초록 ▼

In an electric vehicle, the traction motor is driven from a battery by way of a controllable electric power switcher. In operation of the switcher, the power losses of the switches depends upon the power being handled; during acceleration the power is high, and at constant speed on level ground the

In an electric vehicle, the traction motor is driven from a battery by way of a controllable electric power switcher. In operation of the switcher, the power losses of the switches depends upon the power being handled; during acceleration the power is high, and at constant speed on level ground the power is small. Thus, the power "dissipated" by the switches varies with time. A cooler transfers heat from the switcher. During acceleration, the cooler may not be sufficient to limit the instantaneous switch temperature. A phase-change heat "sink" coupled to the switches absorbs heat from the switches during hard acceleration, and returns the heat to the cooler under more constant-speed conditions.

대표청구항 ▼

1. A vehicle includingan electric traction drive machine; a source of electrical energy; a controllable switching arrangement coupled to said traction drive machine and to said source of electrical energy, for coupling energy between said source of electrical energy and said motor under the control

1. A vehicle includingan electric traction drive machine; a source of electrical energy; a controllable switching arrangement coupled to said traction drive machine and to said source of electrical energy, for coupling energy between said source of electrical energy and said motor under the control of control signals; operator-controlled control means coupled to said switching arrangement, for controlling the amount of energy coupled between said source and said machine by synthesizing a current waveform; a cooling system coupled to said controllable switching arrangement, for transferring heat from said switching arrangement to ambient; and a phase change energy transducer coupled to said cooling system and to said switching arrangement, for transiently absorbing heat generated by said switching arrangement in excess of that which said cooling system can instantaneously transfer.