Towards efficient real-time deviation settlement mechanism for the Indian grid

In the present Indian scenario, the real-time deviations are settled based on a deviation charge linked to average block frequency. This charge remains uniform across the country irrespective of the occurrence of congestion. Thus, it does not include the locational effect, which may devoid better investment signals and efficient system operation. Therefore, this study proposes an efficient real-time deviation settlement mechanism for the Indian grid, which incorporates the locational signal in the deviation charges. The proposed method introduces a new network adjustment charge (NAC) for each state, which is determined a priori using the nodal prices obtained from an optimal power flow model and using deviation elasticity of the states. This NAC will be added to the existing deviation charge, in each time block for the real-time deviations of the entities and discourage them from deviating in the occurrence of congestion. This method will help in bringing convergence between the deviation charges and another parallel trading mechanism facilitated by power exchanges. The proposed methodology is implemented and validated on a practical data of southern regional grid of India.