Abstract: A solid state reversing AC motor starter that employs a DC power source and a power bridge employing insulated gate bipolar transistors that provide an ungrounded three phase AC output. The AC output is connected to the power input of the motor starter, which requires simultaneous RUN and Directional Commands to initiate valve actuation.

Abstract: A compressor is operable to compress refrigerant at a variable operation frequency. According to a method of controlling the compressor, the compressor starts operating, and just after that, the compressor operates at a first frequency for a first period of time. Just after that, the compressor operates at a second frequency lower than the first frequency for a second period of time longer than the first period, and after that, the compressor operates at an ordinary operation. This method does not cause the compressor to generate an abnormal noise or obstruction to lubrication.

Abstract: A method for controlling an inverter uses sequences of predetermined states where each state uniquely corresponding to a set of control signals provided to the inverter that is coupled to a motor. The method includes repeatedly applying a first center null timing sequence of the states while monitoring a zero crossing condition and then changing the repeated application of the first center null timing sequence of the states into a repeated application of a second center null timing sequence of states when the monitoring detects a zero crossing condition. The repeated application of the first center null timing sequence sequentially provides the inverter with a first predetermined sequence of sets of control signals. The monitoring of a zero crossing condition monitors for a zero crossing condition in an electrical current flowing between the inverter and a terminal of the motor. The second center null timing sequence defines a second predetermined sequence of sets of control signals.

Abstract: A frequency converter for outputting a power to drive a motor, having: an inverter unit for inverting a d.c. power to an a.c. power; a control unit for controlling the inverter unit; and a housing for supporting at least the inverter unit and control unit, wherein a rise time change unit is provided in the housing, the rise time change unit changes a rise time of a waveform of a voltage output from the inverter unit.

Abstract: An apparatus controlling a velocity of a motor having a rotor, includes a sensing velocity calculator sensing a rotation velocity of the motor, and calculating a sensing velocity on the basis of the sensed rotation velocity of the motor; a velocity estimator estimating an estimation velocity of the motor based on an information about a position error of the rotor; and a reference velocity calculator dividing an overall velocity period of the motor into a plurality of unit velocity periods based on a command velocity for controlling the rotation velocity of the motor, calculating a sum of the sensing velocity, the estimation velocity, and the command velocity after multiplying at least one of the sensing velocity, the estimation velocity, and the command velocity by a predetermined weight, and outputting the sum as a reference estimation velocity of the motor.

Abstract: A control device controlling a motor-driven four wheel drive vehicle, where either of front wheels and rear wheels are driven by an engine and the others are driven by an AC motor, is provided with an electric power generator driven by an engine to generate first three-phase AC power, a rectifier rectifying the first three-phase AC power, generated by the electric power generator, to second DC power and supplying the second DC power to a neutral point of the AC motor; and a first step-up and step-down inverter stepping up and converting the second DC power, supplied through the neutral point, to third three-phase AC power. The AC motor is rotationally driven by application of the third three-phase AC power from the first step-up and step-down inverter.

Abstract: Certain exemplary embodiments can comprise a system comprising an electric drive system for a machine. The system can comprise a rectifier adapted to convert AC power from an alternator to DC power. The system can comprise an inverter adapted to receive DC power from the rectifier and provide power to a traction motor and/or auxiliary devices. Certain exemplary embodiments can comprise a system and method for dissipating excess energy from a machine.

Abstract: A system and method for controlling an inverter of a motor control unit includes a controller having a user interface configured to allow user selection of a waveform increment value or a waveform amplitude threshold. The controller also includes an integrator configured to receive the waveform increment value and generate a signal at least based on the waveform increment value. A logic circuit is configured to monitor the signal and reset the integrator when the signal reaches the waveform amplitude threshold to generate a waveform having a frequency-independent amplitude. A comparator compares the waveform to a modulating signal to trigger gating pulses delivered to an inverter to drive an associated motor.

Abstract: The invention provides a motor for a brushless DC motor, which has small torque ripple even if a trapezoidal wave current is supplied and has a small size and reduced motor noise, and a drive control device for the motor as well as an electric power steering apparatus using the motor and the drive control device. Respective phase current command values are calculated on the basis of vector control. Pseudo-vector control for controlling respective phases separately is used as current feedback control.

Abstract: A plurality of parameters of a Permanent Magnet Synchronous Motor (PMSM) is determined by a motor controller for differentiating between a plurality of PMSMs. This is achieved by first applying regulated DC motor currents at a commanded fixed rotor angle and measuring a quadrature voltage; parking the PMSM at standstill, Then, after selecting an initial set of controller parameters; applying the quadrature voltage equal to zero and measuring a time constant. Then, accelerating the PMSM with a constant torque up to a preset target speed and measuring a total acceleration time taccelerate until the preset target speed ?target is reached. After regulating a stator current at 0 value, measuring the quadrature voltage and a freewheeling motor speed ?freewheel immediately after applying the 0 stator current; and calculating an electrical constant KE of the PMSM; a load inertia J; and a set of parameters for the controller.

Abstract: A motor driving apparatus includes an inverter circuit for converting an output of a rectifier circuit connected to a single-phase AC power supply into a driving voltage, and outputting the driving voltage to a brushless motor, and an inverter control unit for controlling the amplitude value of the voltage outputted from the inverter to the brushless motor so as to minimize a difference between a command rpm indicated by an external command signal and an actual rpm derived from an estimated phase of the rotor, wherein the command rpm is set to an rpm outside a predetermined range of rpms.

Abstract: Certain exemplary embodiments can comprise a system comprising an electric drive system for a machine. The system can comprise a rectifier adapted to convert AC power from an alternator to DC power. The system can comprise an inverter adapted to receive DC power from the rectifier and provide power to a traction motor and/or auxiliary devices. Certain exemplary embodiments can comprise a system and method for dissipating excess energy from a machine.

Abstract: A motor driving apparatus for driving a motor includes a single-phase rectifier circuit having an input connected to a single-phase AC power supply, an inverter circuit that is connected to the single-phase rectifier circuit and applies a current and a voltage to the motor, and an inverter control unit for controlling the inverter circuit. The inverter control unit controls the current applied to the motor, i.e., the output of the inverter circuit, so that the inverter input voltage becomes equal to the absolute value of the voltage of the single-phase AC power supply.

Abstract: In a method of generating pulse-width modulated waveform, the cycle of a carrier wave for the waveform is determined together with a first dead time value and a second dead time value both of which are set in a plurality of up-down counters, respectively. Using the plurality of the up-down counters is effective to assign individual dead times to upper and lower arms and to linearly control a PWM duty from 0% to 100%.

Abstract: A motor apparatus is constructed to compensate for a delay in operation of the motor apparatus, so that the efficiency is improved and noise is reduced over a broad motor rpm range by driving the motor at the optimum timing.

Abstract: A DC offset compensation system and method significantly reduce a DC offset voltage in the voltage feedback loop of an AC motor drive control system. A control voltage error signal is demodulated and filtered and applied to the closed loop voltage feedback signals to compensate for DC offset voltages in the closed loop voltage feedback. A frequency discriminator tuned to the fundamental motor frequency improves the precision of the DC offset detection. A startup flux DC offset compensation operates to eliminate initial startup flux DC offset. Motor flux compensation is improved through a variable flux filter time constant.

Abstract: A circuit for protecting against controller failure wherein the controller provides control signals for controlling a DC to AC inverter fed by a DC bus and driving a permanent magnet motor, the circuit comprising a first circuit for monitoring the DC bus voltage and, in the event the DC bus voltage exceeds a first threshold due to a counter EMF generated by the motor, for producing a signal to the controller to provide a switch state to the inverter whereby the counter EMF is dissipated substantially in a motor circuit resistance of the permanent magnet motor as a result of a short circuit condition provided by the switch state of the inverter, thereby preventing the DC bus voltage of the inverter from exceeding the first threshold and causing the permanent magnet motor speed to be reduced.

Abstract: A frequency converter for outputting a power to drive a motor, having: an inverter unit for inverting a d.c. power to an a.c. power; a control unit for controlling the inverter unit; and a housing for supporting at least the inverter unit and control unit, wherein a rise time change unit is provided in the housing, the rise time change unit changes a rise time of a waveform of a voltage output from the inverter unit.

Abstract: An electronic drive for vector control of an induction motor controls slip and operating frequency in response to changes in stator voltage. The drive includes a torque control loop, a flux control loop and a frequency control loop. The control is based on a commanded stator current that is resolved into a torque-producing, or q-axis, current component and a flux-producing, or d-axis, current component that are in quadrature. The frequency control loop includes slip control in which a slip frequency command is produces based on a value for the leakage inductance of the motor. The leakage inductance value dynamically varies as a function of the q-axis current reference command.

Abstract: A controller for a variable frequency drive monitors electrical power from a variable frequency drive motor while a brake is maintaining a load driven or moved by the motor without requiring additional feedback components of a closed loop configuration. If excess electrical power is being generated by the motor, an undesirable condition in the brake is indicated. Support or maintenance of the load is assumed by the motor in that event. Appropriate alarms or indicators are also activated.

Abstract: A system for controlling a permanent magnet synchronous motor calculates fundamental a d-axis (or q-axis) voltage command based on a difference between a d-axis (or q-axis) current command and a d-axis (or q-axis) current feedback signal, calculates a harmonic suppression d-axis (or q-axis) voltage command used to suppress at least one higher-order harmonic current component included in a harmonic current component which is calculated based on the differences between the current feedback signals and the current commands, and calculates a d-axis (or q-axis) voltage command by adding the fundamental d-axis (or q-axis) voltage command and the harmonic suppression d-axis (or q-axis) voltage command. The d-axis and q-axis voltage commands are transformed into three-phase voltage commands, which are converted into a drive voltage for driving the permanent magnet synchronous motor. As a result, the harmonic current components are significantly suppressed and the motor's overall performance is improved.

Abstract: An electronic control unit for producing a sufficiently boosted voltage even when a supply voltage becomes high includes an inverter that drives switching elements and converts a DC voltage into an AC voltage, and booster means which boosts a DC voltage that is input into a voltage to lie within a voltage range in which a voltage necessary for driving the switching elements is a lower-limit value and a maximum boosted voltage is an upper-limit value, and outputs the boosted voltage to the inverter.

Abstract: A technique for reconstructing phase currents based on measurements of a DC bus current. Non-observable regions of DC bus current samples to reconstruct phase currents are reduced in size by using two phase space vector modulation. The non-observable regions can be further reduced by omitting deadtime insertions for switch actuations when output current is higher than a given threshold. Voltage command vectors in non-observable areas can be constructed by two time averaged vectors one of which is constructed to obtain an observable DC bus current reflecting motor phase current. The additive vectors have the same combined time average value as that of the voltage command vector in order to preserve volt-seconds. Current samples may also be averaged to provide a more accurate reconstruction of phase current. Current samples are time delayed to avoid transients for more accurate readings.

Abstract: A motor control device that can reduce electrical noise is provided. A motor control device includes an inverter, a current controller, a high frequency wave superpositioner, and a high frequency wave setter. An inverter applies a current to the motor. A current controller outputs a voltage to the inverter according to a current applied to the motor from the inverter. A high frequency wave superpositioner applies a high frequency wave to the voltage from the current controller as a superpositioned wave to infer a position of a rotor in the motor. A high frequency wave setter varies at least one characteristic of the superpositioned wave applied by the high frequency wave superpositioner.

Abstract: A power control apparatus includes an inverter giving a rectangular waveform drive signal to an induction motor, an inverter voltage controlling section controlling an output voltage of the inverter, a converter boosting a voltage supplied to the inverter, a converter voltage controlling section controlling an output voltage of the converter, and a control signal generating section that controls the inverter voltage controlling section in a low-rotational speed region and controls the converter voltage controlling section in a high-rotational speed region.

Abstract: A method of providing ride-through capability in a chiller/refrigeration system employs a variable speed drive with an active converter stage, a DC link stage and an inverter stage for providing variable frequency and voltage to power at least one motor. An induction motor is coupled to the output of the inverter stage for driving a compressor in the chiller/refrigeration system. The ride-through method comprises operating the active converter to regulate the DC link voltage of the DC link stage to a predetermined voltage level until the current through the active converter equals a predetermined current limit, then transferring regulation of the DC link to the inverter upon reaching the current limit of the converter. The compressor is unloaded, and the power flow through the inverter is reversed to maintain the voltage level of the DC link stage.

Abstract: A speed control apparatus having a high frequency generator for superposing a high frequency signal on an estimated magnetic flux axis. A high frequency component extractor extracts an error signal of a magnetic flux position from a voltage or current detection signal having the same frequency component as a frequency component of the high frequency signal. A magnetic flux observer estimates a magnitude and a position of a magnetic flux. A first adaptive regulator adaptively regulates an error signal on a high frequency superposing side. A second adaptive regulator adaptively regulates an error signal on a magnetic flux observer side. A hybrid device switches the first adaptive regulator at a very low speed, the first and second adaptive regulators at a low speed and the second adaptive regulator at a high speed. A speed estimator estimates a speed from an output of the hybrid device.

Abstract: In a control apparatus for a rotating machine, an integration unit integrates a primary angular frequency based on an angular velocity command and computes phase, a power converting unit applies three-phase voltages to the rotating machine according to three-phase voltage commands, a current detecting unit detects three-phase currents flowing through to the rotating machine, a coordinate converting unit converts the currents detected by the current detecting unit into currents on rotating two-axis coordinates based on the phase output by the integration unit and converts voltage commands on the rotating two-axis coordinates into the three-phase voltage commands, and a voltage command computing unit computes the voltage commands based on the absolute value of deviations of the primary angular frequency and the current components along each of the rotating two-axis coordinates.

Abstract: A three-phase spindle motor has three terminals each driven with pulse width modulated signals. Rotation of the motor is controlled by iteratively measuring an electrical period of the motor, determining a rotational position of the motor, and synchronizing the sinusoidal pulse width modulation of the spindle motor with the measured electrical period. The electrical period of the motor is measured by detecting zero crossings in the a back electromotive force induced at a first terminal of the motor and determining the time between successive zero crossings. The rotation position of the motor is determined based upon the last measured electrical period and a location of last detected zero crossing. The zero crossings are detected by selecting a time window during which the back electromotive force signal is sensed for zero crossings. The time window is selected as a function of the last measured electrical period and the rotational position of the motor.

Abstract: A system for controlling a motor comprising: a voltage source; a motor in operable communication with an inverter, the motor responsive to a command signal from the inverter, the inverter is in operable communication with the voltage source and a controller. The inverter includes a plurality of switching devices configured to receive a command from a controller and generate a voltage command to the motor. The system also includes a voltage sensor for detecting a voltage of the voltage command to the motor at a selected instance; and a controller in operable communication with the inverter and the voltage sensor. The controller configured to provide a command to the inverter responsive to the voltage of the voltage command to the motor at a selected instance.

Abstract: An electric motor control apparatus of this invention estimates changes in temperature of a semiconductor device to compute temperature change amplitude 108 based on an output current signal 105 computed from a current flowing through the semiconductor device of a switching circuit 5, an operating frequency signal and a carrier frequency signal by a temperature change estimation part 11, and makes conversion into the number of power cycles 110 corresponding to the temperature change amplitude 108 from power cycle curve data stored in a power cycle curve data storage part 14 and computes a thermal stress signal 111 by a thermal stress computation part 13, and does life estimation of the semiconductor device based on the thermal stress signal 111 and produces an output to a display part 16 as a life estimation result signal 112 by a life estimation part 15a.

Abstract: A shutter mechanism includes a drum (2), a stepping motor (5), a driver (20), a microcomputer (10), a memory (16), and a load magnitude detection circuit (30) that detects the magnitude of the load on the stepping motor (5) when an object such as a shutter (3) is either wound or unwound from the drum (2). The microcomputer (10) can set the upper and lower limit stopping positions of the shutter (3) by resetting the number of command pulses stored in the memory (16) when the load magnitude detection circuit (30) detects an increase in the load at the stepping motor (5), and storing the number of command pulses output to that point from the memory (16) when the load magnitude detection circuit (30) next detects an increase in the load at the stepping motor (5) after the outputting of the command pulses is next restarted.

Abstract: An electric motor car controller includes a voltage detector for detecting the voltage across a filter capacitor, an energy amount calculator for calculating the amount of energy of the filter capacitor from the output of the voltage detector, a frequency band component detector for extracting a given frequency band component included in the amount of energy, a frequency band component coefficient unit for multiplying the frequency band component by a coefficient and outputting a q-axis current command correcting value, and a q-axis current command correcting value adder for adding a q-axis current command correcting value to the q-axis current command value to correct the q-axis current command value.

Abstract: Each of the phases of coil in an armature winding of a dynamoelectric machine is constructed so as to have six turns, an inverter has a plurality of element-diode sets, each element-diode set including a pair of switching elements connected in series and diodes connected in parallel to the switching elements, connection points of the switching elements connected in series are connected to the dynamoelectric machine, a control apparatus controls the inverter such that the dynamoelectric machine is driven by supplying electric power from a first battery to the dynamoelectric machine during starting of an engine, and alternator mode electric power generation is performed by the dynamoelectric machine at least in a normal rotational speed region of the engine.

Abstract: The motor driver having a plurality of output circuits each having two switching elements connected in series includes: a phase switch circuit for putting a switching element on one side of one output circuit among the plurality of output circuits in the ON state during a time period corresponding to a predetermined electrical angle, and performing switching operation for switching elements on the other side of plural output circuits among the remaining output circuits; and a conduction period control section. The conduction period control section generates a signal for controlling the switching operation. Specifically, when the number of times of switching operation performed during the time period corresponding to the predetermined electrical angle is equal to or less than a predetermined value, a switching element corresponding to a phase, for which the magnitude of the current should be decreased, is turned OFF in the time period corresponding to the next predetermined electrical angle.

Abstract: A motor control system for use in heating, ventilation and air conditioning applications including a blower and a motor coupled to drive the blower, an inverter coupled to provide energization to the motor, a relay capable of coupling the motor to the output of the inverter or to line power, and a controller providing signals to control the output of the inverter, where, upon startup and transfer of the motor from the line to the inverter, the output of the inverter is controlled by the inverter to provide for an enhanced startup or transfer.

Abstract: An independent back memory module is disclosed that is permanently installed at a security gate installation. The memory module has a nonvolatile memory and it is positioned within the system so that it automatically has a communication link with any gate controller installed. The memory module records a history of the operation of the system. The memory module retains operational information regarding the system and information identifying the gate controller, gate controller board and the setup of the particular installation. The memory module also retains information regarding changes made in the setup of the system. Whenever a new gate controller board is installed information in the memory module is transmitted to the new controller board.

Abstract: A driving apparatus of a three-phase induction motor includes: a three-phase power supply unit for supplying three-phase power; a rectifier for rectifying the three phase voltage supplied from the three phase power supply unit; a voltage reducing unit for reducing a DC voltage generated from the rectifier and outputting a stabilized DC voltage; and an inverter unit for varying the DC voltage outputted from the voltage reducing unit to a three-phase AC voltage and driving a three-phase induction motor. A power-factor degradation generated during supplying a DC voltage to the inverter to drive the three-phase induction motor is prevented, a harmonic wave is removed, and because a high-priced inverter component is not necessary, its relevant expense is reduced.

Abstract: A method and a device for realizing an effective value of a quantity to be varied in an electrical load connected to a multi-phase switchable DC/AC frequency convertor comprising a plurality of controllable switches. The value is realized by varying a current or a voltage delivered by the DC/AC frequency convertor through suitable switching of the switches thereof, and wherein the quantity exhibits a load angle which, averaged in time, leads or lags the voltage or current being delivered.

Abstract: A motor control device that can reduce electrical noise is provided. A motor control device includes an inverter, a current controller, a high frequency wave superpositioner, and a high frequency wave setter. An inverter applies a current to the motor. A current controller outputs a voltage to the inverter according to a current applied to the motor from the inverter. A high frequency wave superpositioner applies a high frequency wave to the voltage from the current controller as a superpositioned wave to infer a position of a rotor in the motor. A high frequency wave setter varies at least one characteristic of the superpositioned wave applied by the high frequency wave superpositioner.

Abstract: A full-closed control apparatus for performing velocity control based on a velocity signal of a motor and performing position control based on a position signal of a load driven by the motor, including: an equivalent rigid system velocity loop model; a band-pass filter; an amplitude adjuster; and a unit for inputting a velocity instruction of a velocity control loop into the equivalent rigid system velocity loop model, inputting a difference signal obtained by subtracting an output of the equivalent rigid system velocity loop model from a velocity signal of the load into the band-pass filter, inputting an output of the band-pass filter into the amplitude adjuster and outputting a signal obtained by adding an output of the amplitude adjuster to an output of a position controller, as a new velocity instruction.

Abstract: A method and apparatus for use with a controller that samples a command frequency and provides modulating waveforms to a PWM inverter as a function of the sampled command frequency, the inverter also receiving a carrier signal having a carrier frequency, the method for reducing distortions in the modulating waveforms that result from sampling characteristics of the controller, the method comprising the steps of sampling the command frequency at a sampling frequency to generate a series of sampled signals, integrating the sampled signals to generate a phase angle, identifying a correction angle as a function of the sampling frequency, adding the correction angle to the phase angle to generate a corrected phase angle and using the corrected phase angle to generate the modulating waveforms to be provided to the PWM inverter

Abstract: A space vector pulse-width modulator (SVPWM) and a method implemented by the modulator. A precalculation module accepts Ua and Ub modulation indexes and in response thereto, outputs modified Ua and Ub information; a sector finder has a U module which receives the modified Ua information and outputs a U sector; and a Z module which receives the U sector and the modified Ub information and outputs a Z sector. The U sector and the Z sector are 2-phase control signals for implementing 2-phase modulation. For 3-phase modulation, the SVPWM and method further possess an active vectors calculation module and an assign vectors module which receive the modified Ua and Ub information and the U sector, and which calculate active vectors for 3-phase modulation; a zero vector selector which receives the Z sector and calculates zero vectors for 3-phase modulation; and a PWM counter block which receives the active vectors and zero vectors and outputs 3-phase control signals for implementing 3-phase modulation.

Abstract: A method of regulating the power demanded by a rail motor including a current collector system cooperating with a catenary supplied with direct current power by power supply substations distributed along the track includes the steps of: measuring the catenary voltage Vcat at the rail motor, measuring the catenary current Icat at the rail motor, evaluating the no-load voltage Vcat0 of the substation supplying power to the catenary to which the rail motor is connected, evaluating the maximum power available to the catenary from the equation: P ⁢   ⁢ max = ( Vcat 0 ) 2 4 * R where R is the resistance of the catenary, and limiting the power demanded by the rail motor to a power limit Plim less than or equal to the calculated maximum power Pmax.

Abstract: A method for dynamically controlling regenerating energy flow and direct current bus voltage for an adjustable frequency drive system includes sensing a direct current voltage of a direct current bus; and sensing a plurality of alternating currents at outputs of an inverter. The sensed alternating currents are transformed to a stationary current vector. Voltage and frequency values are converted to a stationary voltage vector and an angle. The angle and the stationary current vector are transformed to a rotating current vector including torque and flux producing current components. An induction machine generating mode is determined when the torque producing current component reverses polarity. The voltage and frequency values limit the direct current voltage of the direct current bus at a predetermined threshold responsive to the generating mode. The stationary voltage vector and the angle are converted to pulse width modulated control inputs of the inverter.

Abstract: A controller for a multiplex winding motor. When a multiplex winding motor is driven and controlled by inverters and each winding includes a current control system, the controller compensates interference between the current control systems of windings. Voltage non-interacting arithmetic sections compute a voltage command value supplied to voltage applying sections, which are connected to a set of windings, not only by using an output value of a current control section for controlling current in one winding but also using an output value of a current control section for controlling current in another winding, so that voltage interference between the current control sections is compensated.

Abstract: A motor drive device of the invention has means for producing a pulse signal having a fixed amplitude by comparing a drive signal that is a sinusoidal signal synchronous with the rotation of a motor with a predetermined high-frequency signal, and the switching of a switching device connected between a power source and the motor is controlled by the pulse signal. This prevents the lowering of the switching speed of the switching device connected between the power source and the motor near the zero-cross points of the sinusoidal drive signal. This helps minimize switching loss and enhance power efficiency. Moreover, the phase current that flows through the motor comes to have a sinusoidal waveform. This helps enhance rotation characteristics.

Abstract: DC motor rotation speed alarm circuitry includes an input node, a connection node, a ground node, a comparison circuit and a signal generator. When the rotation speed of the DC motor changes during operation, floating voltage is generated between the driving circuit and the ground node. If the floating voltage is less than a preset voltage of the comparison circuit, the alarm signal outputted by the signal generator indicates that the DC motor is operating normally. If the floating voltage is greater than the preset voltage of the comparison circuit, the alarm signal outputted by the signal generator indicates that the DC motor is operating abnormally.

Abstract: System and method for enhancing the torque output of a field oriented induction motor including a controller having a plurality of predetermined control parameters operable for processing input signals to generate output signals. The plurality of predetermined control parameters are dependent upon the nature of the input signals and the operational state of the motor. A sensor system is operable for communicating feedback signals related to the output signals and the operational state of the motor from the motor to the controller.

Abstract: A method to estimate motor speed for extended stabilized rotational control of an induction motor at all speeds including slow speeds. The speed estimator supplies real-time time motor control feedback information for a variable speed motor drive controller without a mechanical encoder. The speed estimator is based on an optimized fast orthogonal search algorithm with control of the carrier drive frequency to reduce computation time. The reduced processing time provides for an update rate to the motor controller sufficient to maintain motor stability to near zero the motor rated base speed.