As photovoltaic （PV） capacity in power system increases, the capacity of synchronous generator needs to be reduced relatively. This leads to the lower system inertia and the higher generator reactance, and hence the...As photovoltaic （PV） capacity in power system increases, the capacity of synchronous generator needs to be reduced relatively. This leads to the lower system inertia and the higher generator reactance, and hence the generator transient stability may negatively be affected. In particular, the impact on the transient stability may become more serious when the considerable amounts of PV systems are disconnected simultaneously during voltage sag. In this work, the generator transient stability in the power system with significant PV penetration is assessed by a numerical simulation. In order to assess the impact from various angles, simulation parameters such as levels of PV penetration, variety of power sources （inverter or rotational machine）, and existence of LVRT capability are considered. The simulation is performed by using PSCAD/EMTDC software.展开更多
To simplify the transient stability analysis of a large-scale power system and realize real-time emergency control,a fast transient stability simulation algorithm based on real-time dynamic equivalence is proposed.Gen...To simplify the transient stability analysis of a large-scale power system and realize real-time emergency control,a fast transient stability simulation algorithm based on real-time dynamic equivalence is proposed.Generator models are grouped and aggregated according to a fast numerical integration.A fast calculation method of the admittance matrix is then proposed to calculate the parameters of an equivalent system,and numerical integration is performed using the obtained equivalent system.Then,based on integral sensitivity,a new fast emergency control strategy is proposed for the equivalent system.The final emergency control strategy is obtained by mapping the control strategy for the equivalent system back to the original system.The results of a simulation on an East China Power System that includes 496 generators and 5075 buses show that the suggested algorithm can output an accurate transient stability simulation result and form an effective emergency control strategy.The proposed algorithm is much faster than the existing solutions and has the potential to be used for online pre-decision.展开更多
文摘As photovoltaic （PV） capacity in power system increases, the capacity of synchronous generator needs to be reduced relatively. This leads to the lower system inertia and the higher generator reactance, and hence the generator transient stability may negatively be affected. In particular, the impact on the transient stability may become more serious when the considerable amounts of PV systems are disconnected simultaneously during voltage sag. In this work, the generator transient stability in the power system with significant PV penetration is assessed by a numerical simulation. In order to assess the impact from various angles, simulation parameters such as levels of PV penetration, variety of power sources （inverter or rotational machine）, and existence of LVRT capability are considered. The simulation is performed by using PSCAD/EMTDC software.
文摘To simplify the transient stability analysis of a large-scale power system and realize real-time emergency control,a fast transient stability simulation algorithm based on real-time dynamic equivalence is proposed.Generator models are grouped and aggregated according to a fast numerical integration.A fast calculation method of the admittance matrix is then proposed to calculate the parameters of an equivalent system,and numerical integration is performed using the obtained equivalent system.Then,based on integral sensitivity,a new fast emergency control strategy is proposed for the equivalent system.The final emergency control strategy is obtained by mapping the control strategy for the equivalent system back to the original system.The results of a simulation on an East China Power System that includes 496 generators and 5075 buses show that the suggested algorithm can output an accurate transient stability simulation result and form an effective emergency control strategy.The proposed algorithm is much faster than the existing solutions and has the potential to be used for online pre-decision.
