FREQUENCY CONTROL-THE UNEXPLOITED GOLD Presentation By: John Muoka: Senior Engineer, TS

Introduction: Composition of Power System Frequency Control-The unexploited gold Introduction: Composition of Power System Major Players in Power System Power system stability-Key Parameters Mitigation against power System instability Frequency stability Voltage stability Blackout and Black start functions Frequency stability as provided by KenGen Example graphs. AGENDA: Outline

Composition of Power System: Typical Example of a Power System Frequency Control-The unexploited gold Introduction Outline Composition of Power System: Typical Example of a Power System

Power system stability-Definition Frequency Control-The unexploited gold Power system stability-Definition Outline An electric power system is a network of electrical components deployed to supply, transfer, and use electric power. Power system stability is the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance(Loss of Synchronism/Falling out of step), so that practically the entire system remains intact.

Major Players in a Power system stability Frequency Control-The unexploited gold Major Players in a Power system stability Generation Companies KenGen IPPs Transmission line operators KP KETRACO Distribution Customers

Frequency Stability Rotor angle stability Voltage Stability Frequency Control-The unexploited gold Frequency Stability Rotor angle stability Voltage Stability Power system stability-Key Parameters Outline

Why frequency control?: Causes of power System instability Frequency Control-The unexploited gold Outline Why frequency control?: Causes of power System instability Sudden change of load Switching operation Loss of generation System Faults-

Why frequency control?: Frequency Control-The unexploited gold Outline Why frequency control?: During above challenges we need units that can respond to frequency raise/dip

Why frequency control?: Frequency Control-The unexploited gold Why frequency control?: Outline

Effects of Major system instability Frequency Control-The unexploited gold Why Frequency Control? Effects of Major system instability Loss of power to customers-load shedding Damage to customer Equipment Damage to transmission equipment Damage to Generation Equipment Loss of revenue System blackout

Causes of frequency instability Loss of loads. Frequency Control-The unexploited gold Frequency stability Ability of a power system to maintain steady frequency following a severe disturbance The ability to restore equilibrium between system generation and load, with minimum loss of load or generation. Causes of frequency instability Loss of loads. Loss of generation Switching operation Switching ON/OFF big loads.

Levels of frequency control. Frequency Control-The unexploited gold Levels of frequency control. Primary frequency control by Turbine governors. Secondary frequency control by AGC. Tertiary Control: Picking plants

Levels of frequency control. Frequency Control-The unexploited gold Levels of frequency control.

Mitigation to frequency fluctuation Generating Plants Frequency Control-The unexploited gold Mitigation to frequency fluctuation Generating Plants Primary & Sec Freq. control Enough spinning reserve Grid Operator (Load shedding). Instantaneous based Rate of change of frequency Time based.

Compensation for frequency Control Frequency Control-The unexploited gold Compensation for frequency Control Frequency control is are responsibility of TSO. This is an ancillary service as per the grid code. Need for compensation by TSO to Generating companies providing this service

Frequency Control-The unexploited gold What should KenGen do Start discussions with TSO and ERC on how to be compensated on current frequency control service . Train both operations & Regulatory staff on how this service should be paid in preparation to review of PPA. Need for compensation by TSO to Generating companies providing this service Need for Future plans to include plants that can do frequency control in all stated regimes

Emergence of Wind and Solar Frequency Control-The unexploited gold Emergence of Wind and Solar Disadvantages Fluctuating power source which may cause frequency and voltage instability. Need for investment for other plants to Mitigate against frequency and voltage fluctuation. (Reserve requirements to meet reliability performance standards) Wind variability can have a significant impact on voltage profiles calling for installation of switched capacitor banks and shunt reactors

Emergence of Wind and Solar Power Plants (Issues to note) Frequency Control-The unexploited gold Emergence of Wind and Solar Power Plants (Issues to note)

Emergence of Wind and Solar Power Plants (Issues to note) Frequency Control-The unexploited gold Emergence of Wind and Solar Power Plants (Issues to note)

Emergence of Wind and Solar Power Plants (Issues to note) Power System Stability & Control Emergence of Wind and Solar Power Plants (Issues to note)

Frequency Control-The unexploited gold What KenGen has put in place in hydro plants to overcome frequency control Challenges Governor Control Modes: Load Control Mode Load Control with Frequency influence Function Pure speed control Opening control Isolated grid mode

Examples of Major Grid Disturbances-The Kenyan story. Frequency Control-The unexploited gold Examples of Major Grid Disturbances-The Kenyan story.

Frequency Control-The unexploited gold Examples of Kenyan Grid Disturbances-Mombasa Blackout.

Frequency Control-The unexploited gold Examples of Kenyan Grid Disturbances-Monkey Business at Gitaru

Power System Stability & Control Questions Thank you