摘要:
It is an object of the invention to provide a control device for a synchronous motor which can detect the position of a magnetic pole from a zero speed without requiring a signal generator. The invention provides a control device for a synchronous motor which drives the synchronous motor through a voltage-operated PWM inverter and controls a torque and a speed of the motor, including means (6-3) for causing a PWM carrier signal to have an arbitrary phase difference between two phases such as UW, VW or WU in three phases of U, V and W, means (11) for extracting a high frequency voltage and a high frequency current which are thus generated from a detecting voltage or a command voltage and a detecting current, and means (12) for estimating a position of a magnetic flux or a position of a magnetic pole by using the high frequency voltage and the high frequency current which are extracted.
摘要:
A control device is provided for a synchronous motor, which drives the synchronous motor through a voltage operated PWM inverter and controls a torque and a speed of the motor, including a unit for causing a PWM carrier signal to have an arbitrary phase difference between two phases such UV, VW, or WU in three phases of U, V, and W, a unit for extracting a high frequency voltage and a high frequency current, which are thus generated from a detecting voltage or a command voltage and a detecting current, and a unit for estimating a position of a magnetic flux or position of a magnetic pole by using the high frequency voltage and the high frequency current which are excited.
摘要:
It is an object of the invention to provide an apparatus for estimating a magnetic pole position of a motor in which the amplitudes of high-frequency currents can be adjusted. In the invention, a controlling apparatus for driving a motor (1-1) by a voltage source PWM inverter (1-2), and controlling a torque and speed, or torque, speed, and position of the motor has: means for switching over first means for producing an arbitrary phase difference in PWM carrier signals between respective two phases such as UV, VW, or WU of three or UVW phases, and second means for causing the phase difference between two phases such as V, VW, or WU of three or UVW phases to become zero; means for extracting high-frequency currents in a same frequency band as carrier signals generated by it, from estimated currents; and means (1-4) for estimating a magnetic pole position by using the extracted high-frequency currents.
摘要:
It is an object of the invention to provide an apparatus for estimating a magnetic pole position of a motor in which the amplitudes of high-frequency currents can be adjusted.In the invention, a controlling apparatus for driving a motor (1-1) by a voltage source PWM inverter (1-2), and controlling a torque and speed, or torque, speed, and position of the motor has: means for switching over first means for producing an arbitrary phase difference in PWM carrier signals between respective two phases such as UV, VW, or WU of three or UVW phases, and second means for causing the phase difference between two phases such as V, VW, or WU of three or UVW phases to become zero; means for extracting high-frequency currents in a same frequency band as carrier signals generated by it, from estimated currents; and means (1-4) for estimating a magnetic pole position by using the extracted high-frequency currents.
摘要:
A motor control device includes a current profile generator generating a current profile, a pilot voltage operator calculating a pilot pulse voltage, on the basis of the current profile, and adding the pilot pulse voltage to a voltage command on a d axis, a magnetic pole position detector detecting a position of a magnetic pole in the permanent magnet motor, on the basis of the pilot pulse voltage, a polarity identification evaluation current operator calculating a polarity identification evaluation current for identifying a polarity of the magnetic pole in the permanent magnet motor, on the basis of a current value on the d axis in the motor current that has been detected in synchronization with a period of PWM control, and a polarity detector outputting a phase correction amount, on the basis of a deviation between the polarity identification evaluation current and the current profile.
摘要:
The invention has an object to provide a magnetic pole position estimating method and a control apparatus for a synchronous motor which reliably detect the position of a magnetic pole of the synchronous motor to carry out stable control also when a high load is applied or a load is suddenly changed. A coordinate transformer (8) transforms a detected current value is into an impedance observation axis positioned in a place shifted from an estimated magnetic pole position &thgr;{circumflex over ( )} by 45 degrees. A high-frequency impedance estimator (10) estimates high-frequency impedances Zdm and Zqm on two points which are advanced and delayed by an electrical angle of 45 degrees from a &ggr;-axis. A first magnetic pole position estimator (13) estimates a first magnetic pole position estimated value &thgr;{circumflex over ( )} to eliminate a deviation between the high-frequency impedances Zdm and Zqm. A second magnetic pole position estimator (14) inputs a current command value i&dgr;* to estimate an internal phase angle compensating angle &thgr;{circumflex over ( )}r and subtracts the internal phase angle compensating angle &thgr;{circumflex over ( )}r from the first magnetic pole position estimated value &thgr;{circumflex over ( )}, and outputs a second magnetic pole position &thgr;{circumflex over ( )}c.
摘要:
A control device for an alternating current motor according to embodiments includes a current distributor and a phase estimator. The current distributor divides a torque command by using a control phase and outputs a component that contributes to a mechanical output of the motor as a δ-axis current command and a component that does not contribute to the mechanical output as a γ-axis current command. The phase estimator computes a phase at which a γ-axis component of an addition amount of the output of the current controller and a voltage drop amount of inductance of the motor becomes zero and outputs the computed phase as the control phase.
摘要:
A three-phase-to-two-phase converter detects two-phase currents of three-phase stator currents, converts the stator currents into a &ggr;-&dgr; coordinate system to derive a &ggr;-axis current and a &dgr;-axis current. The &ggr;-axis current, the &dgr;-axis current, and voltage command values outputted respectively from a &ggr;-axis current controller and a &dgr;-axis current controller are entered to a stator current and induced electromotive force estimator, which determines estimated values of the stator currents and estimated values of an induced electromotive force in the &ggr;-&dgr; coordinate system.
摘要:
An alternating-current motor control apparatus includes a voltage controller configured to output a command voltage vector so that the command voltage vector is time-averaged for time periods, a square-wave voltage generator configured to control, every time period, amplitudes and phases of voltages to be applied to an alternating-current motor, a current detector configured to detect motor currents at a timing synchronized with periods 1/N-th of the time periods, where N is equal to or larger than one, a coordinate transformation section configured to perform coordinate transformation to transform the motor currents into two-phase currents, an envelope extractor configured to extract two-phase currents as waveforms having amplitudes that periodically change from the two-phase currents, and extract envelopes of the waveforms, and a magnetic-pole-position computing section configured to compute a magnetic-pole position using the envelopes.
摘要:
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.