look up table and a state machine derive pulse width modulated switching commands to achieve motor control for a 60.degree. sector of motor field rotation and repeat the derivation of similar switching commands for each subsequent sector. A pulse director applies the pulses to the correct motor phases for a given sector.
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