Abstract: The invention relates to a method for detecting an overload in an electric hand tool (10) comprising an electric motor (12), in particular a battery-driven electric hand tool (10). According to the invention, an operating current (iB) of the electric motor (12) is determined, the difference (ID) between the value of the operating current (IB) and at least one stored current value (IG) is determined and a thermal overload of the electric hand tool (10) is deduced from said difference (ID). The invention also relates to a corresponding monitoring device (22).

Abstract: A voltage protecting apparatus is used for detecting voltage of a motor driver, and adjusting the voltage of the motor driver when at an over-voltage state. The motor driver includes a direct current (DC) power source and a power board. The voltage protecting apparatus includes a switch unit, a voltage transform unit, a controller, a voltage detector, and an over-voltage judger. When the controller outputs a high level signal, the switch unit is turned on, the voltage transform unit transforms the output voltage of the DC power source to a low voltage. The over-voltage judger receives the low voltage and compares the low voltage to a predetermined voltage. When the low voltage is greater than the predetermined voltage, the over-voltage judger outputs a control signal to the controller for signaling the controller to control the power board so as to adjust the voltage of the motor driver.

Abstract: When an electric vehicle outputs a torque instruction, firstly, a request torque is acquired and a judged whether the acquired request torque is positive or negative (S10) Regardless of the sign of the request torque, it is judged whether the eco-switch is ON (S12, S14) If the request torque has a positive sign and the eco-switch is OFF, a map A is selected (S20). If the eco-switch is ON, a map B which limits the maximum torque to a low value for the map A is selected (S22). If the request torque has a negative sign, a map C is selected regardless of the eco-switch ON/OFF state and the maximum torque is not limited (S24).

Abstract: The present invention relates generally to regenerative braking methods for a hybrid vehicle such as a hybrid locomotive, which are compatible with optimum management of a large battery pack energy storage system. Four methods for recovering energy from regenerative braking and for transferring this energy to an energy storage systems are disclosed. These methods may also be used with battery operated vehicles.

Abstract: The control apparatus for a power conversion apparatus having chopper circuits and a capacitor, each of which includes a switching circuit and a coil, the switching circuit being on/off-controlled in accordance with specific timings determined in accordance with a current flowing through the coil to create required voltage in the capacitor, includes a function of evenly dividing an interval between adjacent specific timings of one of the chopper circuits to produce divided timings to be allocated to the other chopper circuits, and a function of setting, for each of the other chopper circuits, an on-time period of the switching circuit such that, when the interval varies as a result of which the specific timing of each of the other chopper circuits deviates from a corresponding one of the divided timings, an interval between adjacent specific timings of each of the other chopper circuits is varied to reduce the deviation.

Abstract: A dynamic braking circuit for an electronic motor drive shunts the DC link of the drive with a resistor using two control strategies. The first control strategy used for lower levels of braking employs a pulse width modulated signal and the second control strategy used for higher levels of braking uses a hysteretic signal significantly reducing switching losses in the semiconductor devices controlling the dynamic braking resistor allowing higher braking capacity.

Abstract: A fluid energy machine, in particular a compressor, is provided. The fluid energy machine includes a common rotor, which is mounted using magnetic bearings, for the flow machine and the drive. In addition to the magnetic bearings, auxiliary bearings are provided, wherein a friction bearing is provided on the bottom part of the vertically oriented rotor and a roller bearing, which provides both radial and also axial mounting, and is implemented as a ball bearing, is provided on the upper end.

Abstract: A semiconductor integrated circuit for sensorless driving of a brushless motor, has: an induced voltage detecting circuit which includes a comparator for comparing a voltage induced in an exciting coil by a rotation of a rotor of the brushless motor with a midpoint voltage of the rotor of the brushless motor and outputting a detection signal corresponding to a comparison result, and detects a zero cross point where the induced voltage crosses the midpoint voltage; a logic circuit that outputs a control signal for controlling the brushless motor, in response to a command signal for regulating an operation of the brushless motor and an output signal of the comparator; and a power transistor circuit that supplies a driving current to the exciting coil.

Abstract: An induction actuated container cover includes a control housing having a cover opening, a cover panel pivotally mounted to the control housing to pivotally move between a closed position that the cover panel covers at the cover opening and an opened position that the cover panel exposes the cover opening, and an automatic driving arrangement including a sensor mounted at the control housing for detecting a target movement of a user and an actuation unit supported in the control housing to operatively link with the sensor, wherein the actuation unit is actuated to generate a decelerating and torque enhancing force to move the cover panel between the opened and closed position in a hydraulic manner.

Abstract: A motor driving circuit comprising: a synchronous rectification driving circuit to carry out synchronous rectification, to energize a driving coil connected between a first connection point at which a first source and first sink side transistors are connected in series and a second connection point at which a second source and second sink side transistors are connected in series; a backflow detecting resistor connected to electrodes of the first and second sink side transistors, the electrodes being on an opposite side of the first and second sink side transistors to the first and second connection points; a backflow detecting comparator to output a comparison signal indicating a result of comparison of voltage between a first and second terminals of the backflow detecting resistor; and a backflow prevention circuit to prohibit the synchronous rectification when the comparison signal indicates that the second terminal is higher in voltage than the first terminal.

Abstract: A system and method are provided for improved dynamic braking in AC motors with an electronic drive, and more particularly to using a current regulation circuit to control the current supplied to the motor to be in phase with the internal EMF voltage of the motor such that the braking torque of the current is maximized per ampere of dynamic braking current when needed to stop the motor in case of a control failure or emergency. A current regulator produces a voltage command to the motor based on the current command input. The motor is still controlled by a d-q current regulator and the q-axis (torque axis) voltage is driven to zero while the d-axis (non-torque axis) is left in current control with a zero current command. This way the motor internal voltage drives a current in the terminals of the motor but the current is in phase with the internal voltage of the motor.

Abstract: An electric powertrain for use with an engine and a traction device is disclosed. The electric powertrain has a DC motor/generator operable to receive at least a portion of a first mechanical output from the engine and produce a DC power output. The DC motor/generator is also operable to receive DC power and produce a second mechanical output. The electric powertrain further has a drivetrain operable to receive the DC power output and use the DC power output to drive the traction device. The drivetrain is also operable to generate DC power when the traction device is operated in a dynamic braking mode.

Abstract: A motor control circuit that features a smart, two-phase braking operation is presented. The motor control circuit includes a motor drive circuit to apply a brake current to a coil of an external motor for active braking of the motor. The motor control circuit further includes a braking control circuit, coupled to the motor drive circuit and responsive to an externally generated control signal, to control the active braking by the motor drive circuit so that the active braking occurs in two phases. The two phases include a first phase that includes a first portion of the active braking and a second phase that includes back electromotive force (BEMF) voltage sensing and a second portion of the active braking.

Abstract: A patient support device of a radiation therapy treatment system includes an electromechanical motor and control system for raising and lowering the support device in the Z direction. The control system utilizes regenerative braking concepts, converting the motor into a generator as the support device is lowered such that no matter the load, the support device will be lowered at a constant speed. The control system also allows for lowering of the support device in the powered off situation (i.e., when there is no power to the support device).

Abstract: A converter system and method, including: at least one supply module, which provides a unipolar, intermediate circuit voltage; one or more drive modules, which may be powered from the intermediate circuit voltage and each include at least one inverter for powering at least one electric motor; and at least one buffer module for storing energy.

Abstract: In a travel-driving mechanism for a self-propelled working machine such as a self-propelled lawn mower travels by using power of an electric motor 30, the torque of a driving shaft 50, which is driven by the power of the electric motor 30 through a power transmission unit 40, is transmitted to travel-driving wheels 7 through two-way or bi-directional clutches 55 provided at both ends of the driving shaft 50. Power transmission units 61, 62 are provided between the bi-directional clutch 55 and the driving wheels 7. A travel control unit 70 is provided to input an instruction signal produced by the operation of a travel operation member 66, which is operated by the operator, and to control the electric motor 30.

Abstract: A method for controlling brake resistors and a brake chopper, the number of brake resistors being two or more and the brake resistors being connected in series with switches to be controlled, the series connection being connected between a positive and a negative rail of a DC voltage intermediate circuit, the method comprising the step of determining a magnitude for a voltage of the DC intermediate circuit; and determining a first voltage limit and a second voltage limit. The method further comprises the steps of switching brake resistors to the intermediate circuit in a periodically alternating manner, each switch being switched during a switching period and the on-period of each switch in a switching period being responsive to the magnitude of the voltage in the DC voltage intermediate circuit when the voltage is above the first predetermined limit and below the second predetermined limit.

Abstract: An adaptable electrical braking system for an electrical propulsion system of a traction vehicle is provided. The electrical braking system is configured to dissipate electrical energy in a plurality of resistor grids. The braking system includes a braking system assembly including a baseline chopper circuit topology. The baseline chopper circuit topology includes a first semiconductor-based circuitry in an enclosure for accommodating the first semiconductor-based circuitry. The braking system further includes a second semiconductor-based circuitry electrically coupled to the first semiconductor-based circuitry to produce a chopper including a chopper circuit topology fully contained in the enclosure. The second semiconductor-based circuitry includes a circuit topology selectable to adapt the baseline chopper circuit topology to meet distinct operational requirements to be fulfilled by the braking system.

Abstract: A fan system includes a stator magnetic pole, a driving unit and a real-time stopping unit. The driving unit is coupled with the stator magnetic pole and controls a polarity change of the stator magnetic pole in accordance with a driving signal. The real-time stopping unit is electrically connected with the driving unit. When the fan system is powered off, the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

Abstract: A storage drive implements a method for a BEMF voltage reduction during a deceleration period of an electric motor of the storage drive. In operation, the electric motor is disconnected from a power supply during an entirety of the deceleration period of the electric motor to prevent any flow of a BEMF current into the power supply, and the electric motor is connected to a power return during a segment or an entirety of the deceleration period of the electric motor to dissipate any BEMF voltage within the electric motor.

Abstract: To stop, in an emergency, a revolving superstructure quickly from rotating while preventing damage of a mechanical brake. A revolving superstructure is driven swiveling using a permanent magnetic-type swiveling electric motor; in an emergency, such as a malfunction in a drive or control system for the swiveling electric motor, allowing electric power generated in the electric motor due to inertial rotation to be consumed in an external braking resistor so as to make an electric braking action; and a mechanical brake is activated to stop the rotation and hold the stopped revolving superstructure when a rotation speed of the revolving superstructure becomes equal to or lower than a preset value.

Abstract: A parallel two-wheeled vehicle including a braking mechanism to directly brake two wheels that includes: a body; a pair of drive units coaxially mounted to the body; a T-shaped handle to be gripped by a passenger; a longitudinal inclination detecting device of the body; and a brake lever. A brake detecting device detects operational information of the brake lever. The body includes: a vehicle speed detecting device to determine a vehicle speed based on a relative angular velocity between the body and the wheels, which is detected by the drive units and based on an angular velocity detected by the longitudinal inclination detecting device; a target speed setting device to set a target vehicle speed based on an output of each of the brake detecting device and the vehicle speed detecting device; and a stabilization control device to control the vehicle to stably follow the target angle/target angular velocity/target vehicle speed. Further, powder brakes are incorporated in the drive units, respectively.

Abstract: A generator-brake integration type rotating machine comprises an inertia disk coupled to a shaft to rotate; a rotor ring rotating around the shaft inside the inertia disk and having magnets mounted to a circumferential outer surface thereof; and a laminated yoke positioned between the inertia disk and the rotor ring, and having brake coils located at regular angular intervals on a circumferential outer surface thereof and generator coils located at regular angular intervals on a circumferential inner surface thereof. The generator coils are wound on first bobbins which project inward from the circumferential inner surface of the laminated yoke, and the brake coils are wound on second bobbins which project outward from the circumferential outer surface of the laminated yoke. The laminated yoke is fixedly coupled to a stator holder, which in turn is coupled to the shaft by way of a bearing and is fixedly coupled to a housing.

Abstract: A kit and method for reconfiguring an electrical braking system for a traction vehicle are provided. The kit may include a braking system assembly including a chopper having a first chopper circuit topology. The first chopper circuit topology includes a first semiconductor-based circuitry having a footprint that defines at least one cavity in an enclosure for accommodating the first semiconductor-based circuitry. This enclosure constitutes the enclosure for accommodating the semiconductor-based circuitry in the chopper having electromechanical-based circuitry and semiconductor based circuitry. A second semiconductor-based circuitry is arranged in the at least one cavity in the enclosure for accommodating the first semiconductor-based circuitry. The second semiconductor-based circuitry when electrically coupled to the first semiconductor-based circuitry produces a chopper comprising a second chopper circuit topology fully contained in the enclosure.

Abstract: Certain exemplary embodiments comprise a system comprising a plurality of Active Front End units adapted to be electrically coupled to a direct current (DC) bus. Each of the plurality of Active Front End units can be adapted to be electrically coupled to a separate winding of a transformer of a plurality of transformers. Each of the plurality of Active Front End units can be adapted to convert alternating current (AC) voltage to a DC voltage. Each of the plurality of Active Front End units can be adapted to supply the DC voltage to the DC bus. The DC bus can be adapted to be electrically coupled to a plurality of inverters.

Abstract: A reverse current detection unit detects the direction of the motor current during the synchronous rectifier period based on the polarity of the on voltage of a switching device contained in the motor current path, and outputs a reverse current detection signal representing the result of this detection to the PWM control unit. Change in the output of the PWM control unit that generates the drive signal for a particular switching device in the drive unit is controlled based on the reverse current detection signal and the energizing pattern of the drive unit is changed when motor current is detected in the synchronous rectifier period to be flowing in the opposite direction as in the urging period. The flow of motor current to the power supply is thus reduced and a rise in the power supply voltage can be prevented.

Abstract: A stabilizer control device includes: an electric motor having a regenerative function; a stabilizer, connecting a left wheel and a right wheel, that is capable of altering a roll rigidity via the electric motor; vehicle behavior detection device that detects a vehicle behavior; regenerative current setting device that sets a regenerative current of the electric motor based on the vehicle behavior detected by the vehicle behavior detection device; and regenerative current adjusting device that adjusts the regenerative current of the electric motor so that the regenerative current set by the regenerative current setting device is reached. The spring reaction force against the twist of the stabilizer rotates the electric motor to thereby generate electricity. Vehicle behavior such as body roll is detected and the regenerative current of the electric motor is set based on the detected vehicle behavior to restrain or accelerate the twist or return of the stabilizer.

Abstract: A dynamic braking circuit for an electronic motor drive shunts the DC link of the drive with a resistor using two control strategies. The first control strategy used for lower levels of braking employs a pulse width modulated signal and the second control strategy used for higher levels of braking uses a hysteretic signal significantly reducing switching losses in the semiconductor devices controlling the dynamic braking resistor allowing higher braking capacity.

Abstract: A circuit for determining a direction of rotation of an electric motor, the motor having asymmetry and/or eccentricity in a profile of back electromotive force as a function of angular position of a rotor with respect to a stator, the circuit receiving a signal representing the BEMF, and use the corresponding asymmetry and/or eccentricity in the signal to derive the direction of rotation. The signal representing the back emf can be generated by a control circuit. The control circuit can have a feedback loop regulator to generate a control signal (TL or TR) to control a current drive circuit (11,12) to control an amplitude of current (iw) in the windings, the feedback loop regulator being arranged to compare the amplitude of the current (iw) in the windings with a reference value (iset), and use the control signal to provide the signal representing the back electromotive force.

Abstract: The servo motor is controlled by a control signal from a control circuit. A common branch line is separated from a positive common line in accordance with information that a safety door is opened. Thus, a first gate drive circuit group is made inoperative. Then, a second gate drive circuit group is operated to thereby short-circuit the U?, V? and W?phases of the motor to place in a regenerative braking state.

Abstract: A regenerative braking method for a vehicle having an electric motor. During an initial stage of a regenerative braking operation related to the vehicle having the electric motor, a flow rate of brake liquid as much as the amount of regenerative braking is delivered into a reservoir through opened exit valves of non-driving wheels, so as to generate a hydraulic braking force needed after subtracting the amount of regenerative braking from the amount of braking desired by a vehicle operator. When the amount of regenerative braking increases, exit valves of driving wheels are controlled to fulfill the total amount of braking desired by the vehicle operator. Also, when the amount of regenerative braking decreases, wheel pressures have to be increased to fulfill the vehicle operator's desire to brake.

Abstract: A braking device for an electrically driven rotor comprises a drive signal generating circuit for an electrically driven rotor, an output stage, a motor for the electrically driven rotor, driven by the output stage, and a monitor circuit for detecting interruption of an electric power supply for the motor. The output stage has a MOSFET of an upper stage side and a MOSFET of a lower side, and a diode inserted between a gate of the MOSFET of the lower stage side and the electric power supply. An electromagnetic brake is generated and applied on the electrically driven rotor when the MOSFET of the upper stage side is turned OFF and the MOSFET of the lower stage side is turned ON by a control signal from the monitor circuit, and an exciter coil of the motor is shorted when the electric power supply is interrupted.

Abstract: An electronic braking and energy recycling system associated with a direct current (DC) brushless motor, characterized in that when an electronic braking task is launched, a phase voltage occurred in an inverse mode is applied onto a motor coil corresponding thereto and a gate voltage signal with positive and negative cycles is used to control an upper-side and lower-side branches to switch as compared to each other in the system, so as to redirect a current flown through the motor back to a power source end. In this invention, a controllable inverse torsion is achieved, enabling an electrical machine to be braked smoothly and reliably when necessary. As such, a dynamic power of the motor can be recycled at a maximum rate and thus the purpose of energy recycling is achieved. In addition, no complex circuitry configuration owing to the multi-phase coils is required.

Abstract: A load-lifting apparatus has one or more prime power sources, one or more energy storage systems and regenerative braking. Regenerative energy is recovered when the load-lifting apparatus lowers its load. The elements of the prime power sources, energy storage devices and electrical components may be distributed to provide stability for the load-lifting apparatus. The general power architecture and energy recovery method can be applied to cranes, rubber-tired gantry cranes, overhead cranes, mobile cranes, ship-to-shore cranes, container cranes, rail-mounted gantry cranes, straddle carrier cranes and elevators. In such an architecture, the energy storage system helps alleviate the power rating requirement of the prime power source with respect to the peak power requirement for lifting a load.

Abstract: The invention relates to a diesel-electric drive system comprising a permanently excited synchronous generator (4), which is mechanically coupled to a diesel motor (2) on the rotor side and has an electrical connection to a voltage link converter (6) on the stator side, said converter having a respective self-commutated pulse-controlled converter (12, 14) on the generator and load sides. The converters are interconnected on the d.c. voltage side by means of a d.c. link (18). The system also comprises a braking resistor (20), which can be electrically connected to said d.c. link (18). According to the invention, a multi-phase braking resistor assembly, which can be electrically connected in series to the multi-phase stator winding system (74) of the permanently excited synchronous generator (4) by means of a multi-phase actuator (32), is provided as the braking resistance.

Abstract: This electric safety braking device for an electric traction vehicle may allow the force/speed characteristic of the vehicle to be improved and includes a rotating electromechanical machine with permanent magnets which has at least one coil with electric terminals, a rheostatic electric braking torque production device, and a commutation device which are capable of connecting the electric terminals of the electromechanical machine to the braking torque production device. The electric safety braking device includes at least one inductor is connected in series between the braking torque production device and the electromechanical machine.

Abstract: A braking system for electric step motors that operate in conjunction with a light assembly, including a moving head for pan or tilt thereof or for moving internal optical components. The step motors are connected to driving means to reduce movement speed of the moving head during power down and are connected through switches with a first operating position to connect the driving means to the step motors, and with a second power down position to establish a current path through a motor winding. Movements after power down take place very slowly and without generating noise for use in a theatre where the lamp may be switched off because a fuse burn out, and so cease operation without making disturbing noise. In a controlled power down, noise is reduced when several lamp fixtures placed side by side at the same time move to a stop position.

Abstract: The invention relates to a diesel-electric drive system comprising a permanently excited synchronous generator (4), which is mechanically coupled to a diesel motor (2) on the rotor side and has an electrical connection to a voltage link converter (6) on the stator side, said converter having a respective self-commutated pulse-controlled converter (12, 14) on the generator and load sides. The converters are interconnected on the d.c. voltage side by means of a d.c. link (18). The system also comprises a braking resistor (20), which can be electrically connected to said d.c. link (18). According to the invention, each connection (R, S, T) of the pulse-controlled converter (12) in the voltage link converter (6) on the generator side can be electrically connected to a respective braking resistor (34, 36, 38) by means of an actuator (32), said connections being electrically interlinked. This permits the provision of a diesel-electric drive system that no longer requires an additional brake attenuator.

Abstract: When surplus power not charged to an electric storage is generated at the time of regenerative braking of a vehicle, a voltage is generated across first and second neutral points using a zero-voltage vector each of first and second inverters and the generated surplus power is consumed by a resistance connected across the first and second neutral points. The voltage generated across the first and second neutral points is calculated in accordance with the surplus voltage, using a resistance value of the resistance.

Abstract: A kit and method for reconfiguring an electrical braking system for a traction vehicle are provided. The kit may include a braking system assembly including a chopper having a first chopper circuit topology. The first chopper circuit topology includes a first semiconductor-based circuitry having a footprint that defines at least one cavity in an enclosure for accommodating the first semiconductor-based circuitry. This enclosure constitutes the enclosure for accommodating the semiconductor-based circuitry in the chopper having electromechanical-based circuitry and semiconductor based circuitry. A second semiconductor-based circuitry is arranged in the at least one cavity in the enclosure for accommodating the first semiconductor-based circuitry. The second semiconductor-based circuitry when electrically coupled to the first semiconductor-based circuitry produces a chopper comprising a second chopper circuit topology fully contained in the enclosure.

Abstract: The invention relates to a vehicle electric drive system. There is a need for a brake responsive vehicle electric drive system. A vehicle electric drive system includes an internal combustion engine, an electric motor/generator driven by the engine, and drive wheels driven by a traction motor/generator. The motor/generators are controlled by a control system which receives signals from an operator speed control member, wheel speed sensors, and a pair of brake pedal position sensors, each connected to a corresponding left or right brake pedal. In response to operation of the brake pedals, the controller coordinates operation of the electric drive system with operation of the brake pedals.

Abstract: A method for controlling an electromagnetic retarder. More specifically, the method relates to determining, in a control unit, a maximum allowable intensity (Im) of an excitation current to be injected into an electromagnetic retarder (1). The retarder includes a shaft bearing secondary windings (5) and field coils (13) which are supplied by the secondary windings (5), the primary coils (8) and secondary windings (5) forming a generator. The retarder also includes a jacket (9) inside which the field coils (13) generate Foucault currents and a circuit for the liquid cooling of said jacket. The method consists in determining the maximum intensity in real time from data and values that are representative of the speed of rotation of the rotary shaft, the heat load that the cooling circuit can dissipate and the flow rate (D) of the coolant. The method is suitable for electromagnetic retarders which are intended for vehicles such as heavy vehicles.

Abstract: A disk drive system is set forth that comprises a rotatable storage medium adapted to store data, a spindle motor disposed to rotate the rotatable storage medium, and a spindle motor control system. The spindle motor control system brakes rotation of the spindle motor in response to inductive sensing of the rotation of the spindle motor.

Abstract: A drive, including at least a brake and an electromotor, is connected to an output stage with the aid of supply lines, the brake being supplied from a brake control, the brake control being connected to the supply lines for its supply, via capacitors.

Abstract: An electric powertrain for use with an engine and a traction device is disclosed. The electric powertrain has a DC motor/generator operable to receive at least a portion of a first mechanical output from the engine and produce a DC power output. The DC motor/generator is also operable to receive DC power and produce a second mechanical output. The electric powertrain further has a drivetrain operable to receive the DC power output and use the DC power output to drive the traction device. The drivetrain is also operable to generate DC power when the traction device is operated in a dynamic braking mode.

Abstract: A car control apparatus including a wheel sensor, wheel torque calculating means for calculating wheel torque from the wheel speed, drive force detecting means for detecting drive force generated by an electric motor, car body drive force calculating means for calculating car body drive force from the above drive force and wheel torque, car body drive force fluctuating component extracting means for extracting multiple frequency band fluctuating components of the car body drive force, and drive or braking force control unit for controlling the running state of a car.

Abstract: In such a product that torque of a motor is continuously generated when a rotation number of the motor is nearly equal to zero, since an output voltage is kept at a constant value in accordance with a rotation position of the motor, such a condition that currents are concentrated in a specific element are maintained. As a result, a temperature of the specific element is increased, so that there are problems that a temperature fail of an inverter apparatus may readily occur, and thus, lifetimes of elements are lowered. In a power converter of a motor drive apparatus, windings are energizing-controlled in such a manner that only 1 phase of a switching circuit is pulse-width-controlled when the motor is under motor locking condition.

Abstract: The invention relates to a vehicle electric drive system. There is a need for a brake responsive vehicle electric drive system. A vehicle electric drive system includes an internal combustion engine, an electric motor/generator driven by the engine, and drive wheels driven by a traction motor/generator. The motor/generators are controlled by a control system which receives signals from an operator speed control member, wheel speed sensors, and a pair of brake pedal position sensors, each connected to a corresponding left or right brake pedal. In response to operation of the brake pedals, the controller coordinates operation of the electric drive system with operation of the brake pedals.

Abstract: A frequency converter assembly comprising a direct-voltage circuit and brake chopper means, the direct-voltage circuit including a first branch (DC+) and a second branch (DC?), and the brake chopper means including a first terminal (BRK+), a second terminal (BRK?), a brake chopper switch (S1) and control means (2). The brake chopper switch (S1) is arranged in its closed position to provide a braking connection, in which the first branch (DC+) is electrically connected to the first terminal (BRK+) and the second branch (DC?) is electrically connected to the second terminal (BRK?). The assembly is provided with a first operating state where the control means (2) are arranged to control the brake chopper switch (S1) selectively to the closed position and the open position in response to the desired power supply direction of the direct-voltage circuit.

Abstract: A turbogenerator/motor controller with a microprocessor based inverter having multiple modes of operation. To start the turbine, the inverter connects to and supplies fixed current, variable voltage, variable frequency, AC power to the permanent magnet turbogenerator/motor, driving the permanent magnet turbogenerator/motor as a motor to accelerate the gas turbine. During this acceleration, spark and fuel are introduced in the correct sequence, and self-sustaining gas turbine operating conditions are reached. The inverter is then disconnected from the permanent magnet generator/motor, reconfigured to a controlled 60 hertz mode, and then either supplies regulated 60 hertz three phase voltage to a stand alone load or phase locks to the utility, or to other like controllers, to operate as a supplement to the utility. In this mode of operation, the power for the inverter is derived from the permanent magnet generator/motor via high frequency rectifier bridges.