Abstract: The invention relates to a method for deterring theft of a vehicle having a three-phase electric motor without a freewheel (10), comprising the steps of using the motor in a generator mode to power a motor control circuit (14) in an initial phase of rotating the motor through motion of the vehicle; and, when the power supply level of the control circuit reaches a first threshold (Vmin), connecting by the control circuit first and second phases (b, c) of the three-phase motor continuously to a first power supply line (Vss), whereby the first and second phases are short-circuited and cause an increased braking force of the motor. During this time, the third phase of the motor may be connected to continue to supply energy to the control circuit.

Abstract: A motor control system shorts motor windings of a motor by using junction gate field-effect transistors (JFETs) controlled bipolar junction transistors (BJTs), solid state relays (SSRs) controlled BJTs, and depletion mode metal-oxide-semiconductor field-effect transistors (MOSFETs) so that the motor generates braking torque when all or some electric control units of the motor are disabled or failed. The motor control system comprises: a motor comprising a plurality of motor phase terminals; a plurality of electric control units electrically connected with the motor and configured to control the motor, wherein the electric control units are configured to output control signals, respectively; and a shorting circuit connected to between the motor and the electric control units, the shorting circuit configured to short the motor phase terminals in response to receiving none of the control signals from the electric control units.

Abstract: A fan brake circuit includes a semiconductor switch unit, a motor, a motor drive circuit, an isolation unit, a charging/discharging unit and a control unit. One end of the motor, the semiconductor switch unit and the control unit serves to receive an input power. When the fan is powered off, the semiconductor switch unit disconnects from the motor and the motor drive circuit receives the operation voltage provided by the charging/discharging unit and transmits the drive signal to the motor, whereby the motor forms a short-circuit to brake. By means of the design of the fan brake circuit, when the fan is powered off, the fan can quickly brake and stop and the cost is lowered.

Abstract: There is provided an electric motor comprising a rotor, a stator and a motor controller. The stator comprises a substantially cylindrical body, a plurality of teeth extending from the substantially cylindrical body in a radial direction, one or more first sets of electrical windings that are wound around said teeth and configured to drive the rotor, and one or more second sets of electrical windings electrically separate from the first set of electrical windings. The second set of electrical windings on the stator are electrically connected to the motor controller such that energy produced by the electric motor during a regenerative mode of operation in use is diverted to the second set of electrical windings on the stator for dissipating the energy produced in the regenerative mode.

Abstract: A control circuit, a system and a method 200 of determining a position of a rotor in a permanent magnet motor PM1 in a state when the rotor is freely rotating, the motor being connected to a direct voltage link 101 via an inverter circuit 102, wherein the inverter circuit is operable for connecting windings of a stator of said motor to the direct voltage link, the method comprising the following a step a) short circuiting 201 the windings of the stator of said permanent magnet motor, a step b) measuring 202 a back electromotive force EMF of the short-circuited windings of the stator; and a step c) determining 203 the position of the rotor by means of the measured back EMF.

Abstract: Embodiments of the present invention provide a method for controlling compressor braking, a frequency converter and a variable speed compressor. The method includes steps of: determining to brake a compressor, wherein a brake circuit includes three switching units and the three switching units are respectively electrically connected to three phases of windings of a motor of the compressor; actuating two of the three switching units to short-circuit two phases of windings of the motor. The two phases of windings of the motor are short-circuited by controlling the three switching units to generate braking torque, such that the compressor is braked without introducing a DC voltage, and thus the braking energy consumption is reduced. Besides, by turning on only two switches at a time, the switching abrasion is reduced, and the overall service life of the three switching units is effectively improved.

Abstract: A control device for an electrical device such as an electric motor is provided. The control device is designed to, when necessary, bring about a safe, torque-free state of an electric motor, in particular a field-weakened electric motor. The control device includes a safety unit which is designed to generate safety control signals.

Abstract: A method and apparatus for catching a rotating motor is described. Switches (typically the lower switches) of an inverter of a motor drive circuit are short-circuited for a brief period of time. The pulses generated by this process are analyzed to determine the speed and direction of rotation of the motor. The pulses are checked to determine whether they are orthogonal. If they are, the motor velocity determination is deemed to be reliable and then motor is magnetized and normal motor control can be resumed. If not, the motor velocity determination is deemed to be unreliable and a magnetization pulse before the velocity determination step is repeated.

Abstract: A motor-driven compressor includes a compression unit that includes movable and fixed scrolls and a compression chamber, an electric motor that includes a rotor and drives the compression unit, a motor drive circuit that drives the electric motor, an injection port that draws intermediate pressure refrigerant into the compression chamber, a controller that performs rotation control on the rotor, and a voltage detector that detects a terminal voltage of the electric motor. The compression unit compresses low pressure refrigerant drawn into the compression chamber to discharge high pressure refrigerant. The controller is configured to output a stop instruction to deactivate the rotation control of the rotor, determine a rotation condition of the rotor based on the voltage detected by the voltage detector after outputting the stop instruction, and perform, based on the determination, restart preparation control that includes outputting a lock instruction to electrically stop rotation of the rotor.

Abstract: An air conditioner, a method and a device for controlling a compressor in the same are disclosed in the present disclosure. The method includes: during a shutdown process of the air conditioner, controlling a drive circuit of the compressor to short three phase windings of the compressor if receiving a stop signal for stopping the compressor; and controlling a rotor of the compressor to stop according to a brake torque generated by shorting the three phase windings, to stop the compressor. The method shorts the three phase windings by controlling the drive circuit, thus to generate the brake torque to control the rotor to stop faster. As a result, the method enables the compressor to stop and to stay still rapidly, thereby facilitating to reduce a piping stress in the air conditioner and to prolong a working life of a pipe in the air conditioner.

Abstract: In one aspect of the present disclosure, an electric working machine includes a three-phase brushless motor, a first switching element, a second switching element, a third switching element, a fourth switching element, a fifth switching element, a sixth switching element, a rotation detector, a brake controller. The brake controller executes a two-phase short-circuit brake. The two-phase short-circuit brake is executed so as to switch any of the fourth switching element, the fifth switching element, and the sixth switching element to a corresponding ON-state or an OFF-state in response a detection signal from the rotation detector that occurs prior to a switching time.

Abstract: A brushless motor device configured to: determine a first upper limit of a current value which flows through a coil when a rotation speed of a rotor is accelerated from a first speed to a second speed, wherein, in a case where the current value of the first upper limit flows through the coil when the rotor is rotated at the second speed, a first time period, which is from a start of a non-energization time period of the coil until an induced voltage reaches a threshold value, is longer than a second time period, which is from the start of the non-energization time period until a counter-electromotive voltage becomes zero; and change switching of each switching element of an inverter circuit by using a second upper limit greater than the first upper limit and the first upper limit.

Abstract: An electric working machine in one aspect of the present disclosure includes a motor, a first switching element, a second switching element, a rectifier element, and a controller. The controller is configured to perform a stop control, in which completion of a first current path is maintained via the first switching element for a specified period and a second current path is interrupted via the second switching element, in response to satisfaction of a stop condition for stopping power supply from a power source to the motor during rotation of the motor.

Abstract: The invention relates to an operating state circuit for actuating an inverter (3), which supplies an n-phase electrical machine (5) with an n-phase supply voltage via phase connections (4a, 4b, 4c), wherein n?1, comprising an evaluation device (6) which is connected to the phase connections (4a, 4b, 4c) of the inverter (3) and which is configured to detect output voltages of the inverter (3) to the phase connections (4a, 4b, 4c) and to determine a speed of the electrical machine (5) on the basis of the detected output voltages, and an actuating device (7) which is coupled to the evaluation device (6) and which is configured to switch to an idle state or an active short-circuit in dependence on the determined speed of the inverter (3).

Abstract: A fan motor braking apparatus and a method of controlling the same provide a braking protection before the fan motor revolves. The fan motor braking apparatus includes a conversion circuit, a braking enable circuit, a braking release circuit, and a fan motor startup circuit. The conversion circuit has a plurality of power switch elements electrically connected to the fan motor. The braking enable circuit is connected to the conversion circuit and the braking release circuit is connected to the braking enable circuit. The fan motor startup circuit receives an external DC voltage. The braking enable circuit generates a braking control signal to turn on the power switch elements when the braking enable circuit receives the external DC voltage, thus braking the fan motor.

Abstract: The present disclosure relates to a multi-tiered lighting system that has a pole and at least two light sources. A first light source is mounted to the pole at a first height, and a second light source is mounted to the pole at a second height that is substantially different than the first height. The first light source is configured to project a first beam of light that primarily lights up a first portion of a target coverage area, and the second light source is configured to project a beam of light that primarily lights up a second portion of the target coverage area, which is different from the first target coverage area. The first beam of light may spill onto the second target area, and the second beam of light may spill onto the first target area.

Abstract: One aspect of an embodiment of the present disclosure is a braking apparatus for an electric power tool that includes a switching circuit with six switching elements and a brake control unit. The brake control unit switches any one selected switching element of three switching elements forming one selected switch group of a high-side switch group and a low-side switch group to an off state from an on state at a timing at which braking current flows through a diode connected in parallel to the selected switching element upon turn-off of the selected switching element.

Abstract: A motor controller for an electric motor having a stator and a rotor. The motor controller includes a power input for receiving AC power from a power source; a control input for receiving a control signal from a control; and circuitry for switching power from the power source to the electric motor in response to the control signal. The circuitry is operable to: apply a braking waveform to the stator while the rotor is rotating; monitor a reactive power of the stator; detect an increase in the reactive power of the stator to determine the rotor has substantially stopped rotating; and remove the braking waveform from the stator in response to detecting the increase in the reactive power.

Abstract: One embodiment of a drive system may include a motor shaft coupled to a gear set in connection between an input shaft and an output shaft. The system may also have a direct current motor selectively holding the motor shaft in a fixed position for engaging the input and output shafts to one another in response to a sudden power loss from a main power supply. The system may further include an auxiliary power supply enabling the direct current motor to provide a resistive torque.

Abstract: The present disclosure relates to a method of controlling an inverter for driving a swing motor, and particularly, maximally generates braking torque of the swing motor upon generation of failure of the inverter by switching on/off a lower-phase switch or an upper-phase switch of the inverter in order to prevent an upper swing body from freely rotating which is generated when a semiconductor switch of the inverter is switched off upon the generation of over-current and over-voltage of the inverter that drives the swing motor, thereby being capable of protecting the inverter, rapidly stopping the upper swing body, and preventing the risk of accidents.

Abstract: Disclosed are a method and system for detecting a fault of a parallel coil type permanent magnet motor. This method includes driving a parallel coil type motor on the basis of a pre-defined current reference value, detecting a phase current vector of the motor, and calculating a current compensation value for removing a negative sequence component of the motor on the basis of the phase current vector.

Abstract: A motor controller for an electric motor having a stator and a rotor. The motor controller includes a power input for receiving AC power from a power source; a control input for receiving a control signal from a control; and circuitry for switching power from the power source to the electric motor in response to the control signal. The circuitry is operable to: apply a braking waveform to the stator while the rotor is rotating; monitor a reactive power of the stator; detect an increase in the reactive power of the stator to determine the rotor has substantially stopped rotating; and remove the braking waveform from the stator in response to detecting the increase in the reactive power.

Abstract: A motor control device has a drive circuit that drives an electric motor with a battery as a power supply, a switch element that is provided between the battery and the drive circuit, the switch element supplying a current from the battery to the drive circuit when being turned on, the switch element cutting off the current from the battery to the drive circuit when being turned off, a rotation speed detector that detects a rotation speed of the electric motor, and a controller that operates the drive circuit to control the electric motor. The controller turns on the switch element when the rotation speed of the electric motor, which is detected by the rotation speed detector, is greater than or equal to a first predetermined value during stopping of the control of the electric motor.

Abstract: An electric working machine including: a motor; a driving unit configured to be driven by the motor; a trigger switch configured to allow rotation of the motor; a power supply unit configured to supply electric power to the motor; and a control unit configured to control rotation of the motor, characterized in that: the electric working machine further comprises a switching element configured to perform short-circuiting between terminals of the motor to apply electronic braking, wherein the control unit is configured to perform adjustment of the braking by controlling the switching element when stopping the motor.

Abstract: A motor control device has a drive circuit that drives an electric motor with a battery as a power supply, a switch element that is provided between the battery and the drive circuit, the switch element supplying a current from the battery to the drive circuit when being put into an on state, the switch element cutting off the current from the battery to the drive circuit when being put into an off state, a voltage detector that detects a voltage at the drive circuit, and a controller that operates the drive circuit to control the electric motor. The controller turns on the switch element when the voltage at the drive circuit, which is detected by the voltage detector, is greater than or equal to a first predetermined value during stopping of the control of the electric motor.

Abstract: To provide a motor control device which can apply an electric brake to a motor when power supply is stopped, and achieve a miniaturization and a cost reduction. A first switch 11 through a sixth switch 16 connects respective coils L1, L2 and L3 included in a motor to an electric power source 20. The capacitor C accumulates the power supplied from the electric power source 20. A seventh switch 17 connects the capacitor C to a fourth switch 14 through the sixth switch 16, when the power supply from the electric power source 20 is stopped. The operation of the seventh switch 17 causes the fourth switch 14 through the sixth switch 16 to operate by the power accumulated in the capacitor C, and respective coils L1 to L3 are short-circuited to apply the brake to the motor.

Abstract: The invention relates to a motor drive for an on-load tap changer with an electrical DC motor and a braking device for denned braking of this motor. According to the invention, the braking device has a first diode (D1), which, depending on the direction of rotation, is connected in series with or in opposition to the armature winding (AW) of the DC motor. In accordance with a further feature of the invention, the braking device has a second diode (D2), which is connected permanently in parallel with the shunt winding (NW) of the DC motor.

Abstract: Certain embodiments are directed to devices, methods, and/or systems that use electrical machines.

Abstract: The invention relates to an industrial robot having a robotic arm. The robotic arm has several axes (A1-A6) and at least one electric drive, which comprises an electric motor (7-12) and power electronics (16) actuating the electric motor (7-12) and is equipped to move the relevant axis (A1-A6). The industrial robot (1) is equipped to short-circuit the electric motor (7-12) in the event of emergency braking simultaneously by means of two independent electric current paths.

Abstract: A switching device and method are disclosed for terminating a braking process of a three-phase AC motor. The braking process of the AC motor is performed by way of a first and second thyristor. During the braking process of the AC motor, in a first step the first thyristor is actuated in such a way that a braking current is fed to the AC motor, and therefore a torque which brakes the AC motor is produced. In a second step the second thyristor is actuated in such a way that, when the first thyristor is quenched, the braking current is taken on by the second thyristor and the braking torque is maintained. The two steps are repeated during the braking process; wherein the second step is suppressed during the braking process after a last actuation of the first thyristor.

Abstract: A motor controller for an electric motor having a stator and a rotor. The motor controller includes a power input for receiving AC power from a power source; a control input for receiving a control signal from a control; and circuitry for switching power from the power source to the electric motor in response to the control signal. The circuitry is operable to: apply a braking waveform to the stator while the rotor is rotating; monitor a reactive power of the stator; detect an increase in the reactive power of the stator to determine the rotor has substantially stopped rotating; and remove the braking waveform from the stator in response to detecting the increase in the reactive power.

Abstract: A variable speed switch includes a switch main body portion which is accommodated in a housing of an electric power tool and mounted to the housing so as to be capable of relative movement, and a load sensor which is provided in the switch main body portion and capable of outputting an electric signal in proportion to the amount of distortion caused by a pressing force. The switch operating portion is mounted on the surface of the housing so as to be capable of relative displacement with respect to the housing and transmits a pressing force applied to the switch operating portion to the load sensor, with the maximum displacement amount of the switch operating portion being set to equal to or less than 5 mm.

Abstract: A variable speed switch includes a switch main body portion which is accommodated in a housing of an electric power tool and mounted to the housing so as to be capable of relative movement, and a load sensor which is provided in the switch main body portion and capable of outputting an electric signal in proportion to the amount of distortion caused by a pressing force. The switch operating portion is mounted on the surface of the housing so as to be capable of relative displacement with respect to the housing and transmits a pressing force applied to the switch operating portion to the load sensor, with the maximum displacement amount of the switch operating portion being set to equal to or less than 5 mm.

Abstract: Representative embodiments of a system for braking a cyclically rotating motor upon a power failure include (i) charge-storage circuitry for storing charge and converting the stored charge to an output voltage upon power failure; (ii) one or more passive electrical elements for conducting current induced by motor rotations; and (iii) voltage-actuated circuitry connected to the passive electrical element and the charge-storage circuitry for braking the motor during each half-cycle of motor rotation. The circuitry is inactive until actuated by the charge-storage circuitry upon power failure.

Abstract: A switching device and method are disclosed for terminating a braking process of a three-phase AC motor. The braking process of the AC motor is performed by way of a first and second thyristor. During the braking process of the AC motor, in a first step the first thyristor is actuated in such a way that a braking current is fed to the AC motor, and therefore a torque which brakes the AC motor is produced. In a second step the second thyristor is actuated in such a way that, when the first thyristor is quenched, the braking current is taken on by the second thyristor and the braking torque is maintained. The two steps are repeated during the braking process; wherein the second step is suppressed during the braking process after a last actuation of the first thyristor.

Abstract: To provide a motor control device which can apply an electric brake to a motor when power supply is stopped, and achieve a miniaturization and a cost reduction. A first switch 11 through a sixth switch 16 connects respective coils L1, L2 and L3 included in a motor to an electric power source 20. The capacitor C accumulates the power supplied from the electric power source 20. A seventh switch 17 connects the capacitor C to a fourth switch 14 through the sixth switch 16, when the power supply from the electric power source 20 is stopped. The operation of the seventh switch 17 causes the fourth switch 14 through the sixth switch 16 to operate by the power accumulated in the capacitor C, and respective coils L1 to L3 are short-circuited to apply the brake to the motor.

Abstract: An electric brake system for an electromechanical machine connected to output terminals of an inverter, input terminals of which are supplied by a DC voltage source. The system includes an electrical circuit connected between the input terminals of the inverter and including, connected in series: a mechanism dissipating electrical energy returned by the electromechanical machine to the input terminals of the inverter during a braking phase of the electromechanical machine, including an inductor wound around a magnetic circuit; and a switching mechanism to close the electrical circuit during a braking phase of the electromechanical machine and to open the electrical circuit in absence of a braking phase of the electromechanical machine.

Abstract: The present invention relates to an electric device for driving mechanical equipment comprising an alternating current motor and an inverter, the said inverter comprising, for each phase of the said motor, an H bridge structure comprising four switching elements distributed over two branches connecting two terminals of the said H bridge structure and intended to supply the winding of the said at least one phase of the motor, the said winding being a winding with a mid point and the said electric device being characterized in that it also comprises, for each phase of the said motor, an energy storage unit, in particular a supercondenser, connected, on the one hand, to the mid point of the winding of the concerned phase of the motor and, on the other hand, to a terminal of the H bridge structure supplying the said winding.

Abstract: An assembly comprising a movable element being movable in relation to a base, a first electric motor for moving the element in relation to the base, the motor having one or more first windings each having at least two inputs, a first braking element being adapted to determine whether power and/or signals are provided to the first motor and being adapted to alter between at least two modes wherein, in a first of the modes, no power/signals is/are provided to the first motor and a first galvanic connection is provided between the inputs of at least one of the first windings and a first element having a predetermined resistance and wherein in a second of the modes, power/signals is/are provided to the first motor and the first galvanic connection is disconnected.

Abstract: The invention relates to a method for decelerating a drive movement of a power tool and to a power tool suitable for carrying out the method, having a drive driven by a motor, an energy supply device for the provision of electrical energy, a controller having a motor controller for activating the motor and an operating-state recognition module which is to detect at least one operating-state variable and, as a function of this, to output a brake signal, the controller being designed to initiate, as a function of the brake signal, a braking procedure in which brake cycles are provided which have a first time segment, in which the motor is short-circuited, and a second time segment in which current is fed to the motor opposite to its original direction of rotation.

Abstract: A drive system for an electric drive machine having an engine, a generator, a motor, final drive wheels and auxiliary devices is provided. The drive system may include an inverter circuit and an auxiliary driver. The inverter circuit may be coupled to each of the generator and the motor. The auxiliary driver may be coupled to each of the generator and the auxiliary devices. The inverter circuit and the auxiliary driver may be configured to automatically communicate power from the engine and any power from the auxiliary devices to the motor in a propel mode, and automatically communicate power from the motor to the engine, and optionally to a hybrid system if applicable, in a dynamic braking mode so as to minimize fuel consumption during the dynamic braking mode.

Abstract: The present disclosure relates to a method of controlling an inverter for driving a swing motor, and particularly, maximally generates braking torque of the swing motor upon generation of failure of the inverter by switching on/off a lower-phase switch or an upper-phase switch of the inverter in order to prevent an upper swing body from freely rotating which is generated when a semiconductor switch of the inverter is switched off upon the generation of over-current and over-voltage of the inverter that drives the swing motor, thereby being capable of protecting the inverter, rapidly stopping the upper swing body, and preventing the risk of accidents.

Abstract: An electrodynamic braking device for a universal motor includes a field winding configured to be fed from a grid during a braking operation, and an armature that is configured to be directly short-circuited. A braking process is performed by means of control electronics. Good braking is achieved with relatively low brush wear. Such an electrodynamic braking device can be used effectively for a power tool.

Abstract: A retarding system for an electric drive machine (100) includes a direct current (DC) link (312), at which a DC voltage is developed, disposed between a rectifier (206) and an inverter (208). A first contactor switch (216) electrically communicates with a first rail of the DC link (312), and a second contactor switch (216) electrically communicates with a second rail of the DC link (312). A first resistor grid (214) is connected in series between the first contactor switch (216) and the second contactor switch (216). The first resistor grid (214) dissipates electrical energy in the form of heat by conducting a current between the first rail and the second rail of the DC link (312) when the first contactor switch (216) and the second contactor switch (216) are closed.

Abstract: Methods and systems for operating an inverter coupled to an electric motor are provided. The inverter has a plurality of high switches and a plurality of low switches coupled to the electric motor. An event indicative of deceleration of the electric motor is detected. The inverter is alternated between a first mode of operation and a second mode of operation during the deceleration of the electric motor. In the first mode of operation, each of the plurality of high switches is activated and each of the plurality of low switches is deactivated. In the second mode of operation, each of the plurality of low switches is activated and each of the plurality of high switches is deactivated.

Abstract: A fan system including a motor with a coil, a storage unit, a driver, and a buffer circuit is provided. The coil module has a first connection terminal and a second connection terminal. The storage unit electrically couples with a voltage source, stores electrical energy when the voltage source is available, and releases the stored electrical energy to carry out a brake operation when the voltage source is unavailable. The driver electrically couples with the first and second connection terminals of the coil module to control a direction of an inductor current passing through the coil module. The buffer circuit electrically couples with the coil module. In the brake operation, the buffer circuit operates to form a transient potential between the first and second connection terminals of the coil module and to consume electrical energy of the inductor current, for gradually stopping the motor in a buffering time period.

Abstract: Methods of dynamic braking include two embodiments with braking circuits for vehicles such as, for example, locomotives which are operable down to very low speeds. These circuits can provide a braking force even at zero locomotive speed.

Abstract: A power transistor is arranged between an output terminal and a power supply terminal. A pre-driver includes a high-side transistor and a low-side transistor connected in series between the power supply terminal and a second terminal, and the ON/OFF operations of which are controlled in a complementary manner according to a control signal. The electric potential at a connection node between the two transistors is output to a control terminal of the power transistor. A constant voltage circuit stabilizes the second terminal to a predetermined voltage. An output transistor for the constant voltage circuit is provided between the second terminal and the ground terminal. A differential amplifier adjusts the voltage applied to the control terminal of the output transistor such that the electric potential at the second terminal approaches a predetermined target value. A feedback capacitor is provided between the second terminal and the control terminal of the output transistor.

Abstract: A control method of a current limit of a DC motor includes generating a reference voltage according to a preset current limit value of a DC motor; comparing the reference voltage with the voltage drop of a power control switch which drives the DC motor to generate a compare result; and controlling the power delivered to the DC motor according to the compare result in order to limit the current of the DC motor.

Abstract: A control apparatus is for use in a power conversion system including a DC/AC converter circuit connected to an electric rotating machine at output terminals thereof and to a DC power source at input terminals thereof through a switching means, a capacitor being connected across the input terminals of the DC/AC converter circuit. The control apparatus includes a current supply means configured to perform current supply control to supply a current to the electric rotating machine in order to discharge the capacitor by manipulating the DC/AC converter circuit in a state where the switching means is set open, and a speed lowering means configured to apply a brake force to a rotating shaft of the electric rotating machine to reduce a rotational speed of the electric rotating machine prior to the current supply control being performed by the current supply means if the rotational speed exceeds a specified speed.