Abstract: A device for improving efficiency of an induction motor that soft-starts the motor by applying a voltage to the motor that is substantially less than the rated voltage then gradually increasing the voltage while monitoring changes in current drawn by the motor, thereby detecting when maximum efficiency is found. Once maximum efficiency is found, the nominal motor current is found and operating ranges are set. Now, the voltage to the motor is increased/decreased by measuring the phase angle between the voltage and the current to the motor and increasing the voltage when the phase angle is less than a minimum phase angle (determined during soft-start) and decreasing the voltage when the phase angle is greater than or equal to the minimum phase angle as long as the voltage does not fall below a minimum voltage determined during soft-start.

Abstract: Systems and methods are provided for diagnosing stator windings in an electric motor operating under control of a current-regulating control loop. The current-regulating control loop is configured to provide a command voltage to the electric motor. The command voltage comprises a current-regulated voltage based on a difference between a commanded current and a measured current through the stator windings. The method comprises determining a negative sequence component of the command voltage, and identifying a fault condition when a characteristic of the negative sequence component is greater than a threshold value.

Abstract: A multiphase electromagnetic machine may be controlled by controlling currents in one or more phases of the multiphase electromagnetic machine. A control system may be used to determine how much current to deliver to, or extract from, each phase. The control system may use an objective function, subject to one or more constraints, to determine the current. The control system may use position information to determine the objective function, constraints, or both.

Abstract: Generation voltage control or generation torque control is performed as suitable control based on an external command or a load of a generator motor, to thereby prevent a rapid change of a generation torque or excessive power generation. A power converter control apparatus includes: a power conversion unit including a bridge circuit for controlling energization of an armature winding and a field circuit for controlling energization of a field winding; and a control device including B-terminal voltage detection means, field current detection means, generation voltage control means, generation torque control means, and control selection means. The control selection means selects the one of the generation voltage control means and the generation torque control means based on one of a command from an outside and a load of the generator motor.

Abstract: An electric motor drive control apparatus includes a detection angle obtaining section that obtains the detection angle of the resolver; a correction information storage section that stores correction information for correcting the detection angle, in association with a modulation ratio that is a ratio of an effective value of a fundamental wave component of the AC voltage to the system voltage; and a detection angle correcting section that obtains the correction information from the correction information storage section, based on the modulation ratio at the time the detection angle obtaining section obtains the detection.

Abstract: Methods and systems for controlling an electric motor are provided. A signal comprising at least first and second cycles is provided to the electric motor. A first flux value for the electric motor associated with the first cycle of the signal is calculated. A second flux value for the electric motor associated with the second cycle of the signal is calculated based on the first flux value.

Abstract: A method is provided for controlling an induction motor having a rotor. The method includes receiving a torque command; comparing the torque command to a threshold torque value; generating, with a first estimation module, a first estimated rotor resistance when the torque command is less than or equal to the threshold torque value; generating, with a second estimation module, a second estimated rotor resistance when the torque command is greater than the threshold torque value; and generating control signals for the induction motor based on the first estimated rotor resistance or the second estimated rotor resistance.

Abstract: A system and method for controlling an AC motor drive includes a control system programmed with an energy algorithm configured to optimize operation of the motor drive. Specifically, the control system receives input of an initial voltage-frequency command to the AC motor drive, receives a real-time output of the AC motor drive generated according to the initial voltage-frequency command, and determines a real-time value of a motor parameter based on the real-time output of the AC motor drive. The control system also inputs a plurality of modified voltage-frequency commands to the AC motor drive, determines the real-time value of the motor parameter corresponding to each of the plurality of modified voltage-frequency commands, and identifies an optimal value of the motor parameter based on the real-time values of the motor parameter.

Abstract: It is determined which of six continuous sections having different magnitude correlation of signal amplitude of each phase of an input three-phase signal a section is. Predetermined subtraction is performed between respective phases in the section, to obtain a normalized amplitude value normalized in the section, using the subtraction result. The normalized amplitude value is converted to a vector phase for one cycle based on a predetermined phase and output corresponding to the determined section.

Abstract: The method for the automatic adjustment of a protective device includes determining an integral of the square of a motor current over time on the basis of a time motor current profile of an asynchronous motor on a load, after switching on and reversing and deriving a tripping time of the overcurrent release on the basis of the determined integral, the integral, which corresponds to a heating of the asynchronous motor, being related to a multiple of the square of the rated current, and the motor current profile including at least the starting current, the transient and the selected motor rated current.

Abstract: When output voltage V1 of an electric power converter reaches a prescribed voltage V1*ref, a difference between V1 and V1*ref is integrated to correct a commanded torque to ?o* (?*=?o*+??).

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

Abstract: A ram air fan control system includes a ram air fan motor, the ram air fan motor being a pole-change induction motor with at least two pole-count configurations, a ram air fan contactor in operative communication with a first pole-count configuration of the ram air fan motor over a ram air fan conductor bus, a ram air fan power controller in operative communication with the ram air fan contactor, a common contactor in operative communication a second pole-count configuration of the ram air fan motor over a common conductor bus, the common conductor bus being separate and electrically isolated from the ram air fan conductor bus, and a common power controller in operative communication with the common contactor.

Abstract: A sensorless induction motor control device with a function of correcting a slip frequency wherein a slip frequency estimation unit estimates the slip frequency from at least one kind of current flowing through the motor. A voltage command value calculation unit calculates a D-phase voltage command value and a Q-phase voltage command value which are used for controlling a voltage applied to the motor using a Q-phase current command value calculated based on a difference between a speed estimation value, which is calculated using an estimation value of the slip frequency, and an externally supplied speed command value. An ideal voltage command value determination unit determines an ideal voltage command value using the speed command value and the Q-phase current command value. An actual voltage command value calculation unit calculates an actual voltage command value using the D-phase voltage command value and the Q-phase voltage command value.

Abstract: The invention relates to a power supply having two inverters (A, B) in series for powering an electromechanical actuator having an electric motor including a plurality of windings (R1, R2, R3) forming phases, each inverter being connected to its own ground (50; 51) and having a voltage source (U1; U2) having as many arms (A1, A2, A3; B1, B2, B3) as there are windings to be powered, each arm including two controlled switches (5, 6) connected in series, with a point therebetween being provided for connection to one end of one of the windings. According to the invention, each inverter includes an additional arm (A4; B4) having two controlled switches, the two additional arms being interconnected by a bridge (7) that is connected to each of the additional arms at a point that is situated between the switches.

Abstract: A motor driver, including a bridge circuit including a switching element and a diode, connecting with a coil terminal of each phase of a polyphase motor; a modulator modulating a voltage value applied to the coil terminal of each phase such that a minimum voltage value applied thereto is zero; a PWM signal generator generating a PWM signal, based on the voltage value applied to each phase, which is modulated by the modulator; and a switching element drive signal generator generating a switching element drive signal to drive the switching signal, based on the PWM signal generated by the PWM signal generator.

Abstract: A circuit and method of applying a three phase power source to a load such that each phase is applied to the load in a manner, such as a predetermined sequence, so as to reduce the electromagnetic interference (EMI) and heat generated in the switching devices during the application and removal of each phase to the load.

Abstract: An electric motor drive device has an inverter adjusting the voltage applied to an AC electric motor so as to drive the AC electric motor, a capacitor which is charged by a current supplied from a DC power supply supplying DC voltage between a neutral point at which a plurality of coils of the AC electric motor are connected and a positive rail or negative rail of an inverter and passing through the inverter, and a control circuit controlling the inverter so that the AC electric motor turns at a designated speed. Further, the control circuit selectively uses field weakening control and voltage boosting control for control of the inverter according to the conditions of the induced voltage generated at the AC electric motor, DC power supply, and voltage of the capacitor.

Abstract: A single-phase AC motor control circuit for a dryer, including a starting control unit, a first drive circuit, a bidirectional triode thyristor BCR1, a second drive circuit, and a bidirectional triode thyristor BCR2. The bidirectional triode thyristor BCR1 is serially connected to a motor starting winding, and a starting capacitor, and then to a utility power AC input. The starting control unit is connected to a control end of the bidirectional triode thyristor BCR1 via the first drive circuit. The bidirectional triode thyristor BCR2 is serially connected to an electrically heated strip, and then to the utility power AC input. The starting control unit is connected to a control end of the bidirectional triode thyristor BCR2 via the second drive circuit. The first drive circuit is interlocked with the second drive circuit.

Abstract: An automotive drive system and methods for making the same are provided. The system includes a three-phase motor and an inverter module. The three-phase motor includes a first set of windings each having a first magnetic polarity; and a second set of windings each having a second magnetic polarity that is opposite the first magnetic polarity. The first set of windings being electrically isolated from the second set of windings. The inverter module includes a first set of phase legs and a second set of phase legs. Each one of the first set of phase legs is coupled to a corresponding phase of the first set of windings, and each one of the second set of phase legs is coupled to a corresponding phase of the second set of windings.

Abstract: A motor drive system using a current source inverter (CSI) for providing the main power and an active filter for providing the reactive power and harmonics is disclosed. The CSI can be a load-commutated inverter (LCI) build using silicon-controlled rectifiers (SCRs), while the active filter can be based on a voltage-controlled inverter. An LCI circuit comprising of SCRs, wherein CSI is autosequentially turned off is provided. In other words, the negative voltage for turning the SCR off is not load dependent. A control scheme for operating the motor drive system through proper control of the SCRs in the LCI circuit is also provided. As presented, the motor drive system is able to feed medium to high voltage motors using a simple circuit, such that low-frequency torque pulsations are eliminated.

Abstract: A power converter includes: a determination section which, prior to an actual operation, determines presence/absence of a common mode filter connected to a line for supplying power to a motor, switching elements being driven with a predetermined PWM on/off drive signal corresponding to a carrier frequency prior to the actual operation; and a PWM control method changing/setting section which, during the actual operation, changes and sets a PWM control method in accordance with a result of the determination of the presence/absence of the common mode filter.

Abstract: A method for fault diagnosis for a rotor of an electric motor, the electric motor also having a stator, includes the steps of generating, via a processor, a measured motor current for the stator, determining, via the processor, a resolver angle of the rotor, determining, via the processor, a flux angle of the rotor, calculating, via the processor, a transformation angle using the resolver angle and the flux angle, conducting, via the processor, a transformation of the motor current using the transformation angle, and identifying, via the processor, a fault condition based on the transformation.

Abstract: To further improve the stability of drive control for the start period of a motor without complicating a circuit configuration. During the period in which the rotational speed of a rotor does not reach the rotational speed capable of locking a PLL circuit, a drive control method of two-phase mode in which a start current is supplied by two energizing patterns is used. In energizing pattern A, a current is caused to flow in a motor winding in the direction from U to W and in the direction from V to W at the same time. In energizing pattern B, a current is caused to flow in the motor winding in the direction from W to U and in the direction from W to V at the same time. A potential difference Vu-v between a U phase and a V phase in which the phase and magnitude of voltage drop due to inductance are equal is detected. Based on the detected potential difference Vu-v, a magnetic flux estimation signal ?u-v is calculated by an integrator.

Abstract: The controller controls a spindle connected to an induction motor via a belt by controlling the rotational velocity of the induction motor. The spindle has an encoder attached thereto for detecting the position of the spindle, but the induction motor does not have a velocity detector attached thereto. The velocity of the induction motor is estimated from the spindle velocity obtained from output of the encoder, and slip of the belt is detected based on the estimated velocity of the induction motor. When occurrence of slip of the belt is detected, the estimated velocity of the induction motor will not be used for the control of the induction motor.

Abstract: [Problem] In a pseudo-current source inverter which drives a motor at a high speed, a current phase adjustment is assured and facilitated to perform a field-weakening control or suppress a terminal voltage saturation at a time of the high-speed motor drive. [Means For Solving Problem] A phase advance correction is carried out for a magnetic flux phase information from which a 120 degree conduction pattern is obtained with a motor terminal voltage as a reference phase. The phase advance correction includes the correction of differentiating the terminal voltage detection signals of the motor, the adjustment of enlarging the phase advance correction quantity in a case where the motor load current is large, and delays the gate signals of the 120 degree conduction pattern in accordance with the speed estimation value through a delay counter and carries out the phase advance correction as the rising edge timing of the subsequent gate signal at the subsequent step phase.

Abstract: A motor rotational position detecting method detects the magnetic pole position of each phase of a three-phase AC servomotor, generates a three-phase square wave signal having a phase difference of 120 degrees, allocates data on the rotational position of a motor shaft to the edge of each square wave signal, calculates the rotational speed of the motor on the basis of the elapsed time from the previous edge detection point to this time edge detection point, and estimates the rotational position of the motor shaft at a certain period and outputs it on the basis of the rotational speed of the motor and the rotational position allocated to this time edge in the rotational section from this time edge detection point to the next edge detection point. As a result, a detection mechanism can be constructed with a small installation space and at low cost and the output of a high-resolution encoder can be obtained in a pseudo manner.

Abstract: A rotating electromechanical machine has a rotor having at least one current-carrying winding and at least one rotor-mounted sensor configured to sense a machine property or parameter during machine operation. Rotor-mounted circuitry dynamically modifies at least one property of the current-carrying winding during machine operation in response to the sensed machine property or parameter.

Abstract: The present invention relates to an energy-saving system for three-phase induction motors and is based on the principle of variable voltage control at constant speed. It is composed of a microprocessor, exampling circuit, sensing circuit, acquiring circuit, firing circuit, and AC to AC converter. The system is to automatically adjust the voltage to the induction motor with the variation in the motor load, in order to obtain high operating power factor and efficiency. The system will result in considerable energy-savings when a three-phase induction motor runs under constant light-load or variable-load with low duty ratio.

Abstract: The invention relates to a method for positional recognition of a rotor of an electronically commutated electric machine, in particular an electric motor, in which a zero crossover of a voltage induced in a coil section of the rotor or stator is used for positional recognition. According to the invention, to determine the zero crossover the coil section is briefly powered down. A rotor/stator is used, comprising at least two coil sections, one of which has a lower inductance relative to the other one, and preferably only the coil section with the lower inductance is used for the positional recognition.

Abstract: At least two asynchronous AC induction electrical machines in series connection with the power source are respectively made with the main winding and control winding for operating the electrical machines, wherein the individually driven loading operations of the two electrical machines in cross-interlockingly series connection being series connected with the power source are led by the changes of individual electrical machine driving loading statuses to appear variable impedance operation so as to change the end voltage ratio between individual electrical machines in cross-interlockingly series connections.

Abstract: In a method for field-oriented operation to zero speed of an encoder-less asynchronous machine, wherein the associated field-oriented regulation device has a monitor with a machine model and rotation-speed adaptation, a model flux and a model current are calculated from a calculated actuating voltage and an adapted rotation speed, from which, in conjunction with a determined machine current, a complex difference is calculated. Also calculated is a model slip rotation speed as a function of the model flux and the model current, which is then scaled. The adapted rotation speed is then superimposed, and the sum is used as the rotation speed actual value which supplied to a rotation-speed regulator. An asynchronous machine without an encoder can therefore be operated to zero speed on a field-oriented basis.

Abstract: A motor controller for controlling at least one electric motor has an operating signal generator for generating an operating control signal for the at least one electric motor and also a sound signal generator for generating a sound control signal. A mixer superimposes the sound control signal on the operating control signal in order to obtain a control signal for the at least one electric motor. It is then possible to dispense with loudspeakers and the like in the appliance which contains an electric motor with such a motor controller in order to output, for example, signal tones which indicate an operating state of the appliance to the user.

Abstract: Methods, system and apparatus are provided for sensorless control of a vector controlled motor drive system that includes an electric motor used to drive an auxiliary oil pump.

Abstract: An AC machine control system for an AC machine (motor, generator, transformer, etc.) having open-ended windings, the control system comprising a drive circuit configured to transfer AC power between a first set of voltages and each end of the open-ended windings without the use of a substantial energy storage device, while eliminating common mode voltage and/or injecting zero sequence voltages.

Abstract: An active reactive induction motor is provided. The motor comprises two sets of three-phase windings. One set of windings carries the active power and is called the power windings. The second set of windings carries the reactive power and is called the flux windings. The power windings carrying the active power provides more power to the induction motor than the flux windings carrying the reactive power. A driver circuit for driving the active reactive induction motor and the corresponding modes of operation is also provided.

Abstract: The present invention relates to a motor controller of an air conditioner, including a converter for converting a commercial AC power into a DC power, an inverter including a plurality of switching elements, the inverter receiving the DC power, converting the DC power into an AC power through a switching operation and driving a three-phase motor, a gate driver for controlling the switching operation of the switching elements, and a plurality of voltage drop units connected between the converter and the gate driver, the voltage drop units dropping the DC power and supplying driving voltages for an operation of the switching elements. Accordingly, circuit elements within a controller can be protected.

Abstract: A motor control apparatus includes a step-up/down converter and an inverter. The converter includes a coil, MOSFETs, capacitors and a control circuit. The control circuit turns on the MOSFET in the high potential side, while tuning off the MOSFET in the low potential side. After a predetermined time, the control circuit turns off the MOSFET in the high potential side and then turns on the MOSFET in the low potential side. It is checked whether the MOSFET, which is switched in the step-down operation, is normal or abnormal based on the voltages of the capacitors. The capacitors produce specific changes in the respective voltages in correspondence to the check result. Thus, the abnormality of the MOSFET can be determined based on the changes.

Abstract: An inverter control apparatus includes: a state estimator that calculates an estimated current vector and an estimated magnetic flux vector from a motor command voltage vector, a detected current vector, and a motor parameter; a correction voltage calculator that calculates a correction voltage vector on the basis of a current error between the detected current vector and the estimated current vector; and a correction voltage unit that adds the correction voltage vector to the motor command voltage vector.

Abstract: An alternating-current motor control apparatus includes a stator frequency computing unit configured to compute a stator frequency of a motor magnetic flux; a torque error computing unit configured to compute a torque error by using the motor magnetic flux, an estimated current, and a motor current; and a speed estimator configured to estimate a speed of the alternating-current motor by using the stator frequency and the torque error. The speed estimator includes a proportional controller configured to reduce the torque error to zero, and an adaptive filter configured to eliminate a high-frequency component of the torque error.

Abstract: A system and method are provided for correction of parameters used in determination of stator turn faults of an induction motor. An embodiment may include determining a residual impedance and/or a residual voltage of the motor, and correcting a normalized cross-coupled impedance based on the residual impedance and residual voltage. Additional embodiments may include measuring an operating temperature of the motor and determining a negative sequence impedance of the motor based on the temperature. Another embodiment may include measuring voltages and currents of the motor and determining phasors for the voltages and currents using compensation for variations from a nominal frequency of the motor.

Abstract: A system and method for identifying turn faults in a stator of a motor are provided. The method includes determining a normalized cross-coupled impedance from the symmetrical components of measured voltages and currents of the motor. Additionally, the normalized cross-coupled impedance may be normalized to a negative sequence impedance. The negative sequence impedance may be determined through a regression analysis using parameters of the motor, such as line-to-line voltage, horsepower, and number of poles. A system is provided that includes a device having a memory and processor configured to determine a normalized cross-coupled impedance, compare the normalized cross-coupled impedance to one or more thresholds, and trigger and alarm and/or trip the motor.

Abstract: A control and power device for a rotating electrical machine comprising a management circuit and a power circuit including a number of power transistors and driver circuits associated with the power transistors. The device provides connection between the management circuit and the driver circuits for switching on the driver circuits and transmitting at least one transit potential between the management circuit and the driver circuits. The invention is applicable to alternator-starter.

Abstract: A motor magnetic pole position detecting device includes a detection current command generation unit generating a detection AC current command, a current detection section detecting a current flowing into the motor, a coordinate conversion unit vector-converting the current detected by the current detection section into an excitation component and a torque component both represented by a d-q orthogonal coordinate system based on a phase angle obtained at any rotational frequency, a current control unit delivering a voltage command to current-control the motor based on the detection current command and the current converted by the coordinate conversion unit, an inductance calculation unit calculating motor inductance based on the voltage command and the current converted by the coordinate conversion unit, and a magnetic pole position detection section calculating a frequency and phase of the inductance calculated by the inductance calculation unit, converting the inductance phase into a motor magnetic pole pos

Abstract: A system and method are provided for constant loading in AC power applications where at least one turn-on point of at least one half cycle of a modulating sine wave is randomly selected; at least one turn-off point is determined; and at least one slice located between the at least one turn-on point and turn-off point is removed. The slices may be removed by utilizing insulated gate bipolar transistors or field effect transistors.

Abstract: An electronic relay for single phase induction motor, the electronic relay including a triac located between a start winding and a start capacitor of the single phase induction motor to control current flow of the start winding and an induced voltage detection circuit to detect an induced voltage of the start winding proportional to an angular velocity of the motor. The electronic relay is adapted to detect a zero-point voltage of a motor line voltage before start of the motor and to calculate an acceleration torque during start of the motor. The electronic relay is programmed to turn on the triac when the zero-point voltage of the motor line is detected and to turn off the triac when the acceleration torque begins decreasing.

Abstract: A controller continually updates rotor time constant estimation of an induction machine by interrogating the induction machine with a small signal oscillation and monitoring the response. The small signal oscillation is injected onto the d-axis current command signal, and is generated at a frequency that represents the most recent estimate of the rotor time constant (i.e., rotor time constant equal the inverse of the frequency). The controller monitors rotor flux generated in response to the small signal oscillation, and updates the most recent estimate of the rotor time constant based on the monitored rotor flux. This process is repeated continuously to allow for the continuous updating of the rotor time constant.

Abstract: An electric motor drive system having current detecting sections for detecting the currents flowing into electric motors, speed variation calculating sections for calculating the speed variation estimating values for the electric motors in accordance with the motor currents detected by the current detecting sections and the current command values for the motors corresponding to the detected currents and a speed uniformizing voltage compensating section for delivering the values that serve to compensate the amplitudes of the voltages applied to the electric motors in such a manner that the speed variation estimating values calculated by the speed variation calculating sections become equal to a predetermined value.

Abstract: A control system aims at converting, via a switching circuit, a direct current voltage into an alternating current voltage to be applied to multiphase windings of a multiphase rotary machine to thereby control rotation of the multiphase rotary machine. In the control system, a command voltage determiner determines a command voltage value for an alternating current voltage to be applied to the multiphase windings based on a zero crossing of a line-to-line current and a zero crossing of the amount of change in the line-to-line current. A driving unit drives the switching circuit on and off based on the determined command voltage value to thereby modulate the direct current voltage to the alternating current voltage to be applied to the multiphase windings.

Abstract: In a calculation for estimating axis error in a permanent magnet motor, a d-axis commanded voltage value is added to the product of three signals, which are a q-axis detected current value or commanded current value, an inductance value, and an estimated speed value, and then the resulting value is divided by the product of a commanded speed value ?r* and induced voltage constant Ke* or an arctangent calculation is performed in the same way, instead of using a resistance setting.