1. Troley current systems in Europe

3. Electric loco traction drive development Resistance control of DC serie traction motors Puls control of DC traction motors Voltage-Frequency control of induction or synchronous motors DC locos AC locos Tap transformers with diod rectifiers Transformers with GTO or IGBT controlled rectifiers Transformers with puls controlled frequency convertors Multi-system locos

4. TRACTION MOTORS DC traction mors DC separately excited traction motors with controlled exciting current Asynchronous motors Synchronous motors AC traction motors 16 2/3 Hz

5. History of equipment development in ŠKODA factories Resistance control of DC serie traction motors Puls control of DC traction motors with (Chopper Convertor) Transformers with GTO or IGBT controlled rectifiers Asynchronous motor with GTO invertors IGBT traction invertors 3kV DC IGBT trakční convertors for multi.system locos

6. DC Loco BoBo 3 kV-Škoda

7. POWER SCHEME

8. Traction Characteristics

9. DC LOKO WITH PULSE CONTROLLED TRACTION MOTORS

10. AC LOKO WITH PULSE CONTROLLED TRACTION MOTORS

11. MULTI-SYSTEM LOCO WITH PULSE CONTROLLED TRACTION MOTORS

12. Power schemes AC loco with pulse controlled DC traction motors Double level loco with pulse controlled DC traction motors E499,1 DC loco with pulse controlled traction motors 499,3

13. Main circuit: Economic voltage control. Separately excited traction motors Exciting circuit DC current convertor for excitinc current. Stepless shuntinhg Loco internal network: 24V, 48V, 110V Advantages: Without losses during accelerating periot. Velocity control. Beter adhesion, Very good for locos with often speeding up. Disadvantages: Disturbance of safegarding cercuits on the rail tracks- Was solved. Allowed frequences of pulse convertor 16 2/3Hz, 33 1/3Hz, 100Hz, 300Hz Big filter for convertor is needed.

14. Main parameters: Bo´Bo´ 3060kW, 120km/hod, 84t Accelerating: 1. Selectable current (for example 1100A till the velocity 22km/hod), 2. Reducing of the anchor current I k till 850A with elevating of excitation current, (commutation), 3. Reducing of excitation current at constant anchor current 850A 4. Reducing of traction current and excitation current tgill 626A/23A 5. Velocity limitation Braking: Excitation polarity reversing. Traction circuit is switched out from the troley. Braking resistance is switched on into motor circuit. Thyristor in terms shortswitches traction motors and swithes them on. The current is flowing into braking resistance and goes down. Excitation convertor is supplied from the voltage drop on braking resistance.

15. Pulse contrlled DC loco 71E E499,3 Driving characteristics When driving under troley 3kV DC

16. Double level pulse controlled loco 71E E499,1 Driving characteristics When driving under troley 25kV 50Hz