DD228121A1 - CIRCUIT ARRANGEMENT FOR BLIND LOAD DISTRIBUTION IN PARALLEL OPERATION OF SYNCHRONOUS GENERATORS WITH DIFFERENT EXTRACTION CIRCUITS - Google Patents

Abstract

Circuit arrangement for reactive load distribution in parallel operation of synchronous generators with different exciter circuits in self-contained networks. By the circuit arrangement is to be achieved, that despite the different excitation circuits, the requirements are met to the dummy load distribution. For this purpose, the generator currents are detected, subtracted in the correct phase and generates a voltage proportional to the difference of the reactive currents. With the help of this voltage, the excitation of one generator is controlled so that the difference of the reactive currents reaches a minimum. This circuit arrangement applies to retrofits and modifications of power generator networks in which generators of the same type of excitation can not be used. Fig. 1

Description

Title of the invention;

Circuit arrangement for reactive load distribution in parallel operation of synchronous generators with different Erreserschaltunken.

In the case of the invention

The S _r invention relates to the control of reactive load distribution of an electric ITetzes obtained by zv; is gespeisü egg or more parallel working 'Field generators with different exciting circuits.

Characteristic of the known technical solutions

In known power generator systems with high voltage compulsory energizing means (resin circuit) of generators, it is common to use compensating lines for symmetric reactive load distribution. Prerequisite for the use of such iusgleichsleitungen are the same

Generators with electrically or electronically controlled excitation devices, the principle of Aususgleichsleitungen is not applicable, so dai3 the reactive load distribution must be controlled by the Spannungsatatik. A parallel operation of generators with excitation according to the principle of Plarz's circuit and those with an electrically or electronically controlled exciter lsi; due to the non-compensating voltage statics, or only with high-impedance / and by creating an impedance imitation

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possible with subordinate control device. The required circuit complexity is therefore very expensive for power generator systems on ships.

Object of the invention.

The aim of the invention is a circuit arrangement for controlling the reactive load distribution "with parallel operation of generators with different voltage stability and control Prinaip the Srregerspannung, as is possible in particular for retrofits or modifications of generators generators

Exposition of the 77ea ^; ens of 'invention

The invention has for its object to provide a circuit arrangement Su, in the application of a proper parallel operation of generators with different Erregerschaltuing is realized and the requirements are met with respect to the dummy load distribution. According to the invention, the object is achieved on the basis of a constant generator voltage J in that the apparent current, which is a proportional magnitude for the apparent power, is detected and evaluated by each generator. The Scheinström® of the generators with current, voltage compulsory excitation control (Harzsche detection) are summed or evaluated by a selection circuit. The thus obtained current value with the associated phase position is fed to a mixing point. Between these and the also pending with a phase angle apparent current of the generator with electrical or electronic control of the excitation voltage, the difference of the currents is formed, which is fed via a current-voltage converter to a phase-sensitive rectifier, at whose output a DC voltage is produced, their sign and amplitude depends on the phase difference and magnitude of reactive currents. This DC voltage is the regulator

supplied to the electrical or electronically controlled generator and the setpoint voltage superimposed so that a balancing takes place to the minimum of the differential reactive current. Thus, a symmetrical or by weighting "of the generator currents predetermined reactive current distribution and a suppression of the reactive compensation currents between the generators with regulators and those with current, voltage forced-compounding exciter is achieved.

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ίηαand a iusführungsbeispiels the invention will be explained. According to Figure 1, two generators with current, voltage compelling excitation '(generator 2) whose exciter winding is connected in parallel via a iusgleichsleitung and a generator with electronically controlled Srregereinrichtung (generator I) ₅ operate in parallel operation, the usual Jetsbelastung causes a phase angle with a cos. ^ RI.

weighted and fed to the mixing point ό . The current I. of the electronically controlled generator ι becomes

1 "

detected by the measuring element 3, gewicntet and fed to the mixing point 5. The polarity of the currents of the generators 1 and 2 is such that in the mixing point 5 of the differential current Σΐ_ and 2Inn is formed. This difference current δ I becomes a Stcm voltage converter 6 and on

is switched so that it is a part of the

whose polarity depends on the phase angle of the 31inds ~ novel part of δ I.

This DC voltage is used as a control voltage and the set value of the electrical voltage regulator is switched so that an influence of the resulting SoIlvvertspannung done in the sense that by controlling the excitation voltage of the generator Ί the reactive current component

of the differential current δ I from the mixing point Ό is adjusted to the value ' ¹ IfUlI' or, 'minimum *. Thus, the Blindausgleiciisstrom between the genera-, gates 1 and 2 to Hull and the reactive current of the electrical network is divided according to the weighting in a predetermined form to the generators.

If, according to FIG. 1, two generators 1 and several generators 2 operate in parallel with an electrical heater, then a generator 1 is defined as a guiding machine for the generator group 1. The detected via the measuring element 'current I this guide generator is placed on the mixing points 5 and 11. The current 1 of the other generator 1 is also fed to the mixing point 1. In the mixing point 1 there is a difference between the currents I of the generators 1, the difference current δ I from the mixing point 1 is then applied via a current-voltage converter 6 a phase-sensitive rectifier 7 which generates a control voltage whose amplitude and polarity is proportional to the size and phase of the differential reactive current δ I from mixing point 1. This voltage adjustment is applied to the voltage setpoint of the electronic voltage regulator of the generator 1 (driving generator) so that the excitation voltage is It is thereby controlled that the reactive current component of the differential current Δ 1 of the mixing point 1 becomes Hull or to a minimum, thereby ensuring that both generators 1 have reactive currents corresponding to the weighting, in the phase position and amplitude associated phasing between the generators 1 and 2 takes place as explained above.

Claims (4)

Brfindungsanssruch 1. Circuit arrangement for reactive load distribution in parallel operation of synchronous generators, of which the output voltage can be controlled by an external signal at least in one generator, characterized in that the a-output current of the generator (i) and the output current of the generator (2) detected, by a mixing point (5) the difference of the currents is formed and m λ ~ u xi j -i »x © oi_ii.ss ο '^ ^ - * ο li-i. * ~ ώ ο s ι! ii ui η ^ s * Λ '3 η G j »c χ ¹ s ic), s ο * λ' χ θ g ι η 3 ώ phase-sensitive rectifier (7) a control voltage proportional to the difference of the reactive currents is generated with whose assistance the control variable of the controller (3) of the controllable generator (i) is to be changed so that the difference of the reactive currents reaches their Minimuni. 2. The circuit arrangement according to item 1, characterized in that several not externally controlled generators (2) operate in parallel by known methods, wherein the measuring element (4) assigned to each generator and the measured variables of a selection circuit (10) supplied and the selected measured variable on mixing point (5 ) is given. 3. Circuit arrangement according to item 1 and 2, characterized in that the selection circuit (10) is replaced by a circuit which detects the measured variable of all the IJetz generators (2) and their average value of the lennstrom related measured value to the mixing point (5) is switched. 4. Circuit arrangement according to item 1 and 2 or 3, characterized in that j, that a plurality of externally controlled generators toren (ι) work in parallel, each generator (1) a measuring element 3 and each other generator (1) a
Assigned mixing point (11) and the iusgangssignal the water mixing point (11) via a current-voltage converter (6) and a phase-sensitive rectifier (7) au the associated generator (1) is switched. For this 1 page drawings