JP2001211697A - Motor controller without speed sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of need for estimating an initial resistor exactly because errors occur at initial speed and initial secondary magnetic flux estimated value, in performing torque control of a motor under stopping or inertial rotation with a device having no sensor. SOLUTION: A primary resistor identifying means for identifying a primary resistor is provided newly, and a primary resistor identified for the initial value estimating device is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to torque control of a motor, and more particularly to a technique for estimating an initial speed and an initial secondary magnetic flux of a motor with high precision, and for controlling motor torque with high precision.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing an example of the prior art, in which 1 is a torque control means, 2 is a pickup control means, 3 is a switching device, 4 is a power converter, and 5 is a current detecting means. , 6 is an electric motor, and 7 is an initial value estimator. The current detector 5 detects a current vector i flowing through the electric motor 6.
The pick-up control means 2 receives the current vector i detected by the current detector 5 and outputs a pick-up voltage command v0 for converting the current i flowing through the motor 6 to DC.

An initial value estimator 7 receives a current vector i, a pick-up voltage command v0, a pick-up control start command ST, and a primary resistance R1, and inputs an initial speed ωm0 and an initial secondary magnetic flux φ20.
Is output.

When the torque control start command SW is set, the torque control means 1 outputs an initial speed ω which is an output of the initial value estimator 7.
A torque control voltage command V1 for controlling the torque of the electric motor 6 is output based on the current vector i using m0 and the initial secondary magnetic flux φ20 as initial values.

The switching unit 3 switches between a pickup voltage command v0 and a torque control voltage command V1 according to a torque control start command SW. That is, the pickup voltage command v0 is set as the voltage command V * until the torque control start command SW is set, and the torque control voltage command V1 is output as the voltage command V * when the torque control start command SW is set. Power converter 4 amplifies voltage command V * and supplies electric power to electric motor 6.

With the above configuration, the pickup control means 2 and the initial value estimator 7 estimate the initial speed ωm0 and the initial secondary magnetic flux φ20 of the electric motor 6 until the torque control start command SW is issued. When the torque control start command SW is set,
Initial speed ωm0 and initial secondary magnetic flux φ2 at the time when SW is turned on
With 0 as an initial value, torque control of the electric motor 6 is performed.
The timing for issuing the torque control start command SW is as follows.
Pickup control time, initial velocity ωm0 and initial secondary magnetic flux φ2
Decide from 0 state.

Hereinafter, the pickup control until the torque control start command SW is issued will be described in detail.

As one configuration of the pick-up control means 2, as shown in FIG. 4, a pick-up voltage command v0 for controlling a current flowing through the motor 6 to DC from a DC current command I, a current phase angle θ, and a current vector i is output. Some of the current control means 8 are provided. The initial value estimator 7 estimates the initial speed ωm0 and the initial secondary magnetic flux φ20 of the electric motor 6 from the movement of the pickup voltage command v0. FIG. 5 is a configuration example of the initial value estimator 7. 9 is an actual magnetic flux estimator, 10 is an actual magnetic flux memory,
11 is an actual magnetic flux extractor, 12 is an initial speed estimator, 13 is an initial magnetic flux estimator, and 14 is a calculation timer.

The operation timer 14 is a timer counter that is cleared to 0 at the edge of the pickup control start command ST, and outputs a pickup time t0. The actual magnetic flux estimator 9 is
Current vector i, pick-up voltage command v0, primary resistance R1
Is used to calculate the actual magnetic flux estimation vector φ2r from equation (A). Here, L1 is a primary self inductance, L2 is a secondary self inductance, and M is a mutual inductance.

The actual magnetic flux memory 10 stores a section 0 to t0 of the actual magnetic flux estimation vector φ2r that changes every moment. The real magnetic flux extractor 11 calculates the values of the real magnetic flux estimation vector φ2r at arbitrary three points φ (t00) and φ (t00) from the interval 0 to t0.
1) Extract φ (t02).

The initial speed estimator 12 calculates the initial speed ωm0 according to equations (B) to (G), for example. First, the center R of a circle passing through three points is determined by equations (B) to (E). Here, (F1A, F1B), (F2A, F2B),
(RA, RB) are the components of F1, F2, and R, respectively. Next, φ (t00) and φ (t0) viewed from the center R of the circle
The angle θC in 2) is obtained by Expression (F). Finally, the initial speed ωm0 is obtained by the equation (G).

The initial magnetic flux estimator 13 obtains an initial secondary magnetic flux φ20 by the equation (H). Here, j is an imaginary unit, T2 is a quadratic time constant, and L2 / R
2 obtained. R2 is a secondary resistor.

[0013]

In the prior art,
There are the following problems. If there is an error in the primary resistance R1 due to a change in the motor temperature or the like, the error of the calculated magnetic flux vector φ2r, which is the output value of the real magnetic flux calculator 9, is integrated by Expression (A). As a result, the output φ of the actual magnetic flux extractor 11 is φ
(Tx0), φ (tx1), and φ (tx2) have errors. Errors occur in the initial velocity ωm0 and the initial secondary magnetic flux φ20 estimated by the equations (B) to (H) based on φ (tx0), φ (tx1), and φ (tx2).

As described above, if there is an error in the primary resistance, an error occurs in the initial speed ωm0 and the initial secondary magnetic flux φ20, and the initial value of the torque control means 1 has an error. Can't do it. The present invention
This is to solve the above problems.

[0015]

An R1 identifier for inputting a current vector i, a pickup voltage command v0 and a pickup control start command ST is newly added, and the output value of the R1 identifier is set as a primary resistance R1.

In the second aspect, the R1 identifier has the following configuration. An identification timer that clears the output value to 0 at the edge of the pickup control start command ST and counts up the identification time tx. A magnetic flux calculator that inputs a current vector i, a pickup voltage command v0, and a primary resistance nominal value R1C and outputs a calculated magnetic flux vector φ2s. An operation magnetic flux memory for storing the operation magnetic flux vector φ2s at the time tx. An operation magnetic flux extractor that extracts operation magnetic flux vectors at arbitrary multiple points from the operation magnetic flux memory. Arithmetic magnetic flux vector and current vector i at arbitrary multiple points in time
And a primary resistor R1 is output.

By the above means, the primary resistance fluctuation can be identified, and the actual magnetic flux estimation vector estimated by the actual magnetic flux estimator can be obtained with high accuracy. As a result, the initial speed and the initial secondary magnetic flux of the motor can be estimated with high accuracy, and the motor torque can be controlled with high accuracy.

[0018]

FIG. 1 is a block diagram showing an embodiment of the present invention, and reference numeral 20 denotes an R1 identifier. The R1 identifier 20 receives the pickup control start command ST and the current vector i.
And a pickup voltage command v0, and outputs a primary resistance R1 as an input value of the initial value estimator 7. The addition of the R1 identifier 20 enables the fluctuation of the primary resistance R1 to be identified, and the actual magnetic flux estimation vector φ2r estimated by the actual magnetic flux estimator 9 to be obtained with high accuracy. As a result, the initial speed ωm0 of the motor 6 and the initial secondary magnetic flux φ20
Can be estimated with high accuracy, and the motor torque can be controlled with high accuracy.

FIG. 2 shows an example of the configuration of the R1 identifier 20, wherein 21 is an identification timer, 22 is a magnetic flux calculator, 23 is an arithmetic magnetic flux memory, 24 is an arithmetic magnetic flux extractor, and 25 is an R1A identifier. .

The identification timer 21 is a timer counter that is cleared to 0 at the edge of the pickup control start command ST, and outputs an identification time tx. The magnetic flux calculator 22 calculates the calculated magnetic flux vector φ2s from the current vector i, the pick-up voltage command v0, and the primary resistance nominal value R1C by the equation (I).

The calculation magnetic flux memory 23 stores the 0 to tx section of the calculation magnetic flux vector φ2s that changes every moment. The operation magnetic flux extractor 24 calculates the values φs (tx0), φs of the operation magnetic flux vectors φ2s at three equally spaced intervals from the 0 to tx section.
(Tx1) and φs (tx2) are extracted. In particular, tx2
Is the identification time tx, And put.

The R1A identifier 25 generates φs (tx0), φ
s (tx1), φs (tx2), identification time tx, current vector i, and primary resistance nominal value R1C are input, and primary resistance R1 is output. Hereinafter, the R1A identifier 25 will be described.

In the formula (I), the primary resistance nominal value R
It is assumed that 1C deviates from the true value R1 by an error ΔR. When the equation (K) is substituted into R1C of the equation (I), the current vector i is constant, so the equation (I) is expressed by the equation (L) using the equation (A). Here, t is the calculation time of φ2s. Also, L2 ≒ M
And

Therefore, E0 is calculated by the equations (M) to (O). Here, E0A and E0B are coefficients when E0 is summarized for ΔR.

Since φ2r draws a circle, the origin, FS1, and F2
S2 is on the same circle. Furthermore, the origin, FS1 and FS2
Are sampled at equal intervals, so that E0 is 0. Here, the primary resistance R1 is expressed by the equation (P) satisfying E0 = 0.
However, the denominator of the equation (P) may be 0, and at this time, the primary resistance R1 becomes indefinite. Therefore, the primary resistance R1 is identified by using an integral instead of the direct calculation from the equation (P).

The integral identification method is represented by equations (Q) to (S). Here, GR1A is the identification gain, and B0 is Δ in the previous calculation.
R value. It is assumed that B0 = 0 at t = 0. Hereinafter, the primary resistance R1 can be obtained by the equation (K).

[0027]

According to the present invention, the primary resistance fluctuation can be identified. As a result, the initial speed and the initial secondary magnetic flux of the motor can be estimated with high accuracy, and the motor torque control can be performed with high accuracy, which is very useful in practice.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration example of an R1 identifier according to the present invention.

FIG. 3 is a block diagram showing one conventional example.

FIG. 4 is a block diagram showing an example of a configuration of a conventional pickup control means.

FIG. 5 is a block diagram showing a configuration example of an initial value estimator according to a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 torque control means 2 pickup control means 3 switch 4 power converter 5 current detector 6 motor 7 initial value estimator 8 current control means 9 real magnetic flux estimator 10 real magnetic flux memory 11 real magnetic flux extractor 12 initial speed estimator 13 Initial magnetic flux estimator 14 Operation timer 20 R1 identifier 21 Identification timer 22 Magnetic flux calculator 23 Operation magnetic flux memory 24 Operation magnetic flux extractor 25 R1A identifier v0 Pick-up voltage command V1 Torque control voltage command V * Voltage command i Current vector SW Torque control start command ST Pickup control start command R1 Primary resistance ωm0 Initial speed φ20 Initial secondary magnetic flux I DC current command θ Current command phase angle t0 Pickup time φ2r Actual magnetic flux estimation vector φ (t0) Actual magnetic flux estimation vector at time t0 t00, t01, t02 Any value between 0 and t0 inclusive φ (t00) t Actual magnetic flux estimation vector at time 0 φ (t01) Actual magnetic flux estimation vector at time t01 φ (t02) Actual magnetic flux estimation vector at time t02 tx Identification time φ2s Operation magnetic flux vector R1C Primary resistance nominal value φs (tx) Operation magnetic flux at time tx Vector tx0, tx1, tx20 Arbitrary value between 0 and tx inclusive φs (tx0) Arithmetic magnetic flux vector at time tx0 φs (tx1) Magnetic flux vector at time tx1 φs (tx2) Magnetic flux vector at time tx2

Claims (2)

[Claims] 1. A current detector for detecting a current vector flowing in a motor, a pick-up control means for inputting the current vector and outputting a pick-up voltage command for flowing a DC current to the motor, the current vector and the pick-up voltage command And a primary resistance and a pick-up control start command, a speed sensorless motor control device having an initial value estimator for outputting an initial speed and an initial secondary magnetic flux, wherein the current vector, the pick-up voltage command, and the pick-up control start command A speed sensorless motor control device, characterized by newly adding an R1 identifier for inputting the following equation, and using an output value of the R1 identifier as the primary resistance. 2. An R1 identifier which receives an identification timer for counting up an identification time tx by the pickup control start command, inputs the current vector, the pickup voltage command and a primary resistance nominal value, and outputs an arithmetic magnetic flux vector. A magnetic flux calculator that calculates the magnetic flux vector at time tx, a magnetic flux memory that stores the magnetic flux vector at time tx, a magnetic flux extractor that extracts a magnetic flux vector at any of a plurality of times from the magnetic flux memory, R1 for inputting a magnetic flux vector and the current vector and outputting the primary resistance
The speed sensorless motor control device according to claim 2, comprising an A identifier.