摘要 |
While, from time (t3) when a battery state-of-charge (SOC) has become less than or equal to a setting value (SOCs), the duration time of this state (SOC < SOCs) is being measured, regeneration limit torque (Tm_Lim) is gradually decreased to zero until a running-out-of-electricity determination time (t6) when a predetermined time (”TMs) elapses and regenerative braking torque (Tm) is restricted so as not to exceed the regeneration limit torque (Tm_Lim) during the period from the time (t3) to the time (t6), thereby gradually reducing the regenerative braking torque (Tm) to zero. By gradually reducing the regenerative braking torque (Tm) to zero during the period from the time (t3) to the time (t6), the regenerative braking torque (Tm) does not abruptly disappear at the moment of time (t6) when a battery is brought into the state of running out of electricity, so that it is possible to avoid a speed decreasing change causing a sense of discomfort due to the abrupt disappearance of the regenerative braking torque (Tm). The amount of the gradual decreasing of the regenerative braking torque (Tm) is covered by frictional braking torque (Tb), thereby keeping the combined braking torque (Tm + Tb) cons |