tubitak uctetraining 1 1final eng

8/8/2019 Tubitak UCTETraining 1 1final ENG

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2nd UCTE project

TrainingPhase 1

Item 1Theoretical Description ofLoad-Frequency Control

Oguz YILMAZTubitak-UZAY

[email protected]


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Load-Frequency Control Primary Control (Local Control)

Secondary Control (General System

Control) Tertiary Control (Control of Minute Reserve

or Scheduled Reserve)

Time Control Example Simulations with Dynamic ModelsFor further inquiry,

http://www.entsoe.eu/resources/publications/ce/oh/

Summary
http://www.entsoe.eu/resources/publications/ce/oh/http://www.entsoe.eu/resources/publications/ce/oh/http://www.entsoe.eu/resources/publications/ce/oh/


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Control over the time line after a frequency deviation


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Primary Frequency Control

PurposeEstablishment of balance between

Generation-Load

Balance can be lost in miliseconds (breakertrip/closure)

Time is required for generation level change(seconds)

Kinetic energy change of rotating masses,=> frequency deviation

Continuous, automatic, proportional response ofgenerating units to frequency deviation

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10

units

max.

1) 7 units

1) 7 units

1) 50 units

2a) 7=>9 units (unexpected

increase in flow )

2b1) 50=>49 change in

level

2b2) 7=>9 increase in flow

2c) =>49.8 @ the new

balance

50

49

Safety

valve

Primary Frequency Control-Analogy

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Generation=Load

Generation < Load

Generation=Load

Reestablishment of the

balance between

generation&load, and a

new steady state valuefor the frequency.


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Example Simulations

Scenario 1Combined Cycle=0.97; Hydro=0.90, CoalFired=1;

Secondary Control inactive.

@ T=10.sec extra step load of 2%.

Tsim=250 sec

Scenario 2Combined Cycle=0.92; Hydro=0.90, CoalFired=0.98;

Secondary Control inactive.@ T=10.sec Extra step load of 2%.

Tsim=250 sec

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Secondary Frequency Control

PurposeEliminate frequency deviation

Maintain the interchange flows at thescheduled values

System-wide, central control over a group ofgenerating units

AGC (Automatic Generation Control)

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Ideal secondary controlafter a loss of generation


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Definitions

Control AreaEg. Turkey or Bulgaria ...

Area Control Error

ACE = Actual instantaneous net interchangescheduled netinterchange Calculated* primary control contribution

Kri => K-factor (MW/Hz) defined for the specified control area

AGC Secondary Control Parameters

+ Export

- Import

=> P, 1/Tr =I

PI Control !!!

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S d F C l


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Control Reserve

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Simulation Examples


Sekondary Control active. (only hydro)

@ T=10.sec extra step load of %2.

@ T=250.sec extra step load of %1Tsim=600 sec


Sekondary Control active. (hydro+combined cycle)@ T=10.sec extra step load of %2.

@ T=250.sec extra step load of %1

Tsim=600 sec

[email protected]


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Tertiary Frequency Control

PurposeProvision of reserve continuity for SecondaryControl (scheduled activation)

For large incidents, provision of secondaryreserve (direct activation) (minute-reserve)

Distribution of Control Reserve among

generating units or committed units,depending on ECONOMY and SAFETY

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Tertiary Control

G ti L d U b l


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Geneation-Load Unbalance

and Control over the Time axis


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Example Simulations

Scenario 5Combined Cycle=0.92; Hydro=0.90, CoalFired=0.98;Secondary Control active. (hydro + combined cycle)



@T=700.sec Tertiary Reserve 1 is being activatedTsim=1200 sec


Secondary Control active. (hydro + combined cycle)



@T=700.sec Tertiary Reserve 1 is being activated (0.45 pu)

@T=1200. sec Tertiary Reserve 2 is being activated (0.45 pu)

Tsim=2000 [email protected]


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Time Control

Purpose

When fgerek not controlled with quality andintegral error increases,

fset set different than 50 Hz to minimizeintegral error.

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Example Simulations

Scenario 7Between T=2000. sec and T=2400. sec, time control

fset=50.05

Tsim=2500 sec.

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Emergency Control

Purpose

In case generation-load unbalance can notbe maintained with 3-stage control,reestablisment of balance with unpreferred

methodsUnder frequency load-shedding

Instantaneous Demand Control (new approach)

Generation TrippingConfiguration change at plant load controlsystems (deactivation of load controllers,limiters)

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Simulation Examples


Secondary Control active. (hydro + combined cycle)



@T=700.sec Tertiary Reserve 1 is being activated (0.45 pu)

@T=1200. sec Tertiary Reserve 2 is being activated (0.45 pu)

Time control between T=2000. sec and T=2400. sec

@T=2700.sec extra load of %10 begins to activate.

Tsim=3500 sec.

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tubitak uctetraining 1 1final eng

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