CONTROL METHOD AND CONTROL DEVICE FOR HYBRID VEHICLE, AND HYBRID VEHICLE

A series hybrid vehicle is disclosed that comprises a power generation motor generator (1), a power generation internal combustion engine (2), a travel motor generator (4), a battery (5), and an inverter device (6). The internal combustion engine (2) has a variable compression ratio mechanism (12). When the travel motor generator (4) is performing regenerative braking operation, if the charge state (SOC) of the inverter device (6) is at or above a prescribed level (SOC1), an electric actuator (46) of the variable compression ratio mechanism (12) is operated to cause high/low variation of the mechanical compression ratio and consume excess regenerative power.