A PID Controller Gain Adjustment Mechanism to Balance EHA Tracking and Health

Abstract

Electro-hydraulic systems power much of today’s working machinery, which often operate in remote or harsh locations where maintenance is difficult. Given the cost and safety concerns of unplanned outages, strategies that prevent breakdowns between service intervals are crucial. One prominent approach is to adjust the parameters of existing controllers in a health-aware manner to potentially extend the remaining useful life (RUL) of the components.Consequently, this paper presents a health-aware adjustment method for a PID-controlled electro-hydrostatic actuator that tunes the controller gain online to balance tracking and health. The method estimates a hidden degradation state using an extended Kalman filter and models the short-horizon degradation as a Wiener process. It derives an inverse-Gaussian RUL distribution from the degradation estimates and fits a ridge model that links control effort to degradation rate. Moreover, a supervisory cost function weighs an integral-squared error against a soft health constraint and selects gain updates accordingly.In accelerated simulation studies, an update of the controller gain slowed degradation and thus extended the RUL. The system met a 95 percent survival target while keeping the control error modest. This approach adds improved life-extension potential with minimal architectural change, and it can run as a cloud-based supervisory layer that updates parameters using recorded data.