TIDUEY6 April 2021
The DC-DC sub-system is designed to take 400V normal HV input. After input filter and capacitor, it drives a SiC full bridge, with a inductor between the center point of left lag and main transformer primary. Current transformer of 100:1 ratio is used for primary inductor current sensing for PCMC control. The characteristic of the main transformer can be found in Table 3-6.
Item |
L (1-2) @100kHz/1V (μH) |
L (1-2) @15A (μH) |
L (1-2) DCR (mΩ) |
Dielectric Strength / Hi-pot (Vac): |
---|---|---|---|---|
VI-19152B | 3.1 TYP. | 3.1 TYP. | 2.0 TYP. | 2500 |
The secondary is designed to be current doubler topology, with 4 MOSFET in parallel for each lag to carry the high current on LV output. Output current is measured with a set of parallel shunt resistor. Since the negative output has a long path on the PCB and high current, a high current bus-bar is designed to carry current between the MOSFETs and the output terminal (mounted on back side of the board).