Hitachi, Ltd.

Hitachi Power Semiconductor Device, Ltd.

Satoshi Sumita

Yoshitaka Iwaji

Daisuke Maeda

Kazuaki Tobari

Shigehisa Aoyagi

Yasuo Notohara

Disclosed are a motor control system and a motor control method that allow the balance of evaluation values in a trade-off relationship to be easily adjusted. The motor control system includes: an inverter () that applies AC voltage to a motor (); a control unit () that generates a voltage command for AC voltage in response to a control command; and a feedback unit () that applies a correction value to the control unit. The feedback unit estimates a plurality of evaluation values from a state quantity using a plurality of regression formulas, where at least one state quantity (x1, x2) of the motor is an input variable and a plurality of evaluation values (y1, y2) of the motor or a motor-driven object () are output variables, calculates an evaluation function with the estimated plurality of evaluation values as arguments, and generates a correction command on the basis of a calculation value resulting from the evaluation function.

Motor control system and motor control method

Provided is a control device of an AC motor, including: an inverter including a switching element; switching control means for controlling the switching element; and phase detection means for detecting a rotor phase of an AC motor, wherein the switching control means controls the switching element so that a voltage waveform of the inverter has half-wave symmetry in an interval of a width centering on a fundamental voltage phase of 180 deg&#xb1;180 deg, the switching control means controls the switching element so that a harmonic voltage phase of the inverter becomes variable on the basis of a fundamental voltage-rotor phase difference which is a difference between a fundamental voltage phase and the rotor phase of the AC motor, and the switching control means controls the switching element so that a harmonic voltage amplitude of each order of the inverter is inversely proportional to the order.

Control device of AC motor

The invention is directed to omit an adjustment work of a motor control system and increase versatility. Provided is a motor control system including: an inverter which outputs a voltage to a motor based on a voltage command; a current detecting unit which outputs a current detection value based on a current flowing through the motor of a state quantity detecting unit; a voltage command calculating unit which outputs the voltage command of the state quantity detecting unit based on the high-order command and the current detection value of the state quantity detecting unit; a storage unit which outputs a data set of the quantity of state of the state quantity detecting unit based on the quantity of state of a driving target of the motor of the state quantity detecting unit; an abnormality degree calculation equation updating unit which outputs an abnormality degree calculation equation for computing the abnormality degree of the driving target of the state quantity detecting unit based on the data set of the state quantity detecting unit; an abnormality degree calculating unit which outputs the abnormality degree based on the quantity of state of the state quantity detecting unit and the abnormality degree calculation equation of the state quantity detecting unit; and a voltage adjusting unit which outputs an adjustment voltage for adjusting the voltage command of the state quantity detecting unit based on the abnormality degree of the state quantity detecting unit.

Motor control system

A control apparatus and a control method for an AC electric motor detect DC bus current plural times at predetermined intervals during first and second predetermined periods and multiply vectors having integrated values of detected values during respective periods as elements by an inverse matrix of a matrix having integrated values during respective periods of sine and cosine functions of output voltage phase of an inverter at the moment that detection is made as elements to thereby estimate reactive and active currents.

Control apparatus and control method for AC electric motor

If magnitude relations between the output terminal voltage based on a DC negative terminal of the inverter and a threshold voltage that is a fixed value are compared, polarity thereof is changed at a predetermined rotor phase. The magnitude relation, for example, is detected by an inexpensive and simple apparatus such as a level shift circuit and a NOT circuit. The rotor phase of the permanent magnet synchronous motor is inferred on the basis of changes in the magnitude relation and if it is differentiated, a rotation speed is inferred. If the inferred values of the rotor phase and rotation speed are fed back to synchronous operation or vector control, the free-running permanent magnet synchronous motor is restarted.

Growing community of inventors

Tokyo, Japan

Satoshi Sumita