The design of wind plant reactive compensation system alternatives to meet grid code requirements

The paper will investigate cost effective equipment application alternatives that supply reactive compensation support for wind plants to meet the increasing demands of grid codes. Four main approaches will be investigated:- i) A hybrid system solution, which is a combination of DSTATCOM® inverter based compensation and switched shunt devices (SSDs) such as switched capacitor or reactor banks. This application assumes the WTGs operate at a fixed power factor ii) An integrated (or cooperative) hybrid system solution, using a DSTATCOM® inverter based compensation and reactive power capabilities of the wind turbine generators, iii) An all inverter DSTATCOM® solution with the WTGs operating at fixed power factor, iv) A fully integrated approach of a DSTATCOM® inverter based system combined with reactive power capabilities of the wind turbine generators. This system will also use a bias capacitor bank that is permanently connected to the system (i.e. no switching intended to meet reactive requirements) The paper will show the reactive capability of the various alternatives and compare them specifically to the relevant grid code. It will also illustrate how recent developments have enabled all of the above approaches to be used to meet the continuous operation requirements of the grid code. The paper will present both the results of simulation as well as results from field measurements during compliance testing. It will also present an overview of specific projects and how they were configured to meet grid code requirements.