Constant-Power Hydraulic Drive and Dynamic Volume-Compensated Leakage Detection for a Grain Silo Sweep Auger

A constant-power hydraulic drive and a leakage-detection method based on dynamic volume compensation are developed for a grain silo sweep auger to address insufficient torque under low-speed heavy-load conditions and false flow-balance alarms caused by rapid pressure variations. A variable-displacement axial piston pump and a load-sensing circuit provide adaptive pressure-flow regulation. A flow residual is established from the supply, return, and motor case-drain flow rates, and dynamic volume compensation attenuates the effects of fluid compressibility, line elasticity, and accumulator charging and discharging. Within the constant-power envelope, the drive extends the low-speed heavy-load operating range by trading rotational speed for torque. The compensated residual suppresses transient flow disturbances during load variations while retaining the imbalance caused by sustained external leakage. At 45 kW, the predicted torque reaches 6900 N·m at approximately 62.3 r/min, or 2.10 times the rated torque of the original electric drive. Leakage decisions additionally require residual persistence and agreement with reservoir-level trends to separate hydraulic faults from sensor failures.