External Thyristor Stack Controllers From Sprint Electric

The main advantages of PLXD thyristor stack controllers are that they can be designed into a new installation, or easily retrofitted to an existing thyristor power stack where the control electronics needs updating or requires adding into a field bus topography network. The PLXD can be supplied with all the latest field bus protocols including Profibus, Modbus RTU, Modbus TCP/IP, CanOpen, Devicenet, Ethernet and more. The same unit is used for 2 Quadrant and 4 Quadrant power stacks. 6 Pulse and 12 Pulse can also be accommodated.

Thyristor stack controllers of the PLXD range are used for controlling external 3 phase thyristor stacks for DC motors. They possess all the functionality of Sprint Electric’s known PLX DC drives range. The PLXD provides gate drive pulses for driving user supplied pulse transformers with primary pulse current up to 1.5 Amp. There are terminals to accept an externally generated isolated armature current signal, field signal, thermal heatsink sensor switch, and high voltage armature voltage feedback. The unit also provides a +24 V supply for the gate drive pulse transformers that is short circuit protected.

The following stack configurations can be driven by the PLXD: 6 pulse 2 Quadrant bridge (6 thyristors), or 2 bridges in parallel (12 thyristors), as well as 6 pulse 4 Quadrant regenerative anti-parallel bridge (12 thyristors). Extra stacks can be used in parallel within the gate drive capability. All customer control terminals are the plug-in screw terminal variety. The PLXD can be used with up to 690 V AC on its 3 phase auxiliary supply inputs (EL1/2/3). The external stacks can be of higher voltages if required. The armature voltage inputs can monitor up to +/-1000 V DC. There is an integral motor field bridge with independent single phase AC supply inputs (EF2/3) for controlling fields up to 32 Amps. The internal field bridge supply input voltage rating is 480 V AC. Provision is made for providing an external field feedback signal and controlling an external field with user supplied primary gate pulse transformer drivers.