| Abstract |
An operating analysis and simulation of a surface mounted permanent magnet synchronous machine fed by a 120° hysteresis current controlled power MOS-FET inverter is proposed. The Hysteresis-band current control technique is widely used because of its simplicity of implementation, fast current loop and inherent peak current limiting capability. In spite of this, a systematic analysis of the commutation phenomena in this kind of current control is not easily found in the literature when used in a 120° inverter with current measured in the DC section. Other schemes using hysteresis and PWM techniques on 180° inverters are found. The paper is mainly directed to the establishement of general equations that describe all possible configurations of the whole circuit. Special emphasis is given to the possibility of action of the hysteresis current comparator during the phase commutation an to the possibility of conduction of the open-circuited phase diodes. General equations are written that take into account the hysteresis comparator status. These equations demonstrate, among other things, that the decreasing current does not depends on this status. A simulation program was written that includes the mains rectifier, filtering RC, inverter, machine and command. This simulation is done by operating sequences taking, however, into account the hysteresis comparator and the rotor sensors signals. |
