TechRef_PowerFrequencyCtrl.pdf

DIgSILENT PowerFactory Technical Reference Documentation

Power-Frequency Control ElmSecctrl

DIgSILENT GmbH Heinrich-Hertz-Str. 9 72810 - Gomaringen Germany T: +49 7072 9168 0 F: +49 7072 9168 88 http://www.digsilent.de [email protected] Version: 2016 Edition: 1

Copyright © 2016, DIgSILENT GmbH. Copyright of this document belongs to DIgSILENT GmbH. No part of this document may be reproduced, copied, or transmitted in any form, by any means electronic or mechanical, without the prior written permission of DIgSILENT GmbH. Power-Frequency Control (ElmSecctrl)

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Contents

Contents 1 Power-Frequency-Control

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1.1 Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1.2 Definition of a Power-Frequency-Control Element . . . . . . . . . . . . . . . . . .

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1.3 Usage Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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List of Figures

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Power-Frequency Control (ElmSecctrl)

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Power-Frequency-Control

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Power-Frequency-Control Concept

The task of the Power-Frequency-Control is to set the active power balance as typically done by secondary control. If an unbalance between the scheduled active power values of each generation unit and the loads plus losses occurs, primary control will adapt (increase/decrease) the active power production of each unit, leading to an over- or under-frequency situation. The secondary frequency control will then control the frequency back to its nominal value, reestablishing a cost-efficient generation delivered by each unit. Please consider that the Power-Frequency-control only will be active if the load-flow calculation setup dialog, Sub-page “Active Power Control” is using According to Secondary Frequency Control.

1.2

Definition of a Power-Frequency-Control Element

Please multi-select the active power sources (synchronous machines) and the bus whose frequency should be controlled. Remember that a multi-select is made by (left-)clicking the first element (e.g. the bus) and keeping the Control key pressed while clicking on the remaining elements (e.g. the synchronous generators). The dialog as shown in Figure 1.1 should appear.

Power-Frequency Control (ElmSecctrl)

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Power-Frequency-Control

Figure 1.1: Power-Frequency Control Dialogue

The options to be set in this dialogue are the following: Control Area Exchange Two different modes can be selected for the active power control • Frequency Control The global frequency in the system is controlled by the units listed • Power-Frequency-control The active power exchange of the zone the bus mentioned belongs to is controlled. Please see the Manual for a description how to define zones. Bus bar of Frequency Measurement Bus defining the zone (Power-Frequency-Control) or bus with direct frequency measurement (Frequency Control). Area Exchange Power Set Point (Only Power-Frequency Control) Set Point for the zone active power exchange. Frequency Bias (Only Power-Frequency Control) Droop for correction of active power exchange in case of frequency deviations. Power-Frequency Control (ElmSecctrl)

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Power-Frequency-Control

Control Mode Contribution of the different active power sources in controlling the frequency. The percentage of each source to feed an actual value different from its set point can be set according to two different options • According to Nominal Power The contribution will depend on the rating of the device • Individual active power The percentage of each contribution can be set individually. The sum always will be calculated to 100%.

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Usage Hints

Like for the station control, the Power-Frequency-Control is a PowerFactory element that cannot be found in the graphic. However it is a specific calculation element, that is also listed when . It icon is shown as . If you experiselecting the icon Objects relevant for the calculation ence problems with the Power-Frequency control, you may please check that you did not define multiple Power-Frequency controllers for the same bus or zone, as these may result in conflicts during the calculation.

Power-Frequency Control (ElmSecctrl)

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List of Figures

List of Figures 1.1 Power-Frequency Control Dialogue . . . . . . . . . . . . . . . . . . . . . . . . . .

Power-Frequency Control (ElmSecctrl)

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