Y. Wu
20 records found
1
Authored
A Variable Switching Frequency Front-End Converter for EV Chargers
Enhancing Efficiency and Minimizing Harmonics
In recent years, significant research and adoption of periodic variable switching frequency PWM (P-VSFPWM) have been observed in AC/DC voltage source converters (VSCs). This technique aims to reduce ripple in AC inductor current and DC capacitor voltage, suppress injected curr ...
High efficiency can be achieved in grid-connected converters by implementing a zero-voltage switching mechanism, such as the integrated triangular current mode (iTCM) modulation, which reduces the switching losses in the semiconductors. The iTCM can be readily adapted to a thr ...
The sinusoidal Triangular-Current-Mode (S-TCM) method has been proposed in the AC/DC power-factor-correction (PFC) converter to achieve the zero-voltage-switching (ZVS) which can lead to both, high efficiency operation and a high power density design. Nevertheless, the necessa ...
Design Guideline for PWM Converter Implementing Periodic VSFPWM
A Comprehensive Analysis on the Harmonics Spectrum
Reinforcement of the legacy grid infrastructure will be very costly and thereby unrealistic. Consequently, weak grid connection of electric vehicle (EV) chargers will sooner or later be the case. It may however bring instability issues since the EV chargers that can work well ...
Variable switching frequency PWM (VSFPWM) modulation can be advantageously implemented in industrial applications, such as renewable energy, motor drives, and uninterrupted power supply (UPS) systems, to reduce the injected current harmonic amplitudes, to suppress audible nois ...
This paper presents the study of a 100kW electric vehicle (EV) fast charger based on a 12-pulse rectifier cascaded with two buck-type DC-DC converters. The proposed circuit operates with a triangular current shaping method which considerably improves the current harmonics perf ...
This paper proposes a solution to the circuit topology of heavy-duty electric vehicle (HDEV) chargers. In light of the original hybrid rectifier, a new unidirectional Input-Parallel-Output-Series (IPOS) three-phase hybrid rectifier is proposed and analyzed. The IPOS topology i ...
A three-phase buck-type rectifier features a step-down ac-dc conversion function, which is considered as a prominent solution for electric vehicle chargers and telecommunication systems integrated to the grid above 380 V line to line. However, traditional solutions for those a ...
DC links with back to back voltage source converters are usually built alongside the existing medium voltage ac distribution grids for infrastructure reinforcement. The distribution network operators need to run multiple of such parallel ac and dc links between two substations ...
There is an increasing focus on integrating flexible dc links for bulk power routing in medium voltage distribution grids. In such applications, the ac-dc Modular Multilevel Converter (MMC) devised for medium voltage and high-power ratings can be an interesting choice. This pa ...