Patent ID: 6838839

Claim:
An electric circuit of an electric vehicle, said circuit comprising: (a) a drive-motor; (b) a drive-motor driving device; (c) an electric compressor for air-conditioning the vehicle; (d) compressor-driving device; (e) a dc power supply, coupled to input terminals of said drive-motor driving device, for powering both of said drive-motor driving device and said compressor-driving device; (f) a smoothing capacitor coupled to the input terminals of said drive-motor driving device, and shared by both of said drive-motor driving device and said compressor-driving device; (g) a radiator shared by both of said drive-motor driving device and said compressor-driving device; and (h) a case for shielding electromagnetic wave, wherein said drive-motor driving device, said compressor-driving device, said radiator, and said smoothing capacitor are disposed in said case, the input terminals and said smoothing capacitor are connected to each other in the case, the connection extending one set of wires outside the case for coupling to said dc power supply, wherein said smoothing capacitor, which is disposed outside said dc power supply, is coupled to respective input terminals of said drive-motor driving device and said compressor-driving device, a location of said compressor-driving device relative to a location of said smoothing capacitor limits a surge voltage generated by current which flows in wires extending from said smoothing capacitor to said compressor-driving device, and said compressor-driving device lowers an output of said compressor-driving device when load of said drive-motor driving device is above a heavily loaded level.