Danfoss’ Dextreme Max shown to extend BE machine runtime

Danfoss Scotland, part of Danfoss Power Solutions, has completed testing of the company’s Dextreme Max system.

The new tech is intended to reduce overall energy consumption of machines using battery-electric powertrains.

Testing with a 30-tonne excavator fitted with a battery-electric powertrain saw energy consumption reduced by 35% across a representative duty cycle. This corresponds to a 53% runtime improvement on a single charge.

This improvement was primarily achieved through the use of the DDP1X0D, a ‘digital displacement’ pump/motor with multiple independently-controlled outlets. This delivers an independent actuator supply, eliminating flow-sharing losses and supporting energy recovery from such motions as boom lowering.

Excavator using Danfoss Dextreme hardware (Photo: Danfoss Power Solutions)

The machine used in the test was a Develon DX300LC‑7 crawler excavator. Originally powered by a diesel engine, the excavator was supplied with an electric drivetrain featuring a Danfoss Editron EM-PMI375 permanent magnet synchronous motor, EC-C1200 inverter, an MC050 motor controller and three batteries with 140 kWh storage capacity.

Danfoss engineers replace the excavator’s standard swashplate hydraulic pump with the DDP1X0D pump/motor. This delivered power to the excavator’s four primary actions, boom, arm, bucket and swing, via 10 independent, individually controllable outlets.

The outlets were grouped through a ganging block, a digital distributor capable of reallocating capacity based on the specific action. To support this, a dedicated valve – operating as a hydraulic H-bridge – was developed and applied to the boom function to support independent metering, while also providing anti-cavitation, pressure amplification and energy recovery during overrun functions.

Multiple test actions were carried out over the test, including JCMAS air grading and JCMAS air dig and dump (equivalent to ISO/AWI TS 11152-2).

The Dextreme Max system reduced battery energy use by 49.2% in air grading and 31% in air dig and dump, with negligible impact on cycle time. Assuming a duty cycle of 30% grading and 70% digging, Dextreme Max would reduce battery power consumption by 35% without significantly impacting work rate.

This would result in 53% longer operating hours with the same battery capacity as the baseline machine, or similar runtime as the baseline with two rather than three battery packs.

“The results of this testing highlight the potential of digital hydraulic architectures to overcome the obstacles in heavy-duty machinery electrification,” said Alasdair Robertson, senior director, Digital Displacement, Danfoss Power Solutions.

“Electric excavators offer excellent responsiveness, smooth control, a quiet cab environment and zero-emission operation. With Dextreme Max, they can also deliver the runtime, productivity, and total cost of ownership advantages required for wider adoption, thereby accelerating the decarbonization of heavy-duty machinery.”