Abstract
The electric vehicle fast-charging station is an important guarantee for the popularity of electric vehicle. As the fast-charging piles are voltage source converters, stability issues will occur in the grid-connected fast-charging station. Since the dynamic input admittance of the fast-charging pile and the dynamic output impedance play an important role in the interaction system stability, the station and grid interaction system is regarded as load-side and source-side sub-systems to build the dynamic impedance model. The dynamic input admittance in matrix form is derived from the fast-charging pile current control loop considering the influence of the LC filter. Similarly, the dynamic output impedance can be obtained similarly by considering the regional power grid capacity, transformer capacity, and feed line length. On this basis, a modified forbidden region-based stability criterion is used for the fast-charging station stability analysis. The frequency-domain case studies and time-domain simulations are presented next to show the influence of factors from both the power grid side and fast-charging pile side. The simulation results validated the effectiveness of the dq frame impedance model and the stability analysis method.
Highlights
In recent years air pollution and haze have caused health issues around all the world
This paper develops the dynamic impedance model of the electric vehicles (EVs) fast-charging system in the dq frame at the point of common coupling, and stability of the fast-charging station is analyzed by using the novel forbidden region-based criterion
Stability Analysis Method for the multi-input multi-output (MIMO) System. Since both the input admittance matrix of the fast-charging pile and the output impedance matrix of the AC grid-side in the dq frame are derived in the previous section, the stability can be analyzed by using proper criteria
Summary
In recent years air pollution and haze have caused health issues around all the world. Compared with the traditional LFO, the mechanism of interaction among VSCs and the AC grid is more complex and has not been fully understood These kinds of power electronic interfaced oscillation and instability issues are generally analyzed from the viewpoint of small disturbances by the method of eigenvalues based on the state space model [14] and the impedance method based on frequency theory [15,16,17]. The input admittance of the fast-charging pile is derived from the current control loop by using the frame transformation, and the dynamic model of the grid side is obtained through the output impedance of the grid system, including the power source, transformer, and distribution line, is presented.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
