Abstract: An electric powertrain includes an electric machine, an inverter connected to the electric machine, and an energy storage system for providing an electric current. The energy storage system includes a first energy storage device operable at a first device voltage, and a second energy storage device operable at a second device voltage. A plurality of low-loss switching devices interconnect the first energy storage device and the second energy storage device. The switching devices are selectively controllable between a first operating mode for providing the electric current at a first system voltage, and a second operating mode for providing the electric current at a second system voltage. The first system voltage is different from the second system voltage.

Abstract: A stripline RF transmission cable has a flat inner conductor surrounded by a dielectric layer that is surrounded by an outer conductor. A jacket with an attachment feature surrounds the outer conductor. The attachment feature may be a fin aligned parallel or normal to the inner conductor. The attachment feature may be continuous or periodic along a longitudinal extent of the cable. The attachment feature may include male and female portions dimensioned to couple with one another, enabling adjacent cables to be attached to one another.

Abstract: An electric motor has a control circuit that enables an operational speed of the electric motor to be selected with reference to multiple ranges of speeds and the input voltage to the motor. Switching between speed ranges occurs in response to activation of a switch or in response to expiration of a time period set by a selector switch.

Abstract: A method for controlling a rotary electrical machine and a control and power module for a rotary electrical machine. The rotary electrical machine includes a plurality of phase windings (9), a power circuit (12, 16) which comprises a plurality of arms each formed by a bridge of switches and which is capable of supplying an electrical network at an output voltage (Vres) equal to a nominal voltage when the bridge of switches is in a nominal mode of operation, an excitation winding (11) through which flows an excitation current (I exc) which generates a magnetic flux in a magnetic excitation circuit (10), and an electronic control circuit (7) which operates the power circuit and controls the excitation current. The method includes locking the bridge in at least one arm of the power circuit in a conductive state when the output voltage exceeds a voltage threshold higher than the nominal voltage. The nominal mode of operation of the bridge is returned to independently of the output voltage.

Abstract: A power tool has an electric motor with field windings. Each field winding includes two coils. When the motor is first energized, the two coils of each field winding are connected in series, reducing in-rush current. Upon expiration of a soft start period, the two coils of each field winding are connected in parallel. In another aspect, the field windings that are connected in series with a separate start winding when the motor is first energized. Upon expiration of the soft start period, the start winding is bypassed. In another aspect, the field windings are connected in series with a start impedance when the motor is first energized and a time delay relay having a set of delay contacts coupled across the start impedance energized. Upon expiration of the soft start period, the time delay contacts close, bypassing the start impedance. In an aspect, the motor is a universal motor.

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 permanent magnet motor includes salient pole stator cores. The poles and/or linking portions therebetween are wound with a plurality of winding coil sets. Mutually exclusive speed ranges are established between startup and a maximum speed at which the motor can be expected to operate. A different number of the motor stator winding coils are designated to be energized for each speed range for maximum operating efficiency. The number of energized coils are changed dynamically as the speed crosses a threshold between adjacent speed ranges.

Abstract: In a circuit arrangement for starting a DC motor comprising at least one field winding, particularly for switching on a DC motor for driving a hydraulic fluid pump for operating hydraulic actuators of a vehicle loading platform system, means are provided for switching on at least one field winding and means activatable by the switching on of the at least one field winding for fully activating and starting the DC motor.

Abstract: An integrated transmission is effectively achieved within a series-excited motor by varying the number of winding turns in the field coil in relation to the speed-torque demand on the motor. At low motor speed, all of the field winding is engaged to produce the maximum available electromagnetic field, thereby increasing the motor's available torque and efficiency. When there is a high torque demand at high speed, only a portion of the field winding is engaged so that a reduced electromagnetic field is produced, thereby allowing a higher current in the motor, thereby allowing a higher torque to be produced. Thus the series motor with integrated transmission will have the same speed-torque characteristics as a system with a series motor and a conventional transmission. The integrated transmission can be implemented with relatively inexpensive relays and, if desired, by adding additional winding turns in the series field.

Abstract: In an appliance having an a.c. series motor, which comprises a rotor coil configuration and two stator coils, switching means are provided for switching the a.c. series motor to different speeds or speed characteristics. Both coil ends of each of the two stator coils are accessible from outside of the a.c. series motor and are connected to the switching means. The switching means connects either one stator coil or both stator coils in series or both stator coils in parallel and in series with the rotor coil configuration.

Abstract: The series field winding of a compound or series motor includes a plurality of taps and, connected in parallel therewith, a transient storage element such as a capacitor, and a flywheel diode. The taps are controlled by switches in the form of transistors or thyristors which are turned on and off by a central control unit in response to setting of the speed and, optionally, various feedback devices such as a motor speed detector, an armature EMF detector, or a load current detector. The transient storage device replaces conventional linear impedance or linear power elements in order to prevent loss of power as the armature voltage is increased.

Abstract: A DC shunt or compound motor, in which an armature current detection device, provided to increase the current in the shunt field winding following an increase in armature load current, causes the motor to have characteristics similar to a series motor until a maximum setting value is reached, at which time the speed is held constant with increasing torque as is characteristic of a shunt-type motor. Below a minimum speed, the torque also increases as in a conventional shunt-type motor.

Abstract: A motor control circuit provides series or compound excitation during starting and shunt excitation during normal running. A switch responsive to the motor speed, the armature current, the armature EMF, or the like, includes terminals connected to the series winding and a series winding bypass to permit switching between a compound series and a shunt configuration. In addition, a tap may be provided on the series winding for providing intermediate characteristics, and separate switches for the series and shunt field windings may also be provided.

Abstract: A governor circuit for limiting the top speed of a universal series or compound motor. The governor circuit includes a voltage detector for detecting a selectable threshold voltage across the armature of the motor, and a current shunting circuit which is triggered by the voltage detector when the armature voltage of the motor reaches the threshold level to thereby shunt current through an auxiliary field winding and around the armature and/or main field winding, thereby limiting the speed of the motor. A plurality of embodiments is disclosed which accommodate various conventional power supply types.

Abstract: A speed control circuit in combination with an electrical motor for use in a hand-held food mixer operated on AC household electrical current. The motor is a universal type having a series connected armature winding and field winding wherein the field winding includes a plurality of taps each selectably connectable to the current source by a multipoint switch. A Quadrac.TM. semiconductor switch containing a triac and triggering diac in one package conducts electrical current from the current source through the armature winding and the selected portion of said field winding over a portion of each cycle of the current source. A trigger signal causes switching of the semiconductor switch at a predetermined phase angle relative to the voltage waveform of the current source. An error signal of a magnitude proportional to motor speed and based on counter EMF of the motor is generated by the entirety of the field winding.

Abstract: A method of controlling and a controller for controlling at least one series motor is provided. Rectifier means is connected in series with the motor so that current through a field winding of the motor is always in the same direction irrespective of the polarity of the input voltage while the current direction through an armature of the motor reverses in accordance with the polarity of the input voltage. An energizing current is applied to the field winding by a bias power supply to ensure that the field winding always produces some flux during operation of the motor.

Abstract: A pulse control circuit for a d.c. series motor having an armature and two oppositely-wound field windings, comprises two semiconductor static switching devices, such as thyristors, each connected in series with the armature and a respective one of the field windings, control means for varying the mark-to-space ratio of conduction of each switching device thereby to vary the mean voltage applied to the motor, one or other of the switching devices being brought into operation to energize the associated field winding in dependence on the desired direction of drive of the armature. The control means is adapted, when the mark-to-space ratio of one of the static switching devices has been brought to a predetermined maximum value, to cause simultaneous operation of the other static switching device at a lower mark-to-space ratio thereby to energize the associated field winding so as to reduce the net flux in the motor and further increase the motor speed.

Abstract: A motor control is provided for a DC series motor operative with a chopper apparatus and including a thyristor switch to determine the field shunt operation of the motor. A voltage reversal that occurs across the field windings when the chopper is OFF and not conducting is utilized to commutate and enable modulation of the field shunt thyristor switch as desired in relation to the chopper ON and OFF operation.

Abstract: A field shunt operation for a chopper controlled series DC propulsion motor in the power mode is provided in response to a desired torque request, when a predicted value of the resulting shunt field motor current is determined to be no greater than the known commutation current limit of the chopper.

Abstract: A drive circuit for a DC motor provided with an armature having an armature winding and a plurality of field poles. The field poles are each composed of a main pole excited by a field winding and an auxiliary pole formed with a permanent magnet of the same polarity as the main pole. An armature current is shunted to supply a field current to the field winding connected in series to the armature. The field current remains zero until the armature current reaches a predetermined value, and increases with an increase in the armature current after the latter exceeds the predetermined value. As a result of this, in the region in which the armature current is small, that is, in the high-speed region of the motor, a torque larger than that of a DC series motor is obtained, and in the region in which the armature current is large, that is, in the low-speed region of the motor, a torque larger than that of a permanent magnet type DC motor is provided.

Abstract: A switch for speed control of an electric motor driven vehicle employs a combination of resistance switching, field weakening and voltage switching. A mechanical switch assembly has a speed switch and a voltage switch that are interconnected so that the voltage switch provides 36 volts when the speed switch is in neutral and fifth speed position and provides 18 volts when the speed switch is in first through fourth speed positions. The speed switch has an operator controlled rotor arm that successively engages a neutral contact and five driving speed contacts so that varying resistance is inserted in circuit with the motor armature in the first two speed positions and no external resistance is employed in the third and fifth speed positions. The motor field comprises pairs of first and second oppositely disposed series wound coils with the pairs of coils all connected and energized in series in all but the fourth speed position.