| 摘要 |
<p>The invention relates to an electric power installation for voltage adjustmen, applied to the DC traction motors of the 25 kV/50 Hz electric engines. The electric power installation for voltage adjustment of traction motors claimed by the invention has the traction transformer (1) supplied directly from the contact line. The voltages supplied by the traction secondary windings (1.1 ... 1.6) are rectified by high power factor rectifier PFC (3.1 ... 3.6) and then lowered in value by choppers (4.1 ... 4.6) and applied to the rotors (9.1 ... 9.6) of the traction motors (8.1 ... 8.6). Both in the traction and in the rheostatic braking conditions the excitations (10.1 ... 10.6) are supplied by the controlled rectifier (11) having also the role of a running switch, connected to the braking transformer (2). In rheostatic braking conditions, the rotors are connected to the braking resistors (5.1 ... 5.6) by two contactors (6.1 ... 6.6 and 7.1 ...7.6) allowing the operation of the motors in traction conditions, in case of ground-connecting to the braking resistors. The independent excitation operation allows the traction at the limit of adhesion, by adjusting the rotor voltages even in the case of isolating more rotors, including in weakened field conditions. By eliminating the dimmer, reducing the number of contactors and simplifying the power wiring, the reliability is increased and the maintenance operations are reduced.</p> |
