Motor control apparatus, motor control method, control system, and position estimation method to be used in control system

Patent metadata

Field	Value
Publication number	US-10095244-B2
Application number	US-201514965364-A
Country	US
Kind code	B2
Filing date	Dec 10, 2015
Priority date	Aug 8, 2010
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

A motor control device may include a position command output means, a first subtraction means that calculates and outputs a position deviation, a position control means, a second subtraction means that calculates and outputs a position deviation, a speed control means that outputs a torque command, a limiter limits the level of the torque command, a motor drive means, and a voltage fluctuation detection means. When the voltage fluctuation detection means detects that the voltage of said power source has dropped below a predetermined reference level, either the position command output means varies the position command so as to reduce the rotational speed of the motor and/or said position control means limits said speed command to be output.

First claim

What is claimed:

1. A control system for use with a body to be controlled, the control system comprising:
a motor structured to drive said body to be controlled;
a sensor structured to detect position data of said body to be controlled, based on the rotational angle of said motor, at a predetermined cycle;
a servo control unit structured to servo-control said motor; and
a position control unit configured to issue an operation command (a position command) to said servo control unit;
wherein said position control unit comprises a command generating means for generating an operation command to said servo control unit, a position data storage means for storing said position data obtained from said sensor together with the obtaining time, and a position estimating means for estimating the position of said body to be controlled at a time, based on said position data taken at a predetermined cycle;
said position estimating means is configured to express the position f(t) of said body to be controlled at time t by a polynomial based on said position data to estimate the position of said body to be controlled at said time through a polynomial interpolation;
wherein said position estimating means is configured to estimate the position of said body to be controlled at said time using a third-order polynomial; and
wherein said position estimating means is configured to, based on position data at said time at which the position of said body to be controlled is estimated, estimate the position of said body to be controlled at said time.

2. The control system set forth in claim 1 wherein said position estimating means expresses the position f(t) of said body to be controlled at time t by the polynomial shown by Formula 1 below, obtains the coefficient a i of said polynomial by Formula 2 below based on said position data y i and said obtaining time t 1 , which are stored in said position data storage means;

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Assignees

• Nidec Sankyo Corp

Inventors

• Otsuji Jun
• Ito Akihiro
• Watanabe Hirokazu
• Odagiri Hideyuki

Classifications

• G05B2219/41142

  Compensation of servocontrol signals as function of changing supply voltage · CPC title

• G05D3/20 Primary

  using a digital comparing device · CPC title

• G05B19/19 Primary

  characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path · CPC title

• H02P29/02 Primary

  Providing protection against overload without automatic interruption of supply (protection against faults of stepper motors H02P8/36) · CPC title

• H02P7/06

  for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current · CPC title