Abstract: A cart may include a driving wheel, a motor configured to rotate the driving wheel, a motor drive circuit configured to drive the motor, a motor brake circuit configured to electrically brake the motor, a control device configured to control the motor via the motor drive circuit and the motor brake circuit so that a travelling speed of the cart becomes equal to or lower than an upper limit travelling speed, and a temperature sensor configured to detect a temperature of the motor brake circuit. The control device may be configured to change the upper limit travelling speed to a second upper limit travelling speed lower than the first upper limit travelling speed when the upper limit travelling speed is a first upper limit travelling speed and the temperature detected by the temperature sensor exceeds a first predetermined temperature.

Abstract: A system for controlling a trapezoidally (square wave) driven DC motor includes a unipolar commutation circuit coupled between a DC power supply and a brushless DC motor. The motor has three phases formed by respective stator windings coupled at respective proximal ends to a common node and having respective opposite ends remote from the common node. The commutation circuit drives the motor according to a commutation cycle including three primary steps. During each primary step, one of the phases is driven while the other two phases are not driven. Voltages at the remote ends of the undriven phases are sensed, and timing signals are generated at points where the voltages coincide. The timing signals are used to determine motor position and speed, and to synchronize the commutation cycle with motor position and speed. In one embodiment, the commutation cycle includes transitional steps between the primary steps for smoother operation.

Abstract: A commutator motor, which has a series excitation or shunt excitation and which, in particular, is suited for use as a drive motor for a washing drum of a laundry treatment device. The stator of a commutator motor of this type has a number of field winding groups with field windings that are arranged symmetric to the plane of symmetry of the pair of poles and whose starting points and end points are connected to one another. In order to operate the commutator motor in a number of rotational speed ranges, the field winding groups are individually or jointly activated by a control device.

Abstract: A field-adjustable motor control system includes a motor, an inverter coupled to provide energization to the motor, a controller coupled to the inverter, and a field adjustment circuit that provides field adjustment signals to the controller. The controller provides signals to control the output of the inverter in response to received input control signals and field adjustment signals. The input control signals define the controller's operating state that corresponds to a desired system operating state. The field adjustment signals and input control signals define a desired output parameter of the inverter for an operating state. In certain embodiments, fail-safe circuitry is also provided that includes a relay receiving controller signals. The relay's input is coupled to a line power and to the inverter output. The relay's output is coupled to the motor. If the controller fails, the relay couples the line power to the motor.

Abstract: A permanent magnet DC brushless motor control assembly permits a user to select the permanent magnet DC brushless motor operating characteristics by selecting appropriate control circuits to interface with the motor. The assembly includes a permanent magnet DC brushless motor, a commutator electrically coupled to the motor, and at least one control module electrically coupled to the commutator, to control operating characteristics of the permanent magnet DC brushless motor.

Abstract: A method of starting a brushless DC motor 12 at any initial speed (A) establishes a initial stator-field speed and setting a counter of synchronization, (B) measures a speed of a rotor of the motor, (C) compares the speed of the rotor with the stator-field speed to determine if the rotor is synchronized with the stator-field. If the rotor is not synchronized with the stator-field, the method includes (a) re-setting the counter of synchronization, (b) increasing an acceleration portion of motor current (Iacc) to enhance torque, (c) setting the stator-field speed higher than the rotor speed, (d) calculating a period of an open-loop timer, (e) calculating a value for a load portion of the motor current (Ild), where total motor current I=Iacc+Ild, (f) performing commutation based on the open-loop timer and returning to step (B) until the rotor is synchronized with the stator-field.

Abstract: A system is provided for controlling a DC motor which is constructed to propel a golf car. The motor is a shunt wound motor having independently excited armature and field windings. The basic input to the armature of the motor is supplied through a pulse modulated chopper circuit which varies the width of the pulse in response to the throttle of the golf car. Full control of the input to the field winding is gained by the supply of power to an H bridge circuit. Armature current is continuously sensed to provide an indication of the status and performance of the car during operation. At a predetermined level of armature current the field current is adjusted to provide a higher torque at a specific speed. When armature current indicates a predetermined overspeed condition, field current is adjusted to enhance regeneration and the resultant braking. In addition, the stopped condition is continuously monitored.

Abstract: A system is provided for controlling a D-C motor which is constructed to propel a golf car. The motor is controlled to provide performance according to a predetermined field current map which calls for a particular performance response to specified performance events. The performance events are detected by sensing actual speed and armature current and the performance response is triggered by adjustment of the field current. A performance map correlating actual speed to various events and specifying the field current response is designed for the motor used. In addition an armature current performance map is similarly constructed correlating armature current to particular performance events.

Abstract: An electric motor control for a series-wound DC motor for providing speed control and also for controlling regenerative braking. The regenerative braking is energized either when the accelerator pedal is released and/or when a brake pedal is depressed. In addition, the control circuit limits the total vehicle speed and brakes the vehicle if it is stopped and begins to roll due to gravity.

Abstract: A system is provided for controlling a DC motor which is constructed to propel a golf car. The motor is a shunt wound motor having independently excited armature and field windings. The basic input to the armature of the motor is supplied through a pulse modulated chopper circuit which varies the width of the pulse in response to the throttle of the golf car. Full control of the input to the field winding is gained by the supply of power to an H bridge circuit. Armature current is continuously sensed to provide an indication of the status and performance of the car during operation. At a predetermined level of armature current the field current is adjusted to provide a higher torque at a specific speed. When armature current indicates a predetermined overspeed condition, field current is adjusted to enhance regeneration and the resultant braking. In addition, the stopped condition is continuously monitored.

Abstract: A dc motor wherein a driving force thereof can be used effectively with a simple and compact mechanical construction and a motor controlling system which can control such a dc motor to be driven efficiently. The motor comprises at least two coils, and change-over means for changing electric connection of the coils to change over the motor, when power is selectively supplied to the coils, between a first mode in which the torque produced is relatively high and the rotational frequency is relatively low and a second mode in which the torque is relatively low and the rotational frequency is relatively high. The motor controlling system includes selecting means for automatically selecting one of the first and second modes to control the change-over means in response to a given condition of the motor.