The 60 kW 3-phase interleaved LLC DC-DC converter doubles power output, optimizing operations in demanding applications like EV charging.
LLC DC-DC converters are key components in electronic systems. These converters use resonant techniques to minimize energy loss during power conversion, improving efficiency and reducing heat generation. With features like handling wide input voltage ranges, adjusting the output voltage, and reducing electromagnetic interference, LLC converters are suitable for environments from consumer electronics to industrial and automotive systems. The 60 kW 3-phase interleaved LLC DC-DC converter reference design from Wolfspeed, CRD-60DD12N-K, advances beyond the previous 30 kW model, doubling its power output for applications that demand high power density and efficiency.
Applications of the design include EV fast charging stations, high-voltage direct current (HVDC) systems, enterprise servers and telecommunications infrastructure, and industrial power supplies. The design incorporates 1200 V C3M Silicon Carbide MOSFETs and 650 V C6D Silicon Carbide Schottky diodes, optimizing it for operation. The converter uses a 3-phase interleaved LLC topology, which minimizes input current ripple and maximizes efficiency, making it suitable for high-power EV charging stations. Using two discrete power devices, the converter reaches power levels traditionally achieved only with larger power modules, providing an efficient, compact solution.
To support various levels of EV charging, the converter offers an output voltage range from 200 V to 1000 V, achieving a power density of 4.83 kW/L and maintaining more than 98.5% peak efficiency. Its adaptive control system operates within a switching frequency range of 120 to 250 kHz, ensuring optimal performance under all conditions. Additionally, the input voltage is managed between 650V and 900V through an active-front-end AC-DC converter, and the secondary side can be manually configured for series or parallel operation depending on the output voltage required.
The design achieves peak efficiencies over 98.5% and maintains a power density of 4.83 kW/L. This reference design is a package that can be used as a starting point for new Silicon Carbide (SiC) based designs, facilitating integration into existing systems and providing a framework for power technology development.
The design allows both parallel and series output settings for configurations. In a parallel output configuration, it can deliver an output voltage ranging from 200 V to 250 V DC at a maximum of 133 A and from 250 V to 500 V DC at a maximum of 200 A, capped at 60 kW. In a series output configuration, the converter provides an output voltage from 500 V to 1000 V DC at a maximum of 100 A, also capped at 60 kW.
The converter operates at a switching frequency between 120 and 250 kHz and uses forced air cooling for temperature management. It also features a CAN interface that allows monitoring and control through a PC-based graphical user interface, enabling precise control over its operations.
Wolfspeed has tested this reference design. It comes with a bill of materials (BOM), schematics, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
