Innovative Approach to Automatically Detect Ground Faults in Shipboard Control System

The DDG-51 class Machinery Control System (MCS) depends on a ground (hull) isolated, or"floating", power and signal reference system to achieve performance requirements and protect sensitive components. Latent manufacturing defects, high vibration operating environments, component failures, or handling and maintenance activity result in ground faults where-in the isolated reference system becomes shorted to the hull ground. Existing manual methods for detecting and localizing ground faults in the DDG-51 class Machinery Control System (MCS) are time consuming and result in significant and unpredictable loss in operational availability. Ground Fault Detection techniques and equipment used in commercial industry are invasive, lack automation, or do not address the sensitive operational nature of the MCS system and would be prone to affecting system performance and therefore do not sufficiently address the problem. In order to reduce costs and improve Ao, an automated ground fault detection system is proposed. This system consists of strategically located common mode current detection probes networked to a processing engine which executes diagnostic algorithms to detect and identify the cable containing the ground fault. Detection and localization is determined by the proportion of current detected in a particular probe relative to that detected in other probes.