Abstract: A method for controlling a performance of a dynamic braking system to maintain a dynamic braking tractive effort current plateau and/or improve the dynamic braking tractive effort current plateau, the method including sensing the traction motor field current and regulating the traction motor field current to maintain at least one of a constant armature current, a constant braking effort, and a constant field current based on the traction motor field current sensed. A system and a computer software code are also disclosed for controlling a performance of the dynamic braking system to maintain the dynamic braking tractive effort current plateau and/or improve the dynamic braking tractive effort current plateau.

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: In the present invention, several polyphase devices are connected together: an inverter, and electrical rotating machine, and a resistive load or braking resistor. The purpose of the resistive load is to dissipate excess electrical power which may be produced when the inverter acts to slow down the rotating machine, causing the rotating machine to act as a generator. In common art, this resistive load is a single DC resistor coupled to the DC link of the inverter via a separate resistor control transistor. In the present invention, the resistive load is a mesh connected array of resistors, and is electrically connected to the same inverter output terminals that the rotating machine is connected to. When it is desired that the resistors absorb energy, for example from a braking operation, then the harmonic content of the inverter output is adjusted, thus placing voltage differences across the resistor array and causing current to flow in the resistors.

Abstract: A method is proposed for braking a synchronous machine 1, with the armature windings (u, v, w) of the synchronous machine 1 being short-circuited, optionally by interposing at least one braking resistor. In order to keep the braking moment constant over virtually the entire speed range it is proposed that the short-circuit current is regulated by a pulse-width modulation depending on the difference between the setpoint value of the short-circuit current corresponding to the setpoint value of the braking moment and the actual value of the short-circuit current.

Abstract: A motor control apparatus supplying AC power to a motor having a plurality of motor windings having an inverting part including a bridge circuit having a plurality of switching units, and supplying the AC power to the motor; brake relays short circuiting the motor windings by turning on when the motor brakes; brake resistors, respectively, connected to the motor windings and consuming an overcurrent generated from the motor when the brake relays short circuit the motor windings; and a switching controller turning on and turning off the switching units provided in one of opposite ends of the inverting part so that the overcurrent consumed by the brake resistors is changeable in proportion to a rotation speed of the motor, when the brake relays short circuit the motor windings to improve an effect of a dynamic braking operation and to prevent breakdown thereof.

Abstract: An apparatus for controlling a rotational motion of a motor is disclosed which includes: a signal generator generating a rotational state signal indicative of a rotational state of the motor; and a controller producing a control signal for controlling the rotational motion of the motor, based on the rotational state signal generated by the signal generator, to thereby control the motor based on the produced control signal. The controller produces the control signal during a start up of the motor, such that the produced control signal is not affected by a noise component which is incorporated into the rotational state signal during the start up of the motor.

Abstract: Certain exemplary embodiments can provide for automatic power control and/or torque boost for retarding a machine that considers a machine weight and/or a machine slope. The automatic power control and/or torque boost can provide a control margin under retard. Certain exemplary embodiments can control, or attempt to control, a speed of the machine at less than a maximum safe speed.

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 motor has built therein a brake for stopping the rotation of the motor and a brake controlling circuit for controlling the brake. The motor is further provided with a bypass circuit for supplying an electric power directly to the brake and a terminal for connecting a power source to the bypass circuit. When the brake controlling circuit develops a fault, the brake is directly released by an external power source.

Abstract: An electric traction vehicle is described herein which may be used to provide power to off-board electric power-consuming systems or devices. The electric traction vehicle may provide 250 kilowatts or more of three phase AC power to an off-board electric power consuming system. The electric traction vehicle may also include an electrical power storage device which can be selectively discharged to allow the vehicle to be serviced.

Abstract: Am improved shaded pole A.C. motor with dynamic brake that includes a secondary high resistance winding that is selectively connected to a D.C. source when the A.C. voltage is removed. To stop a motor the A.C. voltage applied to the motor is removed with tandem switches that apply the D.C. voltage immediately upon removal of the A.C. voltage or the D.C. voltage can be selectively applied subsequently. The brake winding produces a magnetic flux in the same core where the main stator winding produces the magnetic flux responsible for causing the rotor to move. The brake winding can be connected in parallel during the time the A.C. voltage is applied to increase of the combined windings' inductance (resulting in an overall higher torque) and/or in series when during the braking operation when the D.C. voltage is applied to increase the combined winding's resistance (limiting further the peak D.C. current or reducing the secondary winding size).

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: The present invention relates to an actuator current control method. The method of the present invention comprising the steps of measuring a feedback current passing through an actuator, determining PWM duty according to an error component between a target current produced based on an input signal and the feedback current to generate a PWM signal, controlling a current supplied to the actuator based on the PWM signal, and monitoring the feedback current at a time difference of a half period in every period of the PWM signal to estimate an average current and then determining based on the estimated average current whether or not the control of the supplied current has failed. According to the present invention, an algorithm for monitoring a feedback current at a time difference of a half period in every period of the PWM signal to estimate an average current when measuring the average current of the actuator feedback current can be employed.

Abstract: The present invention provides an instantaneous fan stopping method and structure thereof. The method and structure can eliminate the inertial rotating state of the fan when the power supplied to the fan is cut off. In accordance with the present invention, a closed circuit is formed between the two terminals of the coil used to drive the fan. When the closed circuit is formed, the inertial rotation of the fan can generate an induced current in this coil, which, in turn, generates a magnetic force to stop the fan.

Abstract: A hybrid propulsion system. The system comprises one or more hybrid propulsion traction drives having an electric motor operable to produce mechanical power for propulsion. A hybrid propulsion traction drive is operable to receive power from an on-board power generation system. The electric motor is operable to receive power from an energy storage unit and operable to supply power to the energy storage unit. The energy storage unit may be coupled to the electric motor via a switch.

Abstract: An energy management control apparatus for a molding machine that includes a first electrically-driven prime mover configured to drive at least a first molding machine device, and a second electrically-driven prime mover configured to drive at least a second molding machine device, includes a common DC link configured to provide DC energy to the first electrically-driven prime mover and to the second electrically-driven prime mover. A slave axis is configured to supply and absorb energy from to/from the common DC link.

Abstract: A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking resistor and a control switching element disposed in parallel in an additional line connecting the pair of connection terminals to each other, a control switching element disposed with the breaking resistor in the additional line, a breaking switch disposed to one of the connection terminals and switched to either a normal position or a breaking position connecting the one connection terminal to a corresponding supply part or to the additional line, a speed detector detecting a motor speed and a control part controlling the breaking switch to switch to the breaking position and controlling the control switching element so that an on-off interval of the control switching element is controllable depending on the detected speed.

Abstract: The invention provides techniques for reducing or altering the magnetic noise of an AC rotary electric machine. A magnetic noise reducing harmonic current of order n, whose frequency is n times the frequency of the fundamental frequency component of a polyphase AC current fed to an armature of a polyphase AC rotary electric machine, is superimposed on the polyphase AC current, thereby reducing or altering a harmonic component having a frequency (n?1) times the frequency of the fundamental frequency component and occurring due to a radial magnetic excitation force acting radially on an iron core of the AC rotary electric machine.

Abstract: A braking chopper for dissipating braking power away from the direct-current rails of an AC drive system, said braking chopper being an inverter unit (INU) physically similar to those also used as motor supply devices, consisting of upper- and lower-branch controllable semiconductor switches (V1–V6), wherein the inverter is connected by its output connectors to the direct-current rails (DC) via a resistor unit, which resistor unit contains two resistors (R1, R2), of which the first is connected to the positive direct-current rail (DC+) and the second to the negative direct-current rail (DC?), wherein both lower-branch and upper-branch semiconductor switches are turned on during braking, and wherein one brake resistor is controlled by the lower-branch switch of only one phase and the second brake resistor by the upper-branch switch of another phase.

Abstract: A power supply apparatus driving and controlling motor generators (MG1, MG2) includes a battery (10) generating an input voltage (Vb), a converter (110) converting the input voltage into a motor operating voltage (Vm) according to a voltage command value (Vmr), a smoothing capacitor (120) holding the motor operating voltage, inverters (131, 132) receiving the motor operating voltage and driving and controlling the motor generators (MG1, MG2) according to a torque command value (Tref), and a control unit (15) generating the voltage command value and the torque command value.

Abstract: Certain exemplary embodiments can comprise a method comprising: receiving electrical energy from a braking system of a vehicle at a working coil, the vehicle comprising a first wheel drive comprising a first electric motor; and via the working coil, transferring the electrical energy to a mass related to the vehicle via Hall Effect, the transferred electrical energy converted to heat energy in the mass.

Abstract: This invention is a system and a method that uses the braking resistor, commonly used and available in electrically or hybrid-electrically propelled vehicles, to limit the precharge current during the startup of a high power ultracapacitor pack energy storage device and/or safely and rapidly discharge an ultracapacitor pack for maintenance work or storage to lengthen the life of the individual ultracapacitor cells and, correspondingly, the whole pack. The use of the braking resistor for precharging an ultracapacitor energy storage pack is an effective and less expensive method compared to other methods such as a separate DC-to-DC converter. This method includes the control logic sequence to activate and deactivate switching devices that perform the connections for the charging and discharging current paths.

Abstract: Certain exemplary embodiments can comprise a method comprising: receiving electrical energy from a braking system of a vehicle at a working coil, the vehicle comprising a first wheel drive comprising a first electric motor; and via the working coil, transferring the electrical energy to a mass related to the vehicle via Hall Effect, the transferred electrical energy converted to heat energy in the mass.

Abstract: A system and a method for determining operational states of first and second electrical contacts in a motor are provided. The motor has first, second, and third phase windings. The first phase winding is electrically coupled between first and second nodes. The second phase winding is electrically coupled between a third node and the second node. The third phase winding is electrically coupled between a fourth node and the second node. The first electrical contact is electrically coupled between the first node and the third node. The second electrical contact is electrically coupled between the third node and the fourth node. The method includes applying a first voltage signal to the first phase winding at a first time and measuring voltage signals at the third and fourth nodes to determine first and second operational states of the first and second electrical contacts.

Abstract: A vehicle driving force control apparatus is configured to prevent co-rotation of the motor caused by rotation of a pair of wheels when a clutch connecting the wheels and the motor is released (disconnected). When the clutch is released, the motor is braked by short circuiting the armature. The motor is then braked again by setting the field current of the motor to 0 when the rotational speed of the motor reaches 0. After the clutch is released, a braking-direction field current is applied to the motor in accordance with the decreasing rotational speed of the motor such that the braking force is decreased as the rotational speed of the motor decreases.

Abstract: When an angular acceleration ? of a rotating shaft of a motor connected with a drive shaft exceeds a preset threshold value ?slip, which suggests the occurrence of a skid, the torque control procedure sets a maximum torque Tmax by referring to a map, which gives a smaller maximum torque Tmax with an increase in angular acceleration ?, and restricts the motor torque to the maximum torque Tmax. The maximum torque Tmax is fixed to a value corresponding to a peak value of the angular acceleration ? at the time of occurrence of a skid. The torque control procedure then integrates the angular acceleration ? to give a time integration thereof over an integration interval when the angular acceleration ? once exceeds the preset threshold value ?slip and decreases again below the preset threshold value ?slip by the motor torque restriction.

Abstract: A drive unit of the invention comprises a motor that can input/output motive power to/from a drive shaft, a drive circuit that performs drive control of the motor, a fuel cell that is connected to the drive circuit without the intervention of a voltage converter such that electric power can be output, a charge/discharge portion that is connected to the fuel cell in parallel and to the drive circuit such that electric power can be output and that has at least one capacitor whose voltage in a fully charged state is higher than an inter-open-terminal voltage of the fuel cell, a diode that is installed between the fuel cell and the charge/discharge portion such that electric power can be output only in a direction from the fuel cell to the charge/discharge portion, and a drive control portion that controls the drive circuit such that drive control of the motor is performed on the basis of required motive power to be transmitted to the drive shaft.

Abstract: A method and apparatus for braking a motor has a braking circuit that intermittently shorts the windings of the motor to brake the motor. The braking circuit is powered by back EMF generated by the motor when power is disconnected from the motor.

Abstract: The present invention is directed to the termination of the occurrence of wheel slip/skid and prediction and prevention of the onset of wheel slip/skid in a locomotive. In one configuration, a lookup table of adhesion factors is used to predict the occurrence of wheel slip/skid.

Abstract: Certain exemplary embodiments can provide for automatic power control and/or torque boost for retarding a machine. The automatic power control and/or torque boost can provide a control margin under retard. Certain exemplary embodiments comprise a method comprising: for a machine comprising a wheel drive system comprising a braking system, comparing an acceleration to a predetermined acceleration threshold; determining a dynamic maximum retard torque associated with the braking system based on said comparing activity; controlling a retard torque to no greater than the dynamic maximum retard torque; and affecting a retard power.

Abstract: A method for reducing engine fuel consumption of an electro-motive vehicle during braking, the method including steps for providing an engine for the vehicle, generating primary electric power at a primary electric power generator connected to the engine, generating primary electric power at a secondary electric power generator connected to the engine, operating a plurality of electric traction motors each coupled in driving relationship to a respective one of a plurality of driven wheels to propel the vehicle during motoring operations and to generate electricity upon braking operations of the vehicle, electrically connecting a braking switch between the traction motors and the primary electric power generator, applying braking, closing the braking switch, and transmitting power generated by the traction motors to the primary electric power generator to operate as a motor to rotate the engine and drive the secondary electric power generator to power the auxiliary equipment without fueling the engine.

Abstract: A multi-stage dynamic braking resistor network (23) is provided that includes a plurality of dynamic brake resistors (1a–d) for dissipating, as heat, regenerative energy inputted onto a system bus (17) by a motor or actuator (19), and a plurality of switches (31a–d) for connecting the dynamic brake resistors (1a–d) to and from the system bus (17), respectively. The multi-stage dynamic braking resistor network (23) further includes a control circuit (25) for controlling the switches (31a–d) such that the dynamic brake resistors (1a–d) are connected to and from the system bus (17) on the basis of a predetermined voltage threshold of the system bus and on the basis of a predetermined rotation pattern.

Abstract: An electromagnetic suspension system for a vehicle, comprises an electromagnetic actuator interposed between a sprung mass and an unsprung mass and disposed substantially in parallel with an spring element. An electric motor is provided for driving the electromagnetic actuator. A motor controller is configured to calculate a displacement input applied to the electromagnetic actuator and to control the electric motor in a manner that the electromagnetic actuator generates an optimum damping force corresponding to the displacement input. A motor control circuit is provided for the electric motor, through which the electric motor is connected to the motor controller. Additionally, an electrical damping element is electrically connected to the motor control circuit and in parallel with the electric motor to generate a damping force in a passive manner under a dynamic braking of the electric motor in response to the displacement input to the electromagnetic actuator from the unsprung mass.

Abstract: The position and speed and, in some embodiments, direction of rotation of a motor for turning the rod of an object such as a window covering is determined by placing a braking magnet next to the motor and a piezoelectric element between the braking magnet and motor. As the motor rotates, the piezoelectric element generates a signal that can be used to determine the speed of rotation and also the position of the motor (and, hence, the position of the object being moved). The magnet brakes the motor from turning under the weight of the object when the motor is deenergized.

Abstract: The regenerative braking method and system for an electric vehicle in which regeneration current is calculated and controlled using control of an air conditioning system to consume a portion or all of the surplus regeneration power, thereby enhancing braking performance and feel. Control includes calculation of a regeneration current and comparison of the regeneration current to battery current to calculate the surplus regeneration power.

Abstract: According to an aspect of the invention, an electronic motor brake is provided which includes a braking circuit including one or more discharge devices connectable to one or more of a plurality of power supply lines carrying respective phases of a power supply for driving a direct current (DC) motor. Such electronic motor brake further includes an activation circuit driven by current returning from the motor through one or more of the power supply lines. The activation circuit is operable upon disconnecting the braking circuit from the plurality of the power supply lines to activate the discharge devices of the braking circuit to brake the motor.

Abstract: A motor power supply having an inrush current protection mode, a motor drive mode, an overvoltage protection mode, and a dynamic braking mode. In the inrush protection mode, a first resistance limits an inrush current to a capacitor which smoothes a rectifier output to provide DC power to an inverter during the motor drive mode. In the overvoltage protection mode, the first resistance is used in conjunction with a switching element to controllably discharge an overvoltage which may occur across the capacitor due to regenerated energy from the motor passing back through the inverter. During the drive mode, the inverter input is connected with the DC power and during the dynamic braking mode, the inverter input is connected with a second resistance which dissipates the energy regenerated by the motor. A controller controls a multi-contact relay and the switching element to implement the various modes of operation.

Abstract: There are provided as drive sources an engine 2, a front motor 3 provided on a front wheels 8 side of the vehicle and a rear motor 4 provided on a rear wheels 9 side of the vehicle, and in executing a regeneration of deceleration energy when braking, a regeneration capacity of the front motor 3 and a regeneration capacity of the rear motor 4 are calculated, respectively, so that the regeneration is executed with either of these motors 3, 4 which can provide a larger regeneration capacity.

Abstract: An apparatus for controlling deceleration of a DC motor which is driven in a forward operating direction with a forward-drive electric current applied thereto by a forward driving device, wherein the forward motor driving device applies the forward-drive electric current in the form of pulses to the DC motor during its deceleration, and wherein a plugging-braking device operable while the motor is subjected to a regenerative brake or operated in a non-braked state is operated to apply a reverse-drive electric current in the form of pulses to the motor, to apply a plugging brake to the motor, such that at least one pulse of the reverse-drive electric current follows every predetermined number of pulses of the forward-drive electric current.

Abstract: In the driving operation of a sensorless three-phase motor to be used in a rotation at a comparatively low speed (approximately 2000 RPM or less) and to be bipolar driven, the number of rotations and a rotating position are accurately detected from an induced voltage and a reverse rotation brake is applied in an accurate phase, and furthermore, a short brake is applied at a set rotation number signal or less also in braking. Consequently, it is possible to prevent phase switching from being carried out in an erroneous timing and to prevent a rotation in a reverse direction by an inertia.

Abstract: In an electronic system, motor braking is accomplished by applying direct current (DC) voltage, developed across a capacitive element during a run mode operation, across terminals of an alternating current (AC) or an induction motor. While the motor is ON, i.e. during the run mode operation, a diode rectifies an AC input voltage applied across a capacitor for charging thereof. Resistive elements in series with the capacitor control a charging rate thereof. When a relay or switch flips over to a STOP or OFF mode, i.e. a braking mode operation, all of the stored DC voltage, which was charged across the capacitor during the run mode operation, is dropped across a coil of the motor. This DC voltage creates an electric force applied to stop quickly and efficiently the motor shaft rotation. In preferred embodiments of the invention, it was found that the higher the capacitance of the electrolytic capacitor, the faster and more efficient the stopping action will be for the motor.

Abstract: A device for inrush current prevention and dynamic braking in a motor having a plurality of power inputting terminals, comprises a diode rectifying unit rectifying power supplied from an AC power supplying unit; a capacitor smoothing the power rectified by the diode rectifying unit; a resistor disposed between the AC power supplying unit and the capacitor, being connected to the capacitor; an inverter connected to terminals of the capacitor and the power inputting terminals of the motor, inverting the power from the capacitor into an AC power having multiple phases and supplying the AC power having multiple phases to the motor; a dynamic braking circuit short-circuiting the power input terminals of the motor; and a relaying unit including a first node connecting the dynamic braking circuit to the resistor and a second node connecting the diode rectifying unit to the capacitor in parallel.

Abstract: A device to control a 3-phase motor having an inverter connected to each phase terminal and a brake to arrest the 3-phase motor, includes a power supply to supply power to the brake and the inverter at the same time based on a predetermined synchronization signal. The device also includes a control unit to output an inverter control signal to control the inverter and a power control signal to enable the power supply to supply the power to the brake and the inverter. Thus, the device to control a 3-phase motor has an immediate response to a control signal with a reduced production cost and a system size, by reducing circuit components such as a brake relay and a brake power supply.

Abstract: A motor control circuit includes a forward rotation control circuit, a reverse rotation control circuit, and a brake control circuit. The forward rotation control circuit allows a first current source to supply a first current signal to a motor drive circuit for operating a motor in a forward rotation mode. The reverse rotation control circuit allows a third current source to supply a third current signal to the motor drive circuit for operating the motor in a reverse rotation mode. The brake control circuit allows a second current source and a fourth current source to respectively supply a second current signal and a fourth current signal to the motor drive circuit for operating the motor in a brake mode. The motor control circuit reduces power dissipation in the brake mode since the second and fourth current signals may be smaller than the first and third current signals.

Abstract: A method and apparatus for controlling a barrier movement operator comprising a controller that dynamically controls barrier operator braking to electronically slow, stop or reverse the motor in the barrier operator controller. The apparatus includes a source of electrical power for providing the necessary power to operate the apparatus, a converter for supplying power to a DC motor, and a controller for enabling dynamic braking of the movable barrier operator using electronic braking of the electric motor. The dynamic braking of the motor gradually slows movement of the barrier operator, thereby reducing forces acting on the motor and on the barrier.

Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.

Abstract: A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking resistor and a control switching element disposed in parallel in an additional line connecting the pair of connection terminals to each other, a control switching element disposed with the breaking resistor in the additional line, a breaking switch disposed to one of the connection terminals and switched to either a normal position or a breaking position connecting the one connection terminal to a corresponding supply part or to the additional line, a speed detector detecting a motor speed and a control part controlling the breaking switch to switch to the breaking position and controlling the control switching element so that an on-off interval of the control switching element is controllable depending on the detected speed

Abstract: A dynamic braking system for a vehicle, the system comprising an engine, an alternator, a plurality of alternating current (AC) electric traction motors, each coupled in driving relationship to a respective one of a plurality of driven wheels, a plurality of power inverters where each of the traction motors has excitation windings coupled in circuit with a corresponding one of the plurality of power inverters, a fuel-free dynamic braking controller, a fuel-free dynamic braking transfer switch located between one of the plurality of traction motors and the one of the plurality of power inverters in circuit with the corresponding one of the plurality of power inverters, wherein the one of the plurality of traction motors in circuit with the corresponding one of the plurality of power inverters that is separated by the fuel-free dynamic braking transfer switch does not generate and does not consume power, and wherein the fuel-free dynamic braking controller commands one of the plurality of power inverters that i

Abstract: A power system for an electric motor drive such as may be used in an electrically propelled vehicle incorporates the combination of a high power density battery and a high energy density battery to provide an optimal combination of high energy and high power, i.e., a hybrid battery system. The hybrid battery system in one form includes components which prevent electrical recharge energy from being applied to the high energy density battery while capturing regenerative energy in the high power density battery so as to increase an electric vehicle's range for a given amount of stored energy. A dynamic retarding function for absorbing electrical regenerative energy is used during significant vehicle deceleration and while holding speed on down-hill grades, to minimize mechanical brake wear and limit excessive voltage on the battery and power electronic control devices.

Abstract: In the driving operation of a sensorless three-phase motor to be used in a rotation at a comparatively low speed (approximately 2000 RPM or less) and to be bipolar driven, the number of rotations and a rotating position are accurately detected from an induced voltage and a reverse rotation brake is applied in an accurate phase, and furthermore, a short brake is applied at a set rotation number signal or less also in braking. Consequently, it is possible to prevent phase switching from being carried out in an erroneous timing and to prevent a rotation in a reverse direction by an inertia.