Application of PSCAD in wind power and wind generator dynamics

Application of PSCAD in wind power and wind generator dynamics

Electranix by Dennis Woodford

As a renewable resource, wind power generation is favored by people for the following reasons. First, as green power, the cost is relatively low; second, it can be put into use quickly. So it ’s no surprise that investors are optimistic about large wind farms with hundreds of megawatts of rated power and investigating the ability to generate thousands of megawatts of wind power.

When considering the construction of a large-scale wind farm, its geographic location must be considered to ensure that a large amount of power can be generated under the normal wind speed in the area to meet the return on investment. However, these farms generally do not require large amounts of energy. Near the load center. Therefore, it is not possible to transmit the full load power emitted by the wind farm.

The first step of the research is to show that the wind farm power can be fully transmitted to the large power grid in an environment with sufficient parallel capacitance compensation. Not only that, under dynamic conditions of failure, the AC transmission voltage must be kept within an acceptable range. If it does not work, a solution must be found, either through additional transmissions or FACTS solutions.

The initial dynamic performance indicators can be evaluated with a stability study. If the research proves that there is a problem, then more detailed analysis is needed to find a best solution for dynamic voltage control. Details that must be included in the simulation:

1. The characteristics of wind turbines, especially its speed control and protection system.

2. Various generators, such as induction or synchronous generators, include applicable power electronics products, such as dual-winding induction motors.

3. AC voltage control strategy

This study must demonstrate that the AC voltage is kept within an appropriate range and that the transient overvoltage is properly coordinated to protect the equipment. If this research is to be applied in actual engineering, it is necessary to continue to conduct in-depth research in the following aspects:

1. Wind turbine and generator type

2. Additional transmission facilities are required

3. Power electronics solutions (FACTS or DC transmission)

4. Impact of wind turbine protection

5. Control strategy and control

When dynamic voltage control and wind farm performance become important, modern electromagnetic simulation tools become crucial. Danish energy company ELTRA, which is building an offshore wind farm of 160,000 watts (or 160MW), chose to use PSCAD as a simulation tool.

What is interesting is the performance of the new wind turbine with a dual-winding induction generator and how it operates dynamically in its inherent system settings. Turbine and generator models with power electronic control systems and protection systems have been built and integrated as examples into PSCAD installation files. Studies have been conducted to confirm the insulation coordination of submarine cables and coordinate their protection strategies, such as induction generators to prevent self-excitation. Furthermore, the simulation mode has become the basis for creating and testing equivalent modes and can be included in a stable program.

The Laeso Syd wind farm in northern Denmark, which is to be built, is undergoing modeling studies to determine whether the power transmitted from the electric field to the ELTRA backbone is AC or DC.