JP4688653B2 - Induction machine controller - Google Patents

Description

  The present invention relates to torque control of an induction machine, and in particular, maintains the calculation accuracy of induction machine speed and makes induction machine torque control highly accurate.

FIG. 2 is a block diagram showing a conventional example. Reference numeral 1 denotes an induction machine, 2 denotes a current detector, 3 denotes a power converter, 4 denotes torque control means, 5 denotes a voltage system magnetic flux calculator, and 6 denotes a speed calculator.
The current detector 2 detects a current i flowing through the induction machine 1.

ここで、Ｒ１は誘導機１の一次抵抗、Ｌ２は二次自己インタ゛クタンス、Ｍは相互インタ゛クタンス、ＬｅｋＮは漏れインタ゛クタンス設定値である。漏れインタ゛クタンス設定値ＬｅｋＮは、

で与えられる。ここで、Ｌ１は誘導機１の一次自己インタ゛クタンスである。 The voltage system magnetic flux calculator 5 calculates the voltage system magnetic flux φv by the equation (1) from the current i and the voltage command v input to the power converter.

Here, R1 is the primary resistance of the induction machine 1, L2 is the secondary self-inductance, M is the mutual inductance, and LekN is the leakage inductance setting value. Leakage inductance set value LekN is

Given in. Here, L1 is the primary self-inductance of the induction machine 1.

ここで、Ｒ２は誘導機１の二次抵抗、ＦＡとＦＢは電圧系磁束φｖの成分である。 The speed calculator 6 calculates the induction machine speed ωm from the current i and the voltage system magnetic flux φv using the equations (3) to (5).

Here, R2 is a secondary resistance of the induction machine 1, and FA and FB are components of the voltage system magnetic flux φv.

Based on the induction machine speed ωm and the current i, the torque control means 4 outputs a voltage command v such that the magnetic flux and torque of the induction machine 1 become the magnetic flux command φ * and the torque command τ *.
The power converter 3 amplifies the voltage command v and supplies power to the induction machine 1.

  With the above configuration, the torque of the induction machine 1 can be controlled to the torque command τ *.

JP 11-069895 A

The prior art has the following problems.
In the voltage system magnetic flux calculator 5, a setting error may occur in the leakage inductance setting value LekN due to the influence of leakage magnetic flux saturation. At this time, an error occurs in the voltage magnetic flux φv, which leads to a calculation error of the induction machine speed ωm. If there is an error in the induction machine speed ωm, highly accurate torque control of the induction machine 1 by the torque control means 4 cannot be expected.
The present invention has been made to solve the above problems.

  In order to solve the above-mentioned problems, a leakage flux inductance is obtained by inputting a current flux calculator 7 for calculating a current flux φi from the current i and the induction machine speed ωm, and a voltage flux φv, current flux φi and current i. The leakage inductance identifier 8 for outputting the identification value LekN is added, and the leakage inductance identification value Lek is input to the voltage system magnetic flux calculator 5 instead of the leakage inductance setting value LekN.

  The leakage inductance of the induction machine 1 can be identified. By using the identified leakage inductance value, the calculation accuracy of the induction machine speed ωm is improved, and the induction machine 1 can be controlled with high accuracy.

  The leakage inductance of the induction machine 1 can be identified by newly adding the current system magnetic flux calculator 7 and the leakage inductance identifier 8. By inputting the identified leakage inductance value to the voltage system magnetic flux calculator 5, the calculation accuracy of the induction machine speed ωm is improved and the torque control system of the induction machine 1 is improved.

  FIG. 1 is a block diagram showing an embodiment of the present invention, in which 7 is a current flux calculator and 8 is a leakage inductance identifier.

ここで、ｊは虚数単位である。 The current system magnetic flux calculator 7 receives the current i and the induction machine speed ωm, and calculates the current system magnetic flux φi from the equation (6).

Here, j is an imaginary unit.

ここで、式（７）の「・」はベクトル内積を表し、ＧＡは同定ケ゛インである。 Leakage inductance identifier 8 receives voltage system magnetic flux φv, current system magnetic flux φi and current i, and identifies leakage inductance identification value Lek by the following equations (7) to (8).

Here, “·” in equation (7) represents a vector dot product, and GA is an identification gain.

式（９）の電圧系磁束φｖを用いて、速度演算器６において、式（３）〜式（５）で誘導機速度ωｍを演算する。 The leakage inductance identification value Lek obtained from the equations (6) to (8) is input to the voltage magnetic flux calculator 5 and used instead of the leakage inductance setting value LekN of the equation (1).

The speed calculator 6 calculates the induction machine speed ωm by the formulas (3) to (5) using the voltage system magnetic flux φv of the formula (9).

  With the above configuration, the leakage inductance of the induction machine 1 can be identified online while the torque control of the induction machine 1 is performed.

  By using the induction machine speed ωm Lek calculated using the leakage inductance identification value for the torque control means 4, the induction machine 1 can be controlled with high accuracy.

High-accuracy torque control of the induction machine becomes possible.
High-accuracy torque control is possible for an induction machine that has a large current ripple and is likely to saturate leakage inductance.

FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a block diagram showing a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Induction machine 2 Current detector 3 Power converter 4 Torque control means 5 Voltage system magnetic flux calculator 6 Speed calculator 7 Current system magnetic flux calculator 8 Leakage conductance identifier

i ... current v ... voltage command τ * ... torque command φ * ... flux command ωm ... induction machine speed φv ... voltage system flux φi ... current system flux Lek・ Leakage inductance identification value LekN ・ Leakage inductance setting value

Claims (1)

A voltage system magnetic flux calculator that calculates a voltage system magnetic flux from the current and voltage of the induction machine and a leakage inductance setting value; and a speed calculator that calculates an induction machine speed from the voltage system magnetic flux and the current, the current and the In the induction machine control device that controls the torque of the induction machine based on the induction machine speed, the magnetic flux instruction, and the torque instruction,
A current flux calculator that calculates a current flux from the current and the induction machine speed, and a leakage inductance identifier that outputs the leakage inductance identification value by inputting the voltage flux, the current flux, and the current are added. The induction machine control device, wherein the leakage inductance identification value is input to a voltage system magnetic flux calculator instead of the leakage inductance setting value.

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