摘要:
A synchronous motor driving apparatus having a power converter which applies AC variable voltages having variable frequency to a synchronous motor includes a pulsating current application unit for applying pulsating current to the synchronous motor and a magnetic pole position presumption unit. The magnetic pole position presumption unit detects two current values ΔIdcp1 and ΔIdcp2 on the positive side and two current values ΔIdcn1 and ΔIdcn2 on the negative side of the pulsating current and presumes the magnetic pole position of the synchronous motor on the basis of difference between change rates of ΔIdcp1→ΔIdcp2 and ΔIdcp1→ΔIdcp2.
摘要:
A motor drive system without any portion for directly detecting the rotor position, rotation speed and motor phase currents, capable of realizing a high-performance variable speed drive even at high carrier frequencies. When detecting a current from a DC power supply of an inverter for driving a motor, applied voltages and frequencies to the motor are controlled based on sampled values by sampling a current flowing as intermittent pulses in the vicinity of each power conduction time period.
摘要:
A synchronous motor driving apparatus having a power converter which applies AC variable voltages having variable frequency to a synchronous motor includes a pulsating current application unit for applying pulsating current to the synchronous motor and a magnetic pole position presumption unit. The magnetic pole position presumption unit detects two current values ΔIdcp1 and ΔIdcp2 on the positive side and two current values ΔIdcn1 and ΔIdcn2 on the negative side of the pulsating current and presumes the magnetic pole position of the synchronous motor on the basis of difference between change rates of ΔIdcp1→ΔIdcp2 and ΔIdcp1→ΔIdcp2.
摘要:
An AC motor control apparatus that is applicable to commonly used PM motors and capable of detecting the magnetic pole position with simple algorithm. The AC motor control apparatus comprises an inverter for applying arbitrary AC power to an AC motor and a controller for sending a control signal to the inverter. The controller comprises a ripple current generator for supplying a ripple current to the AC motor and a magnetic pole position estimator. The magnetic pole position estimator observes at least two current values of the ripple current for both positive and negative sides of the ripple current to estimate the magnetic pole position of the AC motor.
摘要:
A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit. Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.
摘要:
In order to provide a driving device for a motor having a capability equivalent to conventional vector control type sensorless method by simplifying the controls structure to reduce number of parts to be adjusted, and to stabilize the control system, a driving device for a synchronous motor does not include a speed controller or a current controller, and calculates a voltage impressed on a motor on coordinate axes (dc/qc axes) based on a magnetic pole axis. For calculating a voltage command, command values such as a rotation speed command and a current command are used, and Iq* corresponding to a torque current command is calculated and provided based on a detected current value.
摘要:
A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit.Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.
摘要:
A synchronous motor drive system in accordance with the present invention detects a DC current of an inverter which drives a synchronous motor, and based on the magnitude of the current, estimates torque current components that flow through the motor, and then based on the estimated value, determines the voltage which is applied to the motor, and finally estimates and computes the magnetic pole axis located inside the motor using the estimated value of the torque current.
摘要:
Axial error calculation unit is provided for estimating an axial error &Dgr;&thgr; between a d-q axis and a dc-qc axis by using Ld, Lq, Ke, Id*, Iq*, Idc and Iqc in a range of all rotational speeds except zero of a rotational speed command of a synchronous motor, Ld denoting an inductance on a magnetic pole axis d of the synchronous motor, Lq an inductance on a q axis orthogonal to the magnetic pole axis d, Ke a generated power constant of the motor, Id* a current command of the d axis, Iq* a current command on a q axis, Idc a detected current value on an assumed dc axis on control, and Iqc a detected current value on an assumed qc axis orthogonal to the assumed dc axis. Irrespective of presence of saliency, position sensorless control can be achieved in a wide range a low to high speed zone.
摘要:
Axial error calculation unit is provided for estimating an axial error &Dgr;&thgr; between a d-q axis and a dc-qc axis by using Ld, Lq, Ke, Id*, Iq*, Idc and Iqc in a range of all rotational speeds except zero of a rotational speed command of a synchronous motor, Ld denoting an inductance on a magnetic pole axis d of the synchronous motor, Lq an inductance on a q axis orthogonal to the magnetic pole axis d, Ke a generated power constant of the motor, Id* a current command of the d axis, Iq* a current command on a q axis, Idc a detected current value on an assumed dc axis on control, and Iqc a detected current value on an assumed qc axis orthogonal to the assumed dc axis. Irrespective of presence of saliency, position sensorless control can be achieved in a wide range a low to high speed zone.