Transient Stability Assessment of Hybrid Distributed Generation and its Impact on Critical Clearing Time and Oscillation Duration Considering its Complementary Nature

Presently, the grid accommodates several mixed energies so as to improve power generation and cater for demand which is ever increasing. These energy sources interact with each other and with the existing grid. Due to the complementary nature of most renewable energy and the mixed dynamics associated with them coupled with the bi directional power flow, transient stability based on single source will not give the overall assessment of the network. This paper presents the impact of hybrid Solar PV-Wind and Small Hydro distributed generation on transient stability of power system so as to take advantages of their complementary roles. To investigate this impact, a detail modeling of grid connected wind / solar PV and small hydropower system with single machine infinite system is carried out. The configuration of the proposed typical grid connected hybrid distributed generation (HDG) consists of hybrid Doubly fed induction generator (DFIG), solar PV and small hydropower system. DFIG is integrated through PWM converter into the existing grid while the solar PV consisting of DC sources is integrated through PWM inverter and the hydro power is directly connected through a synchronous generator. The simulation was done in DIgSILENT power factory software