Abstract: A resolver includes a first coil group and a second coil group. The first coil group has a first exciting coil and a first detecting coil that have a multiplication factor of angle of nX (where n is a natural number equal to or greater than three), are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. The second coil group has a second exciting coil and a second detecting coil that have a multiplication factor of angle of (n?1)×, are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. Furthermore, the first coil group and the second coil group are provided at positions different in a radial direction from each other.

Abstract: This application relates to a motor controller applied to an electric vehicle, a microprocessor in the motor controller, and a sampling trigger method applied to the microprocessor. The sampling trigger method includes: a signal generation module generates an exciting fundamental wave signal to drive the resolver to work; a signal processing module determines an exciting symbol based on the exciting fundamental wave signal, where the exciting symbol includes alternate high-level signals and low-level signals, and the signal processing module further determines a zero crossing point signal of the exciting fundamental wave signal based on the exciting symbol; and a phase shift processing module performs phase shift processing on the zero crossing point signal to obtain a sampling trigger signal, to trigger the microprocessor to sample the resolver feedback signal. In this solution, fewer peripheral circuits of a chip are used, thereby improving a product integration degree.

Abstract: A motor control device is a device for controlling a drive of a DC motor which is interlocked with an output shaft portion of an actuator. The motor control device includes: a relative position obtainer detecting current fluctuations when switching a connection between a commutator and a brush in the DC motor or when rotating the DC motor and obtaining relative position information of the output shaft portion; and an absolute position obtainer obtaining absolute position information of the output shaft portion using a potentiometer. The motor control device further includes: an actual position setter setting actual position information of the output shaft portion based on at least one of the absolute position information and the relative position information.

Abstract: A machine controller for controlling a machine detects an absolute position of a detection target using a detector outputting rotation number data corresponding to a position of the detection target, and controls the machine based on the detected absolute position of the detection target. The machine controller includes: a storage unit which stores rotation number data, of the detector, that corresponds to a zero point position of the absolute position, as zero point position data, and which stores rotation number data exceeding a rotation number data length that the detector can output, as extended rotation number data; and a calculation unit which calculates the absolute position in accordance with Formula (1) below that is based on the rotation number data output from the detector, the zero point position data, and the extended rotation number data: Absolute position=(Rotation number data from the detector+Extended rotation number data)?Zero point position data?? (1).

Abstract: It is an object of the present invention to provide an encoder that is easier to use. An encoder 1 used in a numerical control device includes a signal generation unit configured to generate a digital signal, and a configuration information output unit configured to output configuration information that determines operation of the signal generation unit, in which the configuration information output unit includes a voltage level acquisition unit that acquires a voltage level to be input, a configuration information selection unit that selects configuration information according to the acquired voltage level among a plurality of types of configuration information, and a configuration information transmission unit that transmits the selected configuration information to the signal generation unit.

Abstract: An apparatus for generating a resolver excitation signal and a vehicle including the same are provided. The apparatus includes an input portion that is configured to receive an input signal and a current amplifier that is configured to generate an output signal by amplifying the input signal and that has a circuit protector that protects a circuit from an overcurrent. An output portion is configured to output the output signal. Additionally, the circuit protector includes a first transistor that has an emitter connected to the output portion, a second transistor that has a collector connected to the output portion and a base connected to a base of the first transistor and a rectifier connected to a base of the first transistor and the base of the second transistor.

Abstract: Provided is a brushless DC motor (2) including: a stator (5) around which windings are around; a magnet rotor (6) configured to rotate by a power supply to the stator; an inverter circuit (11) connected to the stator; a position detector (7) configured to detect a positional relationship between the magnet rotor and the windings; a speed instruction unit (13) configured to output, as a speed instruction signal, a voltage corresponding to a rotation speed of the magnet rotor; a duty determination unit (12) configured to determine a duty of a voltage applied to the stator, based on the speed instruction signal; a drive controller (14) configured to distribute and output a duty signal based on the positional relationship and the duty; and temperature-sensitive resistance elements (15) configured to, by increasing the resistance in response to a temperature rise, reduce the voltage given as the speed instruction signal.

Abstract: A rotation detecting device is configured to be used with a switch and detect rotation of a rotation shaft having a magnetic body attached thereto. The rotation detecting device includes a magneto-resistive element facing the magnetic body and outputting a first signal related to displacement of the magnetic body, a Hall element facing the magnetic body and outputting a second signal related to displacement of the magnetic body, and a detection circuit having the first and second signals input thereto. The detection circuit is configured to: output the first signal while the switch is turned on; detect rotation-number information corresponding to the number of rotations of the rotation shaft based on the second signal at a first time point at which the switch is turned off; store the rotation-number information; and output the stored rotation-number information at a second time point when the switch is turned on after the first time point.

Abstract: A servo transmission mechanism includes a servo main body, a first housing, a second housing, a connecting rod, and a linking member. The semi main body includes a first end having an output shaft and a second opposite end. The first housing is connected to the output shaft of the servo main body. The connecting rod has an upper end and a lower end that includes a connecting shaft, opposite ends of which are rotatably connected to the first housing and the second housing, respectively. The linking member rotatably connects the upper end of the connecting rod to the second end of the servo main body.

Abstract: A method for monitoring that includes the steps of: associating a monitoring module with a heat exchanger unit; operating the monitoring module whereby a microcontroller performs various tasks, and ultimately providing an indication; and taking an action based on the indication. The monitoring module includes an at least one sensor proximate to the cooling side. The module also includes a logic circuit having a microcontroller in operable communication with the at least one sensor.

Abstract: A method for detecting an open resolver exciter line (10) comprises the following steps: —measuring the signal voltages Us and Uc of the sine coil (17) and the cosine coil (18) of the resolver (15); —comparing the amplitude Us2+Uc2 of the resolver signal to a first threshold value CS1; —starting a diagnostic mode having the following steps if the amplitude Us2+Uc2 does not reach the first threshold value CS1; —applying a constant voltage to the exciter line (11, 12) via a series resistance (25) RLE that is large compared to the ohmic resistance of the exciter coil (16) RE; —measuring the voltage difference UE(t1) at the terminals (5, 6) of the exciter line at a number of points in time ti during at least one excitation period; and —determining the DC voltage component UE,Offs of the voltage difference UE; —determining that there is an open exciter line (10) if, during the excitation period, the DC voltage component UE,Offs is larger than a second threshold value CS2.

Abstract: Systems and methods for controlling a DC to AC inverter providing a multiphase output at a fundamental frequency are provided. More particularly, a synchronous reference frame control scheme can be employed to regulate a DC to AC inverter to attenuate error at various frequencies of interest for the DC to AC inverter. According to particular example aspects of the present disclosure, the synchronous reference frame control scheme can include control structures to provide for attenuation of the negative sequence and zero sequence currents, leading to reduced total harmonic distortion and voltage unbalance in the output voltage of the inverter.

Abstract: In one embodiment, a sensor circuit may include a first receiver circuit that may be configured to receive a first signal that is representative of a first mutual inductance and form a first detection signal that is representative of the first mutual inductance, wherein the first variable mutual inductance varies in response to a position of a metal object. An embodiment may include a second receiver circuit configured to receive a second signal that is representative of a second mutual inductance and form a second detection signal that is representative of the second mutual inductance, wherein the second mutual inductance varies in response to the position of the metal object. In an embodiment, the sensor circuit may include a recognition circuit configured to assert a movement detected signal responsively to a first value of the first detection signal, configured to assert a movement direction signal responsively to a first value of the second detection signal.

Abstract: A sinusoidal-amplitude-to-digital-output circuit includes a comparator with an input terminal, a reference terminal and an output terminal. A digital bus is connected to the output terminal. A reference voltage source is connected to the reference terminal. A feedback resistor is connected in parallel with the comparator between the output terminal and the input terminal to provide hysteresis for noise rejection such that circuit converts voltage received at the input terminal into a digital pulse-width modulated waveform that varies non-linearly with amplitude of the voltage received at the input terminal.

Abstract: A resolver has a lead wire that can be slack even in a structure in which it is impossible to maintain the distance between an end of wound wire and a terminal pin without using a special jig. A lead wire of a stator coil 500 is entwined on a plurality of terminal pins 603 in a slack condition, and the entwined parts are fixed by soldering or welding. Terminal base 600 is then moved to a stator core 200 side, and the lead wire is made slack by contacting the lower surface of a terminal base body 601 to the upper surface of the stator core 200. Next, end part of the pins 306 of a primary insulator 300 are melted so as to fix the terminal base 600.

Abstract: A sensor device analogical output signal shifting system including the sensor device including at least two detection cells adapted to equip a mechanical device and deliver at least two analogical output signals depending on behavior of the mechanical device. A shifter circuit selectively processes the analogical output signals and including at least a first part including at least one passive analogical component having a variable parameter and a second part including at least one passive analogical component having a variable parameter; and a control component for controlling the variable parameters of the passive analogical components, a variation of these variable parameters shifting at least one of the sensor device analogical output signals in the circuit. The circuit delivers at least two sensor device analogical output signals, including at least one shifted output signal including the first shifted analogical output signal and/or the second shifted sinusoidal signal of the sensor device.

Abstract: The invention relates to an inductive angle sensor that includes a measuring element able to be positioned, within an angle measurement range, in different angle-positions about a rotational axis, as well as a coil that is at a distance from said measuring element. The surface of the measuring element is at a different distance from the coil in each angle-position, within said angle measurement range.

Abstract: A motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.

Abstract: An industrial robot with a manipulator arm including at least one manipulator element and an electric motor driving the at least one manipulator element. An energy reservoir supplies the electric motor with electricity when a power failure or power loss occurs to move the manipulator element from a working position to a safe parking position. Also a method of parking a manipulator arm of an industrial robot.

Abstract: Phase information of a rotation system is obtained by a) reading the present output value Sk, (k=0, . . . , N?1) of the sensor at a sequence of N points of time during a first period of a periodic modulation function (PHA,PHB,PHC, PHD), b) storing read output values Sk or a value derived from this output value at least temporarily in a memory, c) extracting information on the phase of the rotating system, wherein said information is extracted based on evaluation of a function of the type, wherein=and, and d) sampling and storing sequentially further output values Sk, k=N,N+1, . . . of the sensor at corresponding points of time in the following periods of the periodic modulation function (PHA,PHB,PHC, PHD). Each reading information on the phase of the rotating system based on the function is extracted and a controller device (100) for application of this technique.

Abstract: A method of correcting a sensor that detects a detection object and generates a detection signal includes: determining a homing-signal generation time difference between points of time when the detection signal is generated according to a direction in which the detection object enters the sensor and correcting a homing-signal generation time by using the determined homing-signal generation time difference.

Abstract: Two excitation coils (excitation A coil, excitation B coil) and two detection coils (detection A coil, detection B coil) are provided. The excitation A coil and the excitation B coil are excited at frequencies that are different from each other. The number of turns of the detection A coil and the detection B coil are respectively set with two sine waves using the number ms1 and ms2 of pole pairs. The number ms1 and ms2 of pole pairs, the number mx1 and mx2 of pole pairs of the excitation A coil and the excitation B coil, and the number mr of pole pairs of a rotor are set to have a predetermined relationship. A resolver having redundancy can be realized with small number of coils.

Abstract: Provided is a system and method for calibrating an offset of a resolver in a motor of a vehicle. More specifically, a current is applied to the ?d-axis of the motor, the Vq, Vd, Iq, and Id of the motor is measured and a power input to the motor is calculated by a controller, and when the input power is not within a predetermined range, the controller adjusts the offset of the resolver to a positive or negative value accordingly.

Abstract: An apparatus for measuring an error in a resolver includes a first calculator that perform an inverse Park transform based on voltages Uq and Ud at an output of PI current regulators, and delivers voltage setpoint signals PWMA, PWMB, PWMC to a power stage via a line on which a DC voltage Ubus-dc is available. The power stage generates a three-phase system of voltages UA, UB, UC for energizing an electric machine. The apparatus also includes a signal processor that provides an angle measurement ?m. Based on currents MesIA, MesIB, MesIC of the three phases, and on a rotor angle ?r, a second calculator of the device delivers values MesId, MesIq used by the first calculator. A PI voltage regulator delivers an angle ?c for correcting the error by regulating a setpoint value for the voltage Ud.

Abstract: The present invention relates to a reluctance resolver (100) with an at least partially soft magnetic stator (104) and an at least partially soft magnetic rotor (102) which oppose each other by forming an air gap. The magnetic resistance in the air gap changes periodically on account of a configuration of the rotor that varies over the circumference. The angle sensor has a magnetic flux transmitter which is arranged on the stator and generates a predefined magnetic flux distribution in the air gap via at least one pair of poles. Furthermore, a magnetic flux receiver, which measures the intensity of the magnetic field via at least two pairs of signal poles arranged offset from one another at an angle, is arranged on the stator, wherein an angle value for a position of the rotor in relation to the stator can be derived from the two receiver signals.

Abstract: A resolver signal converter and a resolver signal conversion method amplify and perform analogue-digital conversion on a sine wave output from a resolver; thereafter, among frequency components of the sine wave output, pass and thereby extract a predetermined bandwidth of which the center frequency is the frequency of an excitation signal, by means of a band-pass filter; sample the sine wave output while synchronizing the sine wave output with a reference signal which is based on the excitation signal; and generate a detection angle signal sine value from the sampled signal. Similarly, a detection angle signal cosine value is generated from a cosine wave output from the resolver. A detection angle is calculated based on the detection angle signal sine value and the detection angle signal cosine value.

Abstract: The present invention is directed to a method of estimating a motor rotation angle that does not affect precision of a detected angle of a crank angle sensor, which is an alternative sensor, when abnormality occurs in a resolver and a peripheral circuit, and performing a motor control without failure of an inverter or peripheral device. A vehicle system includes a motor, a resolver detecting a rotor rotation angle of the motor, a motor control circuit controlling the motor based on information on rotor rotation angle and torque command value, an engine connected to the motor through a crankshaft, and a crankshaft sensor detecting revolutions of the crankshaft, in which the motor control circuit estimates rotor rotation angle based on a variation rate of the number of revolutions of the crankshaft when abnormality of the resolver is detected, and performs a weak field control based on estimated rotor rotation angle.

Abstract: A sensor system for providing control of an electric motor having an inductive angle sensor system including a first inductive coil configured for affixation to a rotor shaft of the electric motor wherein rotation of the rotor shaft causes corresponding rotation of the first inductive coil. A second inductive coil fixedly mounted in spaced relationship to the first inductive coil. An evaluation circuit coupled to the second inductive coil and to the electric motor operative to determine a rotor shaft angle for the rotor shaft of the electric motor through evaluation of an induced magnetic field between the first and second inductive coils.

Abstract: A motor control device determines a rotation angle and an angular speed of a motor, and has: a correcting unit including N number (N is an positive integer equal to or more than 2) of bit-shift circuits, which divide the angular speed by powers of 2 by bit shift, and a circuit, which subtracts output values of the second to Nth bit-shift circuits from an output value of the first bit-shift circuit to determine a correction amount for the rotation angle and correct the rotation angle by the correction amount; so as to determine two-phase direct voltages to obtain a target torque from the three-phase alternate currents passing through the motor according to the angular speed, and convert the two-phase direct voltages into the three-phase alternate voltages according to the sine, cosine of the corrected rotation angle.

Abstract: A control device divides 360° corresponding to one cycle of a resolver angle into N zones, and determines whether or not a resolver angle ? in the current cycle exceeds a division border. When determined that resolver angle ? in the current cycle exceeds a division border, the control device calculates a time difference ?T[n] between a calculation time T[n] in the immediately preceding resolver cycle and a calculation time T in the current cycle. The control device also calculates a resolver angle variation ??[n] with time difference ?T[n] by adding 360° to the difference between resolver angle ? obtained in the current cycle and a resolver angle ?[n] obtained in the immediately preceding resolver cycle. The control device then calculates a rotation speed NM by multiplying, by a coefficient K, a value obtained by dividing ??[n] by ?T[n].

Abstract: A motor speed determining circuit determining a rotation speed of a motor is provided and a processing of generating motor driving waveform is switched in accordance with the rotation speed of the motor. A resolver signal outputted from a resolver 2 is converted to a digital value by an R/D converter 3, and inputted to a computing circuit of resolver value correction 5 via an R/D conversion interface 4. A current value of a motor M is converted to a digital value by an A/D convertor 8. The computing circuit of resolver value correction 5 computes a resolver correction value of the inputted digital signal and calculates positional data from a corrected resolver value. The computing circuit of motor control computes a current instruction value from a motor current value subjected to digital conversion by the A/D converter 8 and a motor current instruction value etc.

Abstract: A position control apparatus calculates a position detection value by adding an output of a first-order delay circuit 17 that receives a difference between a driven member position detection value Pl and a motor position detection value Pm to the motor position detection value Pm, and uses the obtained position detection value as a position feedback value. An aging corrector 30 suppresses low frequency vibrations by controlling a time constant Tp of the first-order delay circuit 17 in such a way as to increase the time constant when a vibratory state of the driven member is detected.

Abstract: A method and an arrangement for determining the rotation speed of a motor fed by an inverter, the arrangement comprising means for determining the rotation speed of the motor in at least two alternative manners, whereby the means for determining the rotation speed of the motor comprise one of the at least two alternative manners of performance: means for measuring the frequency of the voltage fed to the motor by the inverter; and means for estimating the rotation speed of the motor on the basis of the measured frequency.

Abstract: An encoder includes: a main scale having two or more band-shaped tracks in each of which an optical main grating is formed so that longitudinal direction of the main scale corresponds to a measurement axis direction; and an index scale opposed to the main scale so as to form a diffraction interference optical system in cooperation with the main grating, disposed so as to be movable relative to the main scale in the measurement axis direction, and in which two or more optical index gratings are formed. A plurality of slits included in the main grating in at least one track are formed so as to be inclined at a predetermined inclination angle from a direction perpendicular to the measurement axis direction so that pitch of the slits in the track becomes equal to the pitch of the slits in the at least one other track.

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: A system for controlling the feed of a yarn to a textile machine or a metal wire to a coil winder. The yarn or wire unwinds from its spool and cooperates with a rotary member associated with its own rotation actuator before being directed to the machine. The yarn or wire has a characteristic value of tension and/or speed and/or quantity during this feed, and the actuator has a stator and a rotor acting on an exit drive shaft, which has its own piloting arrangement. The rotary member about which the yarn or wire winds is keyed onto the exit drive shaft. This control system measures the angular position of the drive shaft and compares an instantaneous parameter of that angular position to a prefixed characteristic value of the yarn or wire Command signals are then fed to the actuator's piloting arrangement to conform the instantaneous parameter with this prefixed value.

Abstract: An electronic control system for a motor uses a test cycle to select an optimum mode of operation from a plurality of available modes of operation. In some embodiments, the test cycle produces test data that is compared to information in a library of operating parameters relating to the available modes of operation. An algorithm uses the information in the library of operating parameters to choose an optimum mode of operation. In certain embodiments, the test cycle tries each of the available modes of operation, monitors operational parameters, and determines the best performing mode of operation.

Abstract: Methods and apparatus are provided for a limp home operational mode for an electric motor system. The method includes determining whether a resolver has failed. When the resolver has not failed, operation of the electric motor system uses resolver signals. When the resolver fails, operation of the electric motor system uses sensorless rotor position and rotor speed signals.

Abstract: A method of processing a resolver fault in a motor generator unit (MGU) includes receiving a position signal from a resolver describing a measured angular position of a rotor of the MGU, determining the presence of the resolver fault using the position signal, and calculating or extrapolating an estimated rotor position when the resolver fault is determined. A predetermined resolver fault state may be determined using a measured duration of the resolver fault, and the MGU may be controlled using the estimated rotor position for at least a portion of the duration of the resolver fault. A motor control circuit is operable for processing the resolver fault using the above method, and may automatically vary a torque output or a pulse-width modulation (PWM) of the MGU depending on the duration of the resolver fault.

Abstract: The rotation angle detection device detects the rotation angle of a rotary member by employing, at the least, either a sine wave signal or a cosine wave signal that is generated as the rotary member is rotated, and employs a change per unit time in the sine wave signal or cosine wave signal to determine whether an output abnormality has occurred in the rotation angle detection device. Further, this rotation angle device is employed to detect the motor angle of an electric power steering apparatus.

Abstract: A control device for a travel motor mounted to a vehicle has a resolver which works as a rotation-angle sensor. The control device has a RDC which calculates a rotation-angle output value ? based on rotation detection signals Sa, Sb transferred from the resolver. The control device supplies electric power to the travel motor based on the rotation angle output value ?. The RDC calculates “sin(???)” as an error deviation ? based on the signals Sa and Sb and the rotation-angle output value ?. The RDC calculates an angular acceleration by multiplying the error deviation ? with a gain (=Ka·Kb), and integrates the angular acceleration two times in order to obtain a next rotation-angle output value. A gain control part of the RDC decreases the gain when the judgment means judges that the travel motor rotates at a constant rotation speed.

Abstract: In a method and apparatus for calibrating a position sensor mounted on the shaft of a permanent magnet synchronous motor, to control the position of a rotor of the permanent magnet synchronous motor relative to a magnetic field produced by a stator of the permanent magnet synchronous motor, a DC test current is supplied to stator windings of the permanent magnet synchronous motor to generate a definite magnetic field. The motor speed caused by the DC test current is adjusted to zero by modifying the rotor position; and the position measured by the position sensor at zero motor speed relative to the magnetic field is used to calibrate the position sensor.

Abstract: A control system and method to determine position of a rotor relative to a stator for a synchronous multipole electrical machine is presented, including one for application on a fuel/electric hybrid powertrain for a vehicle. The machine includes a stator, a rotor, and a rotor position sensing mechanism. The control system controls the electrical machine, in conjunction with an electrical storage device and an inverter, using algorithms and calibrations which derive a rotor position based upon a sensorless position sensing technique, and determine an offset from a sensed rotor position. Electrical output from the inverter to the machine is controlled based the offset, which is stored non-volatile memory. A rotor position is derived based upon a sensorless position sensing technique during initial machine operation after startup of the machine, and includes operation in a torque-generative mode and in an electrical energy-generative mode.

Abstract: A method for improving a failure mode diagnostic of an electric power steering system by overcoming a motor electric lock condition due to position sensor signal corruption or other motor faults. If certain conditions are met, the method determines that the motor is in an electric lock condition, and then reduces a torque current command to the motor so that it is able to be rotated by a vehicle hand-wheel. Once the motor is able to be rotated, then the method determines whether certain conditions have been met to determine whether the position sensor is malfunctioning.

Abstract: Methods and systems for detecting an angular position of an electric motor are disclosed, including sending an electrical pulse through a stator coil of the electric motor, determining an approximate angular position of a rotor of the electric motor in response to detecting an timing of a returning electrical pulse from the stator coil, the timing of the returning electrical pulse being indicative of the angular position of the rotor; and determining an accurate position of the rotor in response to sensing a transition of a digital sensor in response to the rotor rotating relative to the stator, the transition being indicative of the accurate position.

Abstract: A fuel burner controller and associated method is configured to establish fuel combustion in a fuel burner and to recycle a fuel combustion initiation process when a loss of combustion is detected and a call for heat is asserted. The controller is further configured to limit a number of recycles of the fuel combustion initiation process based on a time budget.

Abstract: An apparatus, system, and method are provided for simulating outputs of a resolver. One apparatus includes an adjustable sine waveform generator for simulating first and second sine wave signals, and an adjustable cosine waveform generator for simulating first and cosine wave signals. The apparatus also includes an adjustable waveform generator and an adjustable gain circuit coupled to the sine waveform generator and cosine waveform generator. The system includes a device simulating a resolver coupled to a motor controller. The device includes an adjustable sine waveform generator and an adjustable cosine waveform generator coupled to an adjustable waveform generator and an adjustable gain circuit. One method includes transmitting a signal simulating at least one resolver fault condition to a motor controller to determine if the motor controller detects the fault condition(s).

Abstract: A motor controller includes a reference signal generator; an A/D converter performing A/D conversion of the cosine and the sine signals outputted from a resolver; a first amplitude calculator calculating cosine and sine signal amplitudes based on twice-A/D converted cosine and sine signals respectively; a second amplitude calculator calculating averages of the cosine and the sine signals, and that calculates the amplitude of the cosine signal from a difference between the cosine signal average and a latest A/D converted cosine signal, and that calculates the amplitude of the sine signal from a difference between the sine signal average and a latest A/D converted sine signal; a synthesizer synthesizing the cosine and sine signal amplitudes obtained by the first and the second amplitude calculators respectively; a rotational angle calculator calculating a rotational angle based on the synthesized cosine and sine signal amplitudes; and a PWM controller.

Abstract: Apparatus and methods are provided for diagnosing faults in multiple, associated motor-resolver systems. One apparatus includes a swapping circuit coupling a first resolver to a first or second decoder, and a swapping circuit coupling a second resolver to the first or second decoder. One method includes applying a signal from a resolver to a first decoder to determine that the first decoder is malfunctioning if the first decoder continues to generate a fault signal, and applying a signal from a different resolver to a second decoder to determine that a motor associated with the first decoder is malfunctioning if the second decoder generates a fault signal. Another method includes transmitting a signal from a resolver to first and second decoders, transmitting a signal from a different resolver to the first and second decoders, and determining if the first decoder, second decoder, a first motor, or a second motor is malfunctioning.

Abstract: A resolver includes an excitation signal generator which generates a sine wave and a cosine wave as an excitation signal, a rotor which receives the excitation signal, and a rotary transformer which detects an output signal of the rotor, the resolver being arranged to detect angle information of the rotor. The resolver further includes a controller which outputs angle information at a zero cross point of the output signal detected by the rotary transformer. The resolver can provide high detection accuracy and be low in cost.