HV ECU (a component with only one name, hooray!)
The HV ECU is the primary power plant ECU. It tells the engine (ICE) when to run, when to stop, and how much power to produce. It tells the ABS ECU how to brake. It directs the charge and discharge of the HV battery after consulting with the HV Battery ECU. Perhaps most importantly, it drives the MGs (Motor/ Generators) by controlling the inverter.