Regulation of electric drives coordinates

Two important relative functions lies upon the electric drive:

- Electromechanical transformation of energy;

- Control of the manufacturing method setting.

Technological demands defines the necessity of specifying and keeping at right accuracy at specified level those, or another mechanical variables on definite stages:

- Position of operating mechanism;

- Speed of operating mechanism;

- Acceleration;

- Motor moment;

- Load, etc;

Also technological demands define the conditions of changing of these parameters.

Depending on the problems of electric drive and operating mechanism control the coordinate regulation may be realized with the purpose of:

- Maintaining of specified level of variables;

- Change of variable by required law;

- Limitation of variables by legitimate value;

- Developing of arbitrary motion laws that are specified on system input with the required accuracy (follow-up motor);

Possible methods of electric drive variables control are divided in two groups:

- Parametrical control methods used in open loop control systems;

- Methods of automatic coordinate regulation due to feedback couplings (in the locally-closed and closed control systems).

This problems will be considered in the “Automatic electric drive conrol” part.

In such a way basic electric drive motion control for execution of technological process defines the necessity in regulation of electromechanical system variables – the coordinates of electric drive.

The necessity of electric drive coordinates regulation is defined by process requirements, with this the selection of efficient regulation method from a several available methods is an important problem which is solved when designing of electric drive.

For realization of such selection the basic generalized regulation features should be known:

- Accuracy of regulation;

- Range of regulation;

- Smoothness of regulation;

- Stability;

- Direction of regulation;

- Tolerated load in the range of regulation, quick response, oscillationary, overregulation;

- Efficiency of regulation.

Consider these regulation features in the example of speed regulation.

4.1 Basic Generalized Indexes of Electric Speed Regulation

When operating of different operating mechanism occurs the necessity in regulation of speed, specified first of all by necessity of rationality provision of technological process carrying out.

These mechanisms should be considered as the mentioned above mechanisms:

- Metal-working machinery;

- Lifting-transport mechanisms;

- Rolling mills;

- Transport, etc.

Speed regulation shouldn’t be confused with the natural changes of speed that occurs in ED, when changing the load on the operating part of mechanism.

Therefore:

Дата добавления: 2014-01-05