| 摘要 |
PURPOSE: To prevent shock when switching from a low-speed mode to a high- speed mode in an electric vehicle with a battery as a power supply. CONSTITUTION: A motor 4 with a brush 11 for low speed and a brush 13 for high speed at a negative electrode side is used, a voltage applied to the brush 11 for low speed is gradually reduced by a controller 1, and at the same time a voltage applied to a brush 13 for high speed is gradually increased, thus preventing shock on switching, achieving a smooth running from low to high speeds, and at the same time preventing transistors 8 and 9 for conduction for low and high speeds from simultaneously being subjected to high-load conduction, and hence improving the durability of the transistors 8 and 9. |
