Digital DC drives from Sprint Electric regenerate braking energy



With its recently extended PLX range, Sprint Electric offers the latest in regenerative three phase digital DC drive technology. The DC drives are able to regenerate energy back to the mains supply under braking without the need for expensive, complex intermediate storage, resistive dumping or additional power bridges. PLX DC drives are compact, powerful, flexible and easy to program, and available in current ratings between 12 and 2250 Amps at supply voltages up to 690 VAC. A four-quadrant DC drive uses two thyristor bridges to enable it to motor and brake in both directions of rotation. This allows it to reverse the torque to slow the load very gently or almost instantaneously, regenerating energy at the same time. Unlike an AC drive, it is able to generate full torque at zero speed, enabling the load to be held stationary in complete safety without the need for mechanical brakes, an especially useful feature for winders and hoists. This ability means DC is also ideal for applications such as mixers, extruders and rollers that require high starting torques and accurate control at low or zero speed, as well as for paper machines, wire drawing and machining. Sprint Electric