A dead-beat adaptive hysteresis current control

This paper proposes a new digital algorithm for the implementation of the f ixed-frequency adaptive hysteresis current control for voltage-source inver ters. The key features of the new algorithm are the minimization of the ana log external circuitry, the capability to automatically compensate for the inverter deadtime effects without appreciable delay and a tight synchroniza tion of the inverter voltage pulses with an external clock. The synchroniza tion is actually inherent in the implemented algorithm and does not require additional control loops; the stability problems affecting all the solutio ns proposed so far are, therefore, avoided and a steady switching frequency is achieved. Even though the complexity of the algorithm is compatible wit h many conventional microcontrollers' performance level, the implementation with a commercial digital signal processor is considered in order to achie ve ultrasonic operating frequency and to test the effectiveness of the solu tion in more demanding conditions.