Abstract: A Variable Speed Drive (1) for subsea installations (20), subsea vessels or subsea vehicles, as well as to a corresponding subsea installation (20), subsea vessel or subsea vehicle, has an alternating current/alternating current converter (2) having a current-controlled capacitor-less direct current link (7).

Abstract: Embodiments provide an electrical machine, comprising: first and second moveable elements arranged to interact in a magnetically geared manner via a magnetic field created, at least in part, by a first electrical winding arrangement associated with the first moveable element; and a second electrical winding arrangement which is arranged to interact magnetically with a fundamental harmonic of a magnetic field created by the first electric winding arrangement associated with the first moveable element.

Abstract: A method for controlling a motor propulsion unit including a motor including a permanent magnet rotor and a stator, the method including regulating currents of the stator so that they attain their setpoints by virtue of control signals, the currents to be regulated and the control signals being expressed in a rotating reference frame including a plurality of axes. The regulating includes for each of the axes of the plurality of axes applying, to the current to be regulated on the respective axis, a linear operator differing as a function of a value of the current to be regulated with respect to its setpoint, the result of the application of the linear operator being a control signal on the respective axis.

Abstract: An over temperature protection device for electric motors applicable to a railway vehicle driving system that operates a plurality of electric motors in parallel using one or a plurality of inverter devices includes a control device configured to control the operation of an inverter device and a protecting device configured to detect, on the basis of a frequency fs including frequency information at the time when the inverter device is applying control for fixing a ratio of a voltage and a frequency to electric motors and electric currents of at least one phase flowing to the electronic motors, an over temperature that could occur in the electric motors, to generate an over temperature protection signal Tf for protecting the electric motors from the over temperature, and to output the over temperature protection signal Tf to the control device.

Abstract: A control device of a three-phase AC motor includes: an inverter for driving the motor; a current sensor for sensing a sensor phase current of the motor; and a controller for controlling the motor. The controller includes: a current estimation device for estimating d-axis and q-axis current estimated values based on the sensor phase current and an electric angle of the motor; and a zero-crossing interpolation device for interpolating the d-axis and q-axis current estimated values by fixing the d-axis and q-axis current estimated values when the sensor phase current is in a zero cross range, which includes a zero point, so that the sensor phase current crosses the zero point, and for outputting interpolated d-axis and q-axis current estimated values as fixed d-axis and q-axis values, which are used for a feedback control relating to current flowing through the motor.

Abstract: A motor control system includes a plurality of motors, a plurality of inverters, and a controller. The plurality of inverters are configured to drive the plurality of respective motors and are coupled to a common bus line through which DC power is supplied. When power supply is interrupted, the controller is configured to calculate a frequency command value so as to maintain a bus line voltage across the common bus line and configured to supply the frequency command value to the plurality of inverters.

Abstract: A control device for a rotating electrical machine is provided that is capable of suppressing reduction in controllability of torque attributed to harmonic currents. According to the exemplary embodiment of the present invention, a designated torque value Trq* designated by a hybrid vehicle electronic control unit (HVECU) is corrected by a compensation amount ?Trq calculated using a harmonic voltage Vh, the designated torque value Trq*, and an electric angular velocity ? as inputs. An operating signal generating section generates an operating signal g¥# using a designated norm value Vn set based on the corrected torque designated value Trq* and a phase ? serving as a manipulated variable for performing feedback control of an estimated torque to the designated torque value Trq*, and outputs the generated operating signal g¥# to a power supply circuit of a motor generator.

Abstract: A controller for a brushless motor that is configured to operate in normal mode or under-voltage mode. When operating in normal mode, the controller generates control signals for exciting a winding of the motor, monitors the magnitude of an input voltage, and switches to under-voltage mode in the event that the input voltage drops below an under-voltage threshold. When operating in under-voltage mode, the controller suspends excitation of the winding, monitors the magnitude of the input voltage, monitors the magnitude of a supply voltage used to power the controller, switches to normal mode in the event that the input voltage exceeds a restart threshold, and resets itself in the event that the supply voltage drops below a brown-out threshold.

Abstract: An AC motor controller is provided that utilizes a direct torque controller and primary and secondary control loops. The primary control loop operates in a relatively conventional manner, determining a voltage vector that sets the inverter switching variables for the motor's power inverter, where the voltage vector is based on the motor's torque and flux as estimated from the measured voltage and current of the motor. The secondary loop, utilizing a faster sampling rate than the primary loop, estimates a more up-to-date torque error which is compared to a secondary torque error band, where the secondary torque error band is preferably narrower that the primary torque error band. If the secondary loop determines that the up-to-date torque error has exceeded the secondary torque error band, it sets a null voltage vector, thereby limiting torque ripples.

Abstract: A feed chain (16) has M feed outputs (31) for supplying a synchronous electric machine (14) with M phases. The feed chain comprises: a converter (22) for converting a direct input current into a polyphase alternating current; a storage bank; a detector (30) for detecting a short-circuit outside or inside the electric machine (14), a device (26) for insulating the electric machine (14) from overvoltages and/or overcurrents of the polyphase alternating current, and a controller (28) for controlling the converter (22) and the insulating device (26). The feed chain (16) includes short-circuiting device (27) capable of connecting the M power supply outputs (31) to each other, the controller (28) being capable of commanding the short-circuiting device (27) to perform that operation.

Abstract: For each phase of a controller, a pair of semiconductor switches comprises a high side switch and a low side switch. A direct current voltage bus provides electrical energy to the semiconductor switches at a test voltage level less than a full operational voltage level. A measuring circuit is adapted to measure the direct current bus voltage. A data processor determines that a deficiency in a tested, related semiconductor switch is present if the measured direct current bus voltage decreases or collapses upon activation of a particular semiconductor switch in the same phase of the controller, or if other sequential test results indicate a deficiency. If the deficiency in the related semiconductor switch is present the processor may prevent the voltage supply from providing the full operational voltage to the direct current data bus to prevent damage to the motor or the controller, for example.

Abstract: A motor control system includes: a power supply; a converter; an inverter; an alternating-current motor; and a control unit that drives the motor in any one of sinusoidal PWM control, overmodulation control and rectangular wave control through operation control of the converter and the inverter. The control unit starts step-up operation of the converter when a current vector of motor current of the motor on a d-q coordinate plane becomes a current phase corresponding to motor torque, at which a system loss is equal between before and after starting the step-up operation, while the control unit supplies the direct-current voltage, supplied from the power supply, to the inverter without stepping up the direct-current voltage by the converter and performs the rectangular wave control of the motor in a state where the current phase is an optimal current phase.

Abstract: A carrier frequency setting unit sets a carrier frequency based on a torque command and a motor rotation number of a motor generator. A PWM signal producing unit produces phase modulated waves corresponding to respective phase voltage commands, and produces respective phase PWM signals corresponding to a relationship in magnitude between the respective phase modulated waves and a carrier having the carrier frequency. A PWM center control unit produces a PWM center correction value for variably controlling the PWM center when the carrier frequency is lower than a predetermined frequency, and provides the same to the PWM signal producing unit.

Abstract: Energy efficiency settings for an elevator installation can be determined based on, for example, a start floor for a trip, a destination floor for a trip, user identity information and/or a condition associated with one or more users. In at least some cases, portions of a building (e.g., one or more floors) are associated with one or more energy settings. In further cases, an occupant of a building is associated with one or more elevator energy settings. Some embodiments can be used with an escalator installation.

Abstract: A load drive circuit may include a DC power source configured to provide a DC output voltage for at least one load based on an output voltage of an AC/DC converter, the DC output voltage having a ripple, a variable resistance module connected to the load, a ripple reduction module that generates, based on a reference voltage and a feedback signal from the load, a variable resistance adjusting signal for adjusting the resistance of the variable resistance module so as to reduce a ripple of the load current, wherein the reference voltage is generated based on the DC output voltage, and a reference voltage adjusting module that adjusts the average value of the reference voltage based on the variable resistance adjusting signal, so as to make the average value of the reference voltage approach the average value of the feedback signal as much as possible.

Abstract: An apparatus for controlling a multi-winding rotary machine including an armature formed of a plurality of winding sets. In the apparatus, a command voltage calculator calculates command voltages to be applied to each winding set so as to control currents detected by a current detector to their respectively corresponding command currents. An interfering voltage calculator calculates, for each of the winding sets, interfering voltages proportional to the rotation speed of the rotary machine. An interfering voltage compensator compensates, for each of the winding sets, the command voltages for their respectively corresponding interfering voltages. An operation unit operates a voltage applicator to apply output values of the interfering voltage compensator to each winding set.

Abstract: This invention relates to a method for generating switching signals for inverters using wavelet basis functions as a means to determine switching times, pulse duration, shifting and scale; and to a three phase, six pulse wavelet modulated inverter employing the method as a switching technique.

Abstract: An electrical consumer of an aircraft comprises an electric motor and an inverter for producing an alternating voltage for the electric motor. A method for controlling the electrical consumer comprises determining a rotational frequency for the electric motor. The method also includes establishing whether the rotational frequency leads to oscillations in the input current of the inverter which are below a predefined threshold, the oscillations being produced by the inverter when producing a supply voltage for the electric motor, and changing the rotational frequency if it has been established that the rotational frequency leads to oscillations below the predefined threshold.

Abstract: A motor speed controller controls a motor speed to generate a phase reference pulse; generates a FG pulse per rotary angle of the motor; detects a difference between the number of phase reference pulses and the number of FG pulses for output as an integer number phase difference; detects and measures a time difference between an edge of the phase-reference pulse and an edge of the FG pulse in units of the reference clock for output as a decimal fraction phase difference; adds the integer number phase difference to the decimal fraction phase difference at a predetermined ratio for output as a phase difference; and controls driving of the motor in accordance with the phase difference.

Abstract: A pitch drive circuit that operates in an emergency mode, for a wind or water power plant. The circuit has at least one rectifier unit, at least one DC intermediate circuit, two inverter units and a pitch rotary current motor with motor trains that can be contacted on both sides. A first contact side of the motor trains is connected to a first inverter unit and a second contact side of the motor trains is connected to a second inverter unit. At least one switching element is connected to at least one contact side of the motor trains. In a normal operating mode of a first switching state of the switching element the motor trains can be energized via both inverter units, and in an emergency operating mode of a second switching state of the switching element, the motor trains can be energized via a single inverter unit.

Abstract: A system and method for determining a rotor time constant of an AC induction machine is disclosed. During operation of the induction motor, a flux signal is injected into a rotor flux command so as to generate a time-variant rotor flux. A voltage-current flux observer determines amplitudes of rotor flux variations resulting from the time-variant rotor flux, with the amplitudes of the rotor flux variations comprising an amplitude of a rotor flux variation based on a current model of the voltage-current flux observer and an amplitude of a rotor flux variation based on a combined voltage-current model of the voltage-current flux observer. A rotor time constant of the induction motor is then estimated based on the determined amplitudes of the rotor flux variations.

Abstract: A three-phase AC motor (4) has a configuration in which a q-axis inductance is larger than a d-axis inductance by a predetermined amount or more to allow smoothing of power fluctuations due to the power supply voltage of the AC power source (3).

Abstract: A method for minimizing power losses in an alternating current (AC) machine is provided. The method includes determining a first rotor flux signal based on signals of voltage and current inputs to the AC machine, and extracting a ripple component of the rotor flux signal. The method further includes determining a power compensating value that corresponds to a stored energy value of the AC machine, determining a second rotor flux signal that serves to minimize power losses, and providing the second rotor flux signal to a power inverting unit that adjust accordingly the voltage and current input signals provided to the AC machine.

Abstract: A drive system for an electric motor includes a connection for a battery, and an inverter having an input side connected to an intermediate circuit and an output side having a connection for an electric motor. The intermediate circuit includes a first thyristor connected in parallel with an intermediate circuit capacitance. The drive system may also include a rectifier having an input side connected at the output side of the inverter in parallel with the electric motor, and a second thyristor connected an output side of the rectifier. The first/second thyristor are configured to be activated by a monitor incorporated in or assigned to the drive system. In the event of a malfunction, the input and/or output side of the inverter can be electrically isolated to allow a multiply redundant armature short circuit.

Abstract: A system for identifying magnetizing inductance and rotor resistance of an induction machine comprises an induction machine comprising a rotor and a stator, a DC voltage bus, and a DC-to-AC voltage inverter coupled to the DC voltage bus and to the induction machine. The system also comprises a controller configured to cause the DC-to-AC voltage inverter to apply a square-wave excitation to a plurality of phases of the induction machine, determine a stator resistance of the stator of the induction machine based on the square-wave excitation, and determine a rotor resistance of the rotor of the induction machine based on the square-wave excitation. The controller is also configured to calculate a magnetizing curve for the induction machine based on the stator and rotor resistances and control the induction machine to operate based on the magnetizing curve.

Abstract: An induction motor controller is provided. The induction motor controller includes a first module that derives a commanded stator voltage vector, in a stator flux reference frame, via a rotor flux regulator loop and a torque regulator loop, which process at least partially in the stator flux reference frame. The induction motor controller includes a second module that processes the commanded stator voltage vector to produce AC (alternating current) power for an induction motor.

Abstract: A motor drive circuit includes: an advance angle setting correcting device having a correction reference cycle according to a reference advance angle count value, in which a correction amount is calculated as a ratio of the correction reference cycle to a cycle of a detection signal indicating a detected frequency proportional to a motor rotation speed, and in which an advance angle setting signal is obtained by multiplying the correction amount by a proportionality factor; and an advance angle setting device in which the advance angle correction value is added to the reference advance angle count value thereby outputting an advance angle setting signal, wherein a drive command signal containing a rotation speed information based on a target rotation speed is externally fed, the motor rotation speed is variably controlled in response to the drive command signal, and the detection signal is fed from a rotation speed detecting device.

Abstract: An apparatus and method for controlling the operation of a laundry treating appliance having a rotatable treating chamber for holding laundry and a motor for rotating the treating chamber based on a monitored torque signal from the motor of the laundry treating appliance.

Abstract: A control device for a vehicular power system including an induction motor includes an electronic control unit configured to detect a locked state of the induction motor, calculate a lock-release slip frequency that causes an electric frequency to be outside a lock range, and control the induction motor so that a slip frequency of the induction motor becomes equal to the lock-release slip frequency when the locked state is detected.

Abstract: A method for use in monitoring a synchronous machine includes coupling a power conversion assembly to an electric power source and to a synchronous machine. The synchronous machine includes a plurality of winding inter-turn portions. The method also includes energizing the synchronous machine via the power conversion assembly. The method further includes recording at least one first operational measurement of the power conversion assembly and the synchronous machine. The method also includes calculating a first impedance downstream of the power conversion assembly based on the first operational measurement. The method further includes recording at least one second operational measurement of the power conversion assembly and the synchronous machine. The method also includes calculating a second impedance downstream of the power conversion assembly based on the second operational measurement.

Abstract: A control device for an induction motor that drives a vehicle includes an electronic control unit. The electronic control unit i) controls torque of the induction motor when an inverter that controls supply of electric current to the induction motor is in a locked state, so as to release the inverter from the locked state, ii) determines whether the inverter is in the locked state, iii) controls a slip frequency of the induction motor when it determines that the inverter is in the locked state, and iv) superimposes a frequency that actual torque does not substantially respond, on the slip frequency, so that an electric frequency lies in a region outside a lock region in which the inverter is in the locked state.

Abstract: In a control apparatus for an AC electric motor, a dq axis current feedback control unit 44 and a qn axis current feedback control unit 46 execute a feedback control of higher harmonic components of actual currents id and iq flowing in an AC electric machine 10 to higher harmonic current instruction values ?idkr and ?iqkr. A d axis current instruction value adjusting unit 24 and a q axis current instruction value adjusting unit 26 add the higher harmonic current instruction values ?idkr and ?iqkr to fundamental current instruction values idr and iqr. Ad axis current feedback control unit 32 and a q axis current feedback control unit 34 execute a feedback control of a difference between the actual currents id and iq and the sum of the higher harmonic current instruction values ?idkr, ?iqkr and the fundamental current instruction values idr and iqr into zero.

Abstract: A system and method for limiting engine starting current of a starter motor of an engine is described. In one example, starter motor current is controlled according to vehicle speed. The method may allow vehicle system voltage to remain at a higher level during automatically initiated engine starts.

Abstract: Method and device for operating an asynchronous motor having increased efficiency. According to the invention, ranges for a motor size of the asynchronous motor are specified. In addition, a value of the motor size is calculated depending on at least one measurement value of a measurement parameter during the operation of the asynchronous motor, wherein the respective calculated value of the motor size is allocated to one of the ranges. Furthermore, a control parameter is changed depending on the range to which the calculated motor parameter is allocated to provide an optimised control parameter such that the control parameter is changed beginning from a starting value specified for the respective range of the motor size until a predetermined criterion for a specific motor size is reached. Furthermore, the optimised control parameter is stored as a support point of a continuous optimal characteristic curve for the control parameter depending on the range to which the calculated motor size is allocated.

Abstract: An inverter device of a rotating electrical machine drives a multiphase rotating electrical machine having the variable number of rotations using a switching element provided for each phase. An example of the inverter device of the rotating electrical machine includes: a frequency setting unit for determining and setting a carrier frequency of a carrier signal for use in driving the switching element for each phase depending on the state of each phase of the rotating electrical machine for each specified electrical angle obtained by equally dividing a cycle of an electrical angle; and a signal generation unit for generating a drive signal for drive of the switching element of each phase using the carrier signal of the carrier frequency set for each phase by the frequency setting unit. The carrier frequency of each phase is an integral multiple of the phase voltage frequency at the specified electrical angle.

Abstract: The invention relates to a combined method and device for powering and charging, wherein said device comprises an AC motor (6), a converter (2), storage means (5), and switching means (4) either for enabling the powering of the motor (6) or for enabling the charging of the storage means (5) by the converter (2). The switching means (4) is integrated in the converter (2) and includes at least one H-shaped bridge structure (3) for each phase of the motor (6).

Abstract: In a drive device for a railway vehicle, in which regeneration braking force is increased by adding the output voltage of a voltage adjustment device to a DC power source voltage, operation of the current control device is started prior to the start of the power running operation or the regeneration operation of the inverter device, and the operation of the current control device is stopped later than the stopping of the power running operation or the regeneration operation of the inverter device. Thereby, the current control device is surely operated at least during the operation period of the inverter device, so that the output voltage of the voltage adjustment device is adjusted by the current control device, to thereby prevent the over-discharge of the energy storage device at the time of power running operation or the overcharge of the energy storage device at the time of regeneration operation.

Abstract: A method for monitoring input power to an electronically commutated motor (ECM) is described. The method includes determining, with a processing device, an average input current to the motor, the average input current based on a voltage drop across a shunt resistor in series with the motor, measuring an average input voltage applied to the motor utilizing the processing device, multiplying the average input current by the average voltage to determine an approximate input power, and communicating the average input power to an external interface.

Abstract: A lower limit value setting unit (52) variably sets a lower limit value (Vth) of a target voltage (Vh*) in a range of a voltage that is higher than the maximum value of voltages (Vb1, Vb2) of power storage devices and is not affected by a dead time provided for converters, based on temperatures (Tb1, Tb2) and required electric powers (Pb1*, Pb2*). A maximum value selection unit (53) sets the maximum value among the voltages (Vb1, Vb2) of the power storage devices and required voltages (Vm1*, Vm2*) of motor-generators, as the target voltage. A target voltage limiting unit (54) compares the target voltage with the lower limit value (Vth), and if the target voltage is lower than the lower limit value (Vth), the target voltage limiting unit (54) sets the lower limit value (Vth) as the target voltage (Vh*).

Abstract: A system and method for detecting input phase loss in an adjustable speed drive (ASD) includes an input unit to detect operating data from the ASD. The operating data includes a DC link current of the ASD. The system also includes a state observer that is adapted to receive the operating data from the input unit and extract a DC link capacitor current of the ASD using the DC link current. The system also includes a controller programmed to compare the extracted DC link capacitor current to a predetermined fault range and generate a fault indication of an input phase loss if the extracted DC link capacitor current is within the predefined fault range. The controller is also programmed to calculate an estimated lifespan of the DC link capacitor based on the extracted DC link capacitor current.

Abstract: A motor drive system comprising: an inverter that supplies power to a three-phase motor; and a control unit that controls switching elements of upper and lower arms included in the inverter by switching between supply control of controlling the switching elements so that alternating current is supplied to three phases of the three-phase motor and suspension control of controlling the switching elements so that the supply of current is stopped. The suspension control involves: putting and keeping, in a conduction state, a switching element of at least one upper arm each corresponding to one of one or more phases through which current flows in a direction entering the three-phase motor at a timing at which the supply of current is stopped, and putting and keeping switching elements of rest of the upper arms and switching elements of lower arms in a non-conduction state.

Abstract: A method for minimizing power losses in an alternating current (AC) machine is provided. The method includes determining a first rotor flux signal based on signals of voltage and current inputs to the AC machine, and extracting a ripple component of the rotor flux signal. The method further includes determining a power compensating value that corresponds to a stored energy value of the AC machine, determining a second rotor flux signal that serves to minimize power losses, and providing the second rotor flux signal to a power inverting unit that adjust accordingly the voltage and current input signals provided to the AC machine.

Abstract: A system for identifying magnetizing inductance and rotor resistance of an induction machine comprises an induction machine comprising a rotor and a stator, a DC voltage bus, and a DC-to-AC voltage inverter coupled to the DC voltage bus and to the induction machine. The system also comprises a controller configured to cause the DC-to-AC voltage inverter to apply a square-wave excitation to a plurality of phases of the induction machine, determine a stator resistance of the stator of the induction machine based on the square-wave excitation, and determine a rotor resistance of the rotor of the induction machine based on the square-wave excitation. The controller is also configured to calculate a magnetizing curve for the induction machine based on the stator and rotor resistances and control the induction machine to operate based on the magnetizing curve.

Abstract: A motor drive apparatus that can be used to drive a wide range of brushless motors without any limit to a magnetic pole number of a rotor magnet. One rotational period T of the rotor magnet is obtained, and one period S of the sine wave drive signal according to a mathematical expression of S=T/(n/2). The one period S of the sine wave drive signal is updated at intervals of one period of the output signal from one magnetic pole detecting element among the three magnetic pole detecting elements.

Abstract: A direct-current to three-phase alternating-current inverter system includes a three-phase motor, a plurality of switching elements, an inverter circuit for the three-phase motor, a capacitor, a direct-current power source and a control circuit. The switching elements arranged in the inverter circuit serve as upper and lower arms for the respective three phases of the three-phase motor, respectively. The capacitor is connected in parallel to the respective pairs of the upper and lower arms. The direct-current power source is arranged between the neutral-point of the three-phase motor and the respective lower arms or the respective upper arms. The control circuit controls the switching elements such that at least the switching frequency of one pair of the switching elements for one phase through which the current having the greatest value flows is lower than the switching frequencies of the other pairs of the switching elements for the other phases.

Abstract: The motor position controller inputs a command pulse signal and a desired pulse form setting, and drives a motor based on the command pulse signal. The motor position controller includes a position command generating device configured to generate a position command signal from the command pulse signal in accordance with the inputted desired pulse form setting, a motor controlling part configured to supply power to the motor based on the position command signal, and a first conformity determination device configured to determine the conformity of the desired pulse form setting and the command pulse signal.

Abstract: An apparatus for estimating a parameter of an induction motor is provided. The estimating apparatus receives an output from a current controller and d and q-axis currents in a synchronous reference frame applied to an induction motor, calculates an error of rotor resistance, and obtains a difference between the rotor resistance and nominal rotor resistance to calculate stator resistance therefrom.

Abstract: A sensor detects position data for a rotor of the motor at a first time. A data processor receives the detected position data associated with a first time delay. A sensing circuit senses an analog current at the motor during a second time delay. An analog-to-digital converter converts the analog current to a digital current data during a third time delay. The fourth time delay is detected between actual current reading instant and position reading instant in a data processor. The digital phase current data is transformed into measured direct and quadrature axes control current data based on synchronization or temporal alignment of the position data with the actual measured analog phase current at the starting time by compensating the position data by a sum of the second time delay, the third time delay and the fourth time delay, where the first time delay is subtracted from the sum.

Abstract: An electric power steering apparatus detects, as an abnormal phase, a phase other than a combination of phases whose interphase voltage is of nearly zero volts if a q-axis current is equal to or smaller than a first threshold value though a q-axis voltage is being applied. Alternatively, the electric power steering apparatus calculates a base electric angle at which the q-axis current is equal to or smaller than a third threshold value though the q-axis voltage is being applied, and determines an abnormal phase based on the base electric angle.

Abstract: An automotive electric drive system may include an electric power source, an electric machine, and a DC-DC power converter electrically connected between the electric power source and the electric machine. The DC-DC power converter may include an inductor and a first switch each disposed in a different current path connecting the electric power source and the electric machine. The currents paths may be electrically in parallel.