Machine model predicting device of motor control device
First Claim
1. A machine model estimating device of an electric motor control apparatus comprising an electric motor for driving a load machine, a rotation detector for detecting a rotating angle of the electric motor, and a servo control device for controlling the electric motor, comprising a calculating device for outputting an operation command signal for operating the electric motor to the servo control device, and frequency characteristic equations for a rigid body model and an N-inertia model (N is an integer which is equal to or greater than 2) which are previously input to the calculating device, wherein the calculating device includes a frequency characteristic measuring section for measuring a frequency characteristic from the operation command signal and a signal of the rotation detector input from the servo control device to the calculating device, a frequency characteristic peak detecting section for automatically calculating protruded shapes to be a resonance frequency and an anti-resonance frequency from a shape of the frequency characteristic measured by the frequency characteristic measuring section, an attenuation estimation value analyzing section for estimating an attenuation from the resonance frequency and the anti-resonance frequency which are detected by the frequency characteristic peak detecting section, a frequency characteristic error calculating section for calculating errors of the frequency characteristics calculated in the frequency characteristic equation for the N-inertia model and the frequency characteristic equation for the rigid body model from the frequency characteristic obtained by the measurement respectively, and a machine model deciding section for comparing a minimum error of a calculated value of the frequency characteristic of the N-inertia model which is obtained in the frequency characteristic error calculating section and a measured value with a minimum error of a calculated value of the frequency characteristic of the rigid body model and a measured value and deciding, as an actual model, either of the models which has a smaller error.
2 Assignments
0 Petitions
Accused Products
Abstract
In an electric motor control apparatus including an electric motor 4 for driving a load machine, a rotation detector 3 for detecting a rotating angle of the electric motor 4, and a servo control device 2 for controlling the electric motor 4, a calculating device 1 automatically calculates protruded shapes to be a resonance frequency and an anti-resonance frequency from frequency characteristics obtained from an operation command signal 8 and a rotation detector signal 9, and furthermore, calculates errors of frequency characteristics calculated by frequency characteristic equations 20 for a 2-inertia model and a rigid body model from a frequency characteristic obtained by a measurement, and compares the minimum values of calculated values in the frequency characteristics of the 2-inertia model and the rigid body model and measured values respectively, thereby automatically modeling the characteristic of the machine.
Consequently, it is possible to provide a machine model estimating device of an electric motor control apparatus which can easily estimate a machine model without using an expensive measuring apparatus even if an operator has neither advanced expertise nor experiences, and furthermore, is inexpensive.
-
Citations
4 Claims
-
1. A machine model estimating device of an electric motor control apparatus comprising an electric motor for driving a load machine, a rotation detector for detecting a rotating angle of the electric motor, and a servo control device for controlling the electric motor, comprising
a calculating device for outputting an operation command signal for operating the electric motor to the servo control device, and frequency characteristic equations for a rigid body model and an N-inertia model (N is an integer which is equal to or greater than 2) which are previously input to the calculating device, wherein the calculating device includes a frequency characteristic measuring section for measuring a frequency characteristic from the operation command signal and a signal of the rotation detector input from the servo control device to the calculating device, a frequency characteristic peak detecting section for automatically calculating protruded shapes to be a resonance frequency and an anti-resonance frequency from a shape of the frequency characteristic measured by the frequency characteristic measuring section, an attenuation estimation value analyzing section for estimating an attenuation from the resonance frequency and the anti-resonance frequency which are detected by the frequency characteristic peak detecting section, a frequency characteristic error calculating section for calculating errors of the frequency characteristics calculated in the frequency characteristic equation for the N-inertia model and the frequency characteristic equation for the rigid body model from the frequency characteristic obtained by the measurement respectively, and a machine model deciding section for comparing a minimum error of a calculated value of the frequency characteristic of the N-inertia model which is obtained in the frequency characteristic error calculating section and a measured value with a minimum error of a calculated value of the frequency characteristic of the rigid body model and a measured value and deciding, as an actual model, either of the models which has a smaller error.
-
3. A machine model estimating device of an electric motor control apparatus comprising an electric motor for driving a load machine, a vibration detector for detecting a vibration of the load machine, and a servo control device for controlling the electric motor, comprising
a calculating device for outputting an operation command signal for operating the electric motor to the servo control device, and frequency characteristic equations of a rigid body model and an N-inertia model (N is an integer which is equal to or greater than 2) which are previously input to the calculating device, wherein the calculating device includes a frequency characteristic measuring section for measuring a frequency characteristic from the operation command signal and a signal of the vibration detector input from the servo control device to the calculating device, a frequency characteristic peak detecting section for automatically calculating protruded shapes to be a resonance frequency and an anti-resonance frequency from a shape of the frequency characteristic measured by the frequency characteristic measuring section, an attenuation estimation value analyzing section for estimating an attenuation from the resonance frequency and the anti-resonance frequency which are detected by the frequency characteristic peak detecting section, a frequency characteristic error calculating section for calculating errors of the frequency characteristics calculated in the frequency characteristic equation for the N-inertia model and the frequency characteristic equation for the rigid body model from the frequency characteristic obtained by the measurement respectively, and a machine model deciding section for comparing a minimum error of a calculated value of the frequency characteristic of the N-inertia model which is obtained in the frequency characteristic error calculating section and a measured value with a minimum error of a calculated value of the frequency characteristic of the rigid body model and a measured value and deciding, as an actual model, either of the models which has a smaller error.
Specification