Batteries reduce power grid disruptions

Researchers from North Carolina State University and Johns Hopkins University have found that an increase in the use of wind power generation can make the power grid more fragile and susceptible to disruptions.

Typically, the power flowing through the transmission lines of a power grid suffers from small “oscillations,” or deviations from the norm, after a disturbance. Generally, these oscillations are mitigated by means of controllers inside the power generators.

However, if the controls are not strong enough, the oscillations may be “sustained,” reducing the efficiency of power transfer and posing a threat to the stability of the grid.

The researchers found that, under certain circumstances, wind power generators can make these oscillations worse. This is because wind farms produce power erratically.

“To counteract this problem, we have designed a technique that coordinates the activity of controllers inside the wind turbines and battery management systems to even out the flow of power from wind farms into the grid,” says Dr Aranya Chakrabortty, an assistant professor of electrical engineering at NC State.

Specifically, the team developed several algorithms that match control efforts between wind farms and energy storage facilities. If the power output for the wind farm increases, the surplus can be siphoned off to charge batteries at the storage facility, instead of being dumped directly onto the power grid.