Have a look at the book, Robust Control in Power Systems by B.Pal

thanks mr Samundra Gurung , do you have idea about power system stabilizer with DFIG ?

You may like to see, for example, DESIGN_OF_POWER_SYSTEM_STABILIZER.pdf to start with.

Sorry, to be precise, use the link, http://ethesis.nitrkl.ac.in/3683/1/DESIGN_OF_POWER_SYSTEM_STABILIZER.pdf

A robust power system stabilizer (RPSS) is a type of controller that is designed to improve the stability of a power system. RPSSs are typically used in conjunction with other control systems, such as governor control and excitation control.

The design of an RPSS typically involves the following steps:

The design of an RPSS is a complex process that requires expertise in power system modeling, control theory, and simulation. However, RPSSs can be an effective way to improve the stability of power systems and prevent outages.

Here are some of the benefits of using a robust power system stabilizer:

• Improved stability: RPSSs can help to improve the stability of power systems by detecting and responding to disturbances. This can help to prevent outages and improve the reliability of the power supply.
• Reduced costs: RPSSs can help to reduce the costs of power outages by preventing them from happening. This can save money for businesses and consumers.
• Improved performance: RPSSs can help to improve the performance of power systems by reducing oscillations and improving transient response. This can lead to improved power quality and increased efficiency.

Small-signal stability is the ability of a power system to maintain its equilibrium after a small disturbance. In a two-area power system, small-signal stability can be affected by a number of factors, including the type of generators, the interconnections between the areas, and the load characteristics.

Two-area power system with DFIG

A doubly fed induction generator (DFIG) is a type of generator that uses both synchronous and asynchronous windings to generate electricity. DFIGs are often used in wind turbines because they can operate at variable speeds, which is necessary for wind power generation.

The use of DFIGs in a two-area power system can improve small-signal stability. This is because DFIGs have a higher damping ratio than synchronous generators. The damping ratio is a measure of how quickly a system returns to equilibrium after a disturbance. A higher damping ratio indicates that the system is more stable.

Two-area power system without DFIG

A two-area power system without DFIGs is more susceptible to small-signal instability. This is because synchronous generators have a lower damping ratio than DFIGs. As a result, synchronous generators are more likely to oscillate after a disturbance, which can lead to instability.

There are a number of ways to improve small-signal stability in a two-area power system without DFIGs. These include:

• Using power system stabilizers (PSSs): PSSs are controllers that can be used to improve the damping of a power system. PSSs typically work by injecting a signal into the generator governor or excitation system. This signal helps to counteract the oscillations that occur after a disturbance.
• Adding interconnections between the areas: Adding interconnections between the areas can help to improve the stability of the system. This is because the interconnections provide a path for power to flow from one area to another. This can help to dampen oscillations and prevent instability.
• Balancing the load: Balancing the load can help to improve the stability of the system. This is because unbalanced loads can create torque imbalances in the generators. These torque imbalances can lead to oscillations and instability.

By taking these steps, it is possible to improve small-signal stability in a two-area power system without DFIGs. This can help to prevent outages and improve the reliability of the power supply.