The basic Load Frequency Control (LFC) block diagram of an isolated power system is shown below:...

  

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The basic Load Frequency Control (LFC) block diagram of an isolated power system is shown below: Power Reference Governor Governor Droop Turbine Load Change Generator & Frequency Dependent Load Frequency Figure 1: LFC for isolated power system The data required for developing the Simulink model are given below: Generator: Use a linearized model of the generator with moment of inertia of the rotating mass equal to H (recall M= 2H). Turbine: The turbine model is approximated using first order transfer function with time constant TCH. Governor: Governor senses frequency of the system and controls the output of generator. The governor model is a linear model with time constant Tc. The speed regulation of the governor R determines the change in unit's output for a given change in frequency. Load Model: The power system load consists of both non-frequency and frequency sensitive loads. D is expressed as percent change in load divided by percent change in frequency which represents the frequency dependent loads in the system. Supplementary control for Single Area System: Once load change occurs, the supplementary controller must act to restore the frequency to nominal value. In this 3. Laboratory Tasks and Reports: Problem Statement: Use the following parameters for the power station: Governor time constant T = 0.25 sec Turbine time constant TCH. = 0.5 sec Generator inertia constant H = 8 sec Governor speed regulation R = 0.04 p.u. The load varies by 1.6 percent for a 1 percent change in frequency. The turbine rated output is 200 MW at nominal frequency of 60 Hz. Use a sudden load change of 25% for analyzing the results. i) Design an LFC (Simulink model) using the configuration shown in Figure 1. ii) Analytically find the value of the steady-state frequency deviation (Aws) that you would get without the supplementary control action. Compare the results with the results with the results from the Simulink model results. iii) Next, add the supplementary control branch in the Simulink model and run the simulation. Set the integral controller gain K, value for satisfactory performance. Record the result and compare with those found in part (ii). Power Reference Governor Governor Droop Turbine Supplementary Control (K/s) Load Change Generator & Frequency Dependent Load Frequency Figure 2: Supplementary Control Loop added to LFC for isolated power system. The basic Load Frequency Control (LFC) block diagram of an isolated power system is shown below: Power Reference Governor Governor Droop Turbine Load Change Generator & Frequency Dependent Load Frequency Figure 1: LFC for isolated power system The data required for developing the Simulink model are given below: Generator: Use a linearized model of the generator with moment of inertia of the rotating mass equal to H (recall M= 2H). Turbine: The turbine model is approximated using first order transfer function with time constant TCH. Governor: Governor senses frequency of the system and controls the output of generator. The governor model is a linear model with time constant Tc. The speed regulation of the governor R determines the change in unit's output for a given change in frequency. Load Model: The power system load consists of both non-frequency and frequency sensitive loads. D is expressed as percent change in load divided by percent change in frequency which represents the frequency dependent loads in the system. Supplementary control for Single Area System: Once load change occurs, the supplementary controller must act to restore the frequency to nominal value. In this 3. Laboratory Tasks and Reports: Problem Statement: Use the following parameters for the power station: Governor time constant T = 0.25 sec Turbine time constant TCH. = 0.5 sec Generator inertia constant H = 8 sec Governor speed regulation R = 0.04 p.u. The load varies by 1.6 percent for a 1 percent change in frequency. The turbine rated output is 200 MW at nominal frequency of 60 Hz. Use a sudden load change of 25% for analyzing the results. i) Design an LFC (Simulink model) using the configuration shown in Figure 1. ii) Analytically find the value of the steady-state frequency deviation (Aws) that you would get without the supplementary control action. Compare the results with the results with the results from the Simulink model results. iii) Next, add the supplementary control branch in the Simulink model and run the simulation. Set the integral controller gain K, value for satisfactory performance. Record the result and compare with those found in part (ii). Power Reference Governor Governor Droop Turbine Supplementary Control (K/s) Load Change Generator & Frequency Dependent Load Frequency Figure 2: Supplementary Control Loop added to LFC for isolated power system.