What are the specific grid code requirements related to fault ride-through for wave energy installations?

Fault ride-through (FRT) requirements in grid codes dictate how a power generation facility, such as a wave energy installation, must behave during grid faults, like voltage dips caused by short circuits. The specific FRT requirements vary depending on the grid code of the country or region, but generally, they mandate that the wave energy installation must remain connected to the grid and continue to operate, or at least provide reactive power support, during and after a fault. This is crucial for maintaining grid stability. Typically, grid codes specify a voltage-time profile that the wave energy installation must withstand. For example, the installation might be required to remain connected during a voltage dip of 80% for a certain duration (e.g., 150 milliseconds) and then gradually ramp up its power output as the voltage recovers. The wave energy installation must also be capable of providing reactive power support during the fault to help restore the voltage. This often involves injecting reactive current into the grid to compensate for the voltage drop. Failure to meet these FRT requirements can result in penalties or even disconnection from the grid. Therefore, careful design and control of the power electronics and control systems are essential to ensure that the wave energy installation can ride through grid faults and contribute to grid stability.