Demand and efficiency of congestion management methods on the distribution grid level

Abstract

An entirely renewable energy system requires significant adaptions of existing electrical networks. Apart from conventional grid reinforcement and expansion, an efficient utilisation of existing grid capacities during operation is becoming more important. Grid operators use congestion management in order to ensure a secure supply of all network participants. In Germany, the curtailment of renewable energy generation units is increasingly being used for this purpose. This is critical with regards to the ambitious national climate targets. The present work thus analyses different approaches for reducing renewable energy curtailment, taking relevant grid security criteria into account. A method for simulating operational congestion management has been developed and applied to synthetic power systems as well as a real distribution grid region in Germany. Different approaches for the reduction of renewable energy curtailment are evaluated. Especially the utilisation of formerly unused grid capacities by using curative actions proves to be an efficient approach for minimising curtailment.