Universal traction converter PTU can be used both on new tram cars and rebuilt tram cars with asynchronous motors, including T3 cars (the product of Czech Socialist Republic).
The converter provides for energy-efficient speed control of asynchronous traction motors of tram cars.
Power part of the converters is built upon high-power IGBT transistors. In braking modes energy recovery into overhead contact system is provided if there are energy consumers in it. If energy recovery is not possible due to absence of consumers, the energy is dissipated on braking resistors. Switching from regenerative braking to rheostatic one occurs automatically.
Operation with partial energy recovery is possible too.