The second device is an insulated-gate bipolar transistor (IGBT) a three-terminal power semiconductor device primarily forming an electronic switch. There seems to be a good deal of heat damage in that area, so unless you feel competent tracing circuits, can solder WELL, have experience working with SMT (surface-mounted components), and can use a meter, I'd leave it to a professional. This device has a great deal of current running through it and a hack repair could cause a lot of trouble...like electrocution or a fire. You could replace the board, but the replacement could run you the price of a new unit. What caused the fuse to blow? What were you doing at the time? Fuses blow when there's a short, or the circuit draws more current than it should, which could be for a number of reasons. Did the damage occur before or after the fuse was replaced. Did the unit overheat? There could be more damage than is apparent. Seriously, I know it's tempting to want to tinker, but this isn't the type of device to screw around with unless you have a lot of experience troubleshooting and repairing high-current equipment.