Abstract: A motor control system is provided comprising an electrically charged battery, an electrical motor, a battery voltage sensor, a motor speed sensor, an armature voltage sensor, an armature current sensor, and a microprocessor. The magnitude of the armature current applied to the motor is a function of a predetermined armature current setpoint signal and the magnitude of the field current applied to the motor is a function of a predetermined field current setpoint signal, a field current correction signal, and a field current de-boost signal. The microprocessor programmed to generate an armature current setpoint signal, a field current setpoint signal, and an armature voltage reference signal.

Abstract: Optimal constructions for two motor/controller configurations are disclosed. The controller structure includes an H-bridge for controlling field current using synchronous-rectification of MOSFET devices, and a circuit for chopping the armature current using synchronous-rectification of MOSFET devices arranged in a half bridge. The controller may be configured with a series-wound or a separately excited DC traction motor. In the series-wound motor/controller configuration, the field and the armature current are separately controlled. In the separately excited motor/controller configuration, the field of the motor is preferably wound so that the rated field current is achieved at about 20% of the rated battery voltage. This provides a separately excited motor in which the field current can be boosted by a factor of 5 to achieve high start-up and low speed torques which match the torque outputs of a series-wound motor under similar operating conditions.

Abstract: A MOSFET control topology and a physical structure for a motor control which provide a more efficient and economic DC motor control are disclosed. The control topology introduces a synchronous-rectification technique wherein free-wheel diodes are replaced with MOSFET devices that are switched on and off by a logic circuit so that they are conductive for commuting motor current during periods that the motor current supply is switched off. The physical structure and method of assembling a DC motor control eliminate time consuming assembly techniques while ensuring effective waste heat exchange between electronic components and a heat sink of the control by providing quick-install spring retainers for urging the components into heat sink conducting contact with the heat sink. The physical structure also provides for high density packing of electronic components in a controller.