DE3222271A1 - Method for controlling and regulating a synchronous machine - Google Patents

Abstract

In a method for controlling and regulating a synchronous machine which is operated on the converter and has indirect flux orientation, that is to say the flux position which is required for control being calculated from the rotor position and from the reference variables for the currents, and the components of the actual flux value being additionally determined from the terminal voltage and current, the object exists of compensating for errors in the rotor model when calculating the reference variables for the angle delta as well as the reference variable for the excitation current iE, by regulation. This is achieved by the co-ordinates ( psi m, psi l) of the actual flux value ( psi alpha , psi beta ) being determined with respect to the previously calculated position of the flux using a co-ordinate rotator (3'), by the deviation in the m-component of the flux vector from the reference value psi being supplied to a first flux regulator (11a) whose output signal is subtracted from the reference value of the stator current component in the magnetisation direction (Ism) which is supplied to the rotor model, that is to say to the device for calculating the reference values for the angle delta between the flux and rotor axes and for the excitation current iE (2), while the reference variable for the stator current component in the magnetisation direction (Ism) impressed on the machine remains uninfluenced, and by the deviation in the 1-component of the flux from the value zero being supplied to a second flux regulator (11b), whose output signal is subtracted from the reference value of the stator current component at right angles to the magnetisation direction (isi), which is supplied to the rotor model, while the reference variable for the stator current component at right angles to the magnetisation direction (isi), which is impressed on the machine, remains uninfluenced. <IMAGE>

Description

Process for control and regulation

of a synchronous machine The invention relates to a method for controlling and regulating a synchronous machine operated on the converter in accordance with the preamble of the present claim.

The part of the structure which is of interest here is assumed with reference to FIG. 1 a device for guiding a synchronous machine with the help of indirect flux orientation shown as described in German patent application P 30 45 032.9 became.

In current model 1, the reference variables for the components of the Stator current in the direction of flow i sm (to influence the cozy) and perpendicular to it i51 (for adjusting the torque) from the reference variables for torque M, Flux 9 and formed for the phase angle # between machine voltage and current. In runner model 2, from the reference variables i5 1 ism Isl for the angle (the probable Angle between flux and rotor axis) its angular functions sin #, cos g calculated; as well as the reference value for the excitation current iE. E With the help of a coordinate turner 3 (cf. the dissertation by Dipl.-Ing. Felix Blaschke "The process of field orientation for the regulation of the rotating field machine ", Faculty of Mechanical and Electrical Engineering of the Technical University Carolo-Wilhelmina in Braunschweig, and the essay from "Control in Power Electronics and Electrical Drives", edited by W. Leonhard, Braunschweig / FRG, Volume 1, 1974 VDI / VDE Society for Measurement and Control Technology, Pages 681 to 695) can be obtained from the information cos ) ~, sin Xand each- nigen from the runner model cos g, sin g the che Flux position can be determined in the form of the angle information cos. With the help of now available reference variables flux position, current components is i51 and excitation current iE as well as that of the machine control 5p6 and the converter 7,8 can be an impression of the strand currents iR, is, iT and iE into the machine 9 according to the T E flow-oriented Principle.

The invention is based on the problem of eliminating the errors in the rotor model when calculating the reference variables for the angle and the reference variable for to compensate the excitation current iE by a regulation.

The task is given by the claim in the characterizing part of the present listed process steps ge solves.

The method according to the invention is based on the soft nüng in the Embodiments described below explained in more detail.

In Fig. 2 with 1 to 9 the same devices as in Fig. 1 referred to.

With the help of a flux calculator (10) the terminal voltage becomes and an actual flux value with the components (# α, # ß) is determined for the line currents. With the help of a coordinate turner 3 ', the column-related coordinates the actual value of the flux pointer (# α, # ß) and the pre-calculated as reference variable Flux position cos #, sin # the components W m # 1 of the actual flux pointer with respect to the Setpoint coordinates determined. The difference to the flow control variable (f, 0) is determined and component-wise fed to two PI controllers 11a, 11b (first and second flow regulator). It should be noted that the reference variable for the flow component Wl is zero.

The controller output could now, in order to influence the flow, to the Reference variables for the current components i sm and isl are added because the flow is, only delayed by the action of the damper, the sum of the injected currents proportional. However, influencing the stator current components i sm, isl-would result in a changed phase angle y (cozy) or a changed torque.

According to the invention, therefore, the controller outputs do not become the reference variables for the stator currents actually flowing in the machine added, rather than from subtracts supplied to the model. So it becomes the output signal # ism of the controller lla subtracted from the stator current component in the magnetization direction i sm and the value obtained in this way is fed to the rotor model 2.

Furthermore, the output signal A sm of the controller 11b is derived from the stator current component subtracted perpendicular to the direction of magnetization i51 and the value thus obtained fed to the rotor model 2.

The command values for the stator current components impressed on the machine ism, is to remain unaffected.

The result is an influence on the reference variables for the angle S and the excitation current iE. This causes the setpoint and actual value of the flux pointer according to phase position (influencing the angle df) and amount (influencing iE) can be brought into congruence by the intervention of the inventive scheme.

If the flow computer 10 is not a meaningful output at low speeds signal, the flow regulators are automatically blocked.

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Claims (1)

Claim method for controlling and regulating a converter at the converter operated synchronous machine with indirect flux orientation, i.e. the calculation the flux position required for control from the rotor position and the reference variables for the currents and an additional determination of the components of the actual flow value from terminal voltage and current, characterized in that with the aid of a coordinate rotator (3 ') the coordinates (tm Wl) of the actual flow value (») with respect to the precalculated Location of the river can be determined that the deviation of the m-component of the flux vector is fed from the reference value # to a first flow controller (11a), the output signal of which the guide value of the runner model, i.e. the device for calculating the guide values for the angle g between the flux and rotor axes and for the excitation current E (2) Stator current component in direction of magnetization (ism) subtracted while the reference variable for the stator current component impressed on the machine in magnetization direction (is) remains unaffected, and that the deviation of the I-component of the flow of value zero is fed to a second flow regulator (alb) whose output signal is based on the reference value of the stator current component supplied to the rotor model perpendicular to the magnetization direction (is) is subtracted, while the reference variable for the stator current component impressed on the machine perpendicular to the direction of magnetization (is) unaffected lead.ot.