In recent years, the booming development of new energy industries such as photovoltaic storage and electric vehicles (EVs) has led to a sharp increase in the demand for DC-Link capacitors. In short, DC-Link capacitors play a vital role in the circuit. They can absorb high pulse currents at the bus end and smooth the bus voltage, ensuring that IGBT and SiC MOSFET switches are protected from the adverse effects of high pulse currents and transient voltages during operation.
As the bus voltage of new energy vehicles increases from 400V to 800V, the demand for film capacitors has increased significantly. According to data, the installed capacity of electric drive inverters based on DC-Link thin-film capacitors reached 5.1117 million sets in 2022, accounting for 88.7% of the installed capacity of electric control. The drive inverters of many leading electric control companies such as Tesla and Nidec all use DC-Link film capacitors, which account for 82.9% of the installed capacity and have become the mainstream choice in the electric drive market.
Research papers show that in silicon IGBT half-bridge inverters, traditional electrolytic capacitors are usually used in the DC link, but voltage surges will occur due to the high ESR of electrolytic capacitors. Compared with silicon-based IGBT solutions, SiC MOSFETs have a higher switching frequency, so the voltage surge amplitude in the DC link of the half-bridge inverter is higher, which may cause device performance degradation or even damage, and the resonant frequency of electrolytic capacitors is only 4kHz, which is not enough to absorb the current ripple of SiC MOSFET inverters.
Therefore, in DC applications such as electric drive inverters and photovoltaic inverters with higher reliability requirements, film capacitors are usually chosen. Compared with aluminum electrolytic capacitors, their performance advantages are higher voltage resistance, lower ESR, non-polarity, more stable performance, and longer life, thus achieving stronger ripple resistance and more reliable system design.
Systems using thin-film capacitors can take advantage of the high frequency and low loss of SiC MOSFETs and reduce the size and weight of passive components. Wolfspeed research shows that a 10kW silicon-based IGBT inverter requires 22 aluminum electrolytic capacitors, while a 40kW SiC inverter only requires 8 thin-film capacitors, and the PCB area is also greatly reduced.
In response to market demand, YMIN Electronics launched the MDP series of film capacitors, which use advanced technology and high-quality materials to adapt to SiC MOSFET and silicon-based IGBT. The MDP series capacitors feature low ESR, high withstand voltage, low leakage current and high temperature stability.
Advantages of YMIN Electronics’ film capacitor products：
YMIN Electronics’ film capacitor design adopts the low ESR concept to reduce voltage stress and energy loss during switching and improve system energy efficiency. It has a high rated voltage, adapts to high voltage environments, and ensures system stability.
The MDP series capacitors have a capacity range of 1uF-500uF and a voltage range of 500V to 1500V. They have lower leakage current and higher temperature stability. Through high-quality materials and advanced processes, an efficient heat dissipation structure is designed to ensure stable performance at high temperatures, extend service life, and provide reliable support for power electronic systems. At the same time, the MDP series capacitors are compact in size, high in power density, and use innovative thin-film manufacturing processes to improve system integration and efficiency, reduce size and weight, and increase equipment portability and flexibility.
YMIN Electronics DC-Link film capacitor series has a 30% improvement in dv/dt tolerance and a 30% increase in service life, which improves the reliability of SiC/IGBT circuits, brings better cost-effectiveness, and solves the price problem.
Post time: Jan-10-2025