Liquid-cooled drive

The energy-efficient liquid cooling of the Allen-Bradley PowerFlex 700L drive allows it to be installed in conditions where air-cooled drives simply could not operate. These include dusty environments or those where increases in climate control costs would be excessive. Applications, which can benefit from this technology include HVAC and chillers, pumping applications, oil and gas, and marine propulsion.

The PowerFlex 700L is available in power ranges from 150-860 kW and requires less floor space than conventional air-cooled drives. Unlike other liquid-cooled drives, which require a coolant line to each insulated gate bipolar transistor (IGBT), the PowerFlex 700L features a single cooling input and output to the IGBTs. This proprietary liquid-cooled heatsink greatly increases power density, resulting in a drive that is up to 65% smaller than similarly power-rated air-cooled drives.

The PowerFlex 700L also features regenerative energy capabilities. The use of IGBTs instead of diodes in its AC-to-DC converter section results in the drive’s active rectifier allowing regenerated energy — commonly occurring in high-power applications such as presses and centrifuges — to be safely returned to the facility’s power system, boosting energy efficiency. Regenerative energy is actively modulated to avoid harmonic disturbances, making the drive one of the quietest in the industry.

An active rectifier also provides PowerFlex 700L with the ability to boost and regulate the drive’s DC bus voltage, minimising the effects of input voltage disturbances and power line dips. This technology also provides a power line voltage boost that enables the drive to control a single voltage motor on both 400 and 480 V power lines.