Abstract: A method of linearizing the output performance of a switched reluctance generator, comprises the steps of exciting the switched reluctance generator during a first phase of operation at a turn-on angle which need not be accurately calculated to produce the desired excitation current. Next, during a second phase of commutation, the switched reluctance generator is freewheeled when a phase current of the switched reluctance generator exceeds a first calculated current level. This freewheeling continues until the phase current of the switched reluctance generator exceeds a second calculated current level, at which point the switched reluctance generator enters the generation phase of its commutation cycle. The linearization of the performance occurs because the first and second calculated current levels are calculated as a function of energy converted per electrical cycle.

Abstract: A method of commutation of a switched reluctance machine to allow operation in a generate mode comprises the steps of closing upper and lower switches coupling a stator winding to a power bus during an increase in the inductance of a stator winding to allow a flow of current from the power bus through the winding, opening one of the upper and lower switches when the current reaches a first predetermined value, opening the closed of the upper and lower switches during a decrease in the inductance of a stator winding, and closing one of the upper and lower switches during a period of non-alignment of the rotor and stator pole. The method further includes the step of closing both the upper and lower switches if the monitored current falls below a second predetermined value. In this way, the current through the stator winding is not allowed to decay to zero.

Abstract: The present invention provides for detecting rotor speed through the use of sense coils on the stator teeth. Voltage ripples caused by the rotor slots is detected by combining the signals of several such sense coils so that the fundamental voltage signal is cancelled or rejected and only the ripple voltages remain, a signal proportional to rotor speed. Several alternative methods for implementing that technique are discussed herein. At low induction motor speeds, the present invention filters out the voltage ripples and incident third harmonics and instead estimates rotor speed from the fundamental voltage. When the induction motor is already being driven by a prime mover, the present invention selects a proper initial frequency command for initial motor start by identifying rotor speed from the PWM inverter. Further, the present invention provides for using a generator to control voltage to the induction motor, with a PWM inverter to control frequency signals to the induction motor.

Abstract: An electric power generating system comprises a switched reluctance machine, an inverter having a dc input/output coupled to a dc bus, switches responsive to switching control signals for coupling each of the machine's phase windings to the dc bus, and diodes for cross-coupling each of the phase windings to the dc bus. A controller having a number of control inputs and outputs coupled to the inverter monitors the current flowing in the phase windings and the voltage level on the dc bus, and calculates a maximum and a minimum phase current control signal. The controller modulates the switching control signals to regulate the phase current within a range defined by these control signals to maintain the voltage level at a desired level. Upon calculating a positive phase current control signal, the controller generates switching control signals to enable switches at a fixed angle prior to alignment, and generates switching control signals to disable the switches at a fixed angle after alignment.