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Rotating machines are widely used in almost all industries as a critical component for process availability. Inadvertent failure of rotating machines causes high repair expenses and loss of revenue. Existing Monitoring and Diagnosis (MD and take control actions. This paper further performs extensive testing of Stator M&D by monitoring the evolution of a stator interturn fault, and also lessons learnt from the site installation of an advanced MPR. Test results are presented from actual field data of a damaged rotating machine as well as a simulated stator-turn fault in a real time environment.

The protection of power system infrastructure in general is a mission-critical application, and when applied in the context of shipboard systems, it faces even more demanding requirements in terms of both application security and availability, as well the harsher environment of shipboard applications. This paper reports on a new generation of protection and control system designed for enhanced security, dependability and availability. The principle is based on distributed I/O devices that transmit data and commands digitally over fiber optics, in place of individual discrete copper wires, to traditionally defined relays.

The paper presents a robust P&C system based on IEC 61850-9-2 process bus for distributed protection, metering and control and reports on a pilot installation for a 345kV transmission line application. In particular the solution: • Targets copper wiring as a major cost, labour and time factor, and replaces copper wiring for protection and control purposes in the switchyard and the control room with connectorized fiber-based communication. • Introduces rugged merging units that solve practical problems such as connectivity in harsh conditions, commissioning, maintenance, and expandability. • Uses merging units designed to interface all process interface measuring and control points at a given switchyard location using a common device conforming to IEC 61850 and working with a standard I/O structure: status inputs, binary output commands, transducers and sensors, and instrument transformers. • Uses an optimized communication framework that mirrors the topology of the primary equipment and recognizes the exact data flow patterns, origins and destinations required to accomplish a practical zone-based approach to protection. • Solves the data synchronization problem without reliance on external clocks, and their associated communication-based or hard-wired distribution. • Solves the data-sharing bottleneck for substations of any size without relying on impractical throughputs, in a simple, robust, scalable and maintainable communication framework. • Increases reliability by a novel concept of redundancy and optimized communication architecture. • Eliminates cyber security concerns by using a non-routed communication scheme. • Eliminates the need for extra software tools for setting up the process bus data. • Preserves all major protection principles successfully practiced for decades: ○ separation of protection zones, ○ determinism, ○ independence of devices, ○ simplicity, ○ ability to augment a single protection zone without the danger of affecting adjacent zones, and other potentially problematic aspects. The work presented in this paper reflects the actual development of a complete system encompassing all major protection application types, now available for purchase under GE Multilin HardFiber brand.

The computational capabilities of numerical relays allow the development of sophisticated overcurrent algorithms. These algorithms ensure dependable and fast operation of short circuit protection even under severe saturation of current transformers. This eliminates the need for impractical engineering of such applications, and increases confidence levels in cases with relatively well-rated CTs that do not experience extreme saturation but are exposed to currents much higher than the conventional 20 times rated.

This paper presented two algorithms for enhanced numerical BF protection. The fast reset algorithm for current-based BF detector is based on differentiating between the rotating pattern of a fault current and the decaying pattern of a subsidence current. The algorithm is simple, yet very fast and robust. It uses few factory constants, but they have well defined meanings and can be easily fine tuned in any particular implementation that follows our approach. The algorithm can be further enhanced by recognizing that when the current vector stops rotating and starts decaying due to subsidence, it actually rotates at a significantly lower rate, but in the opposite direction compared with an alternating current. This reversal of the angular speed can be used to strengthen and speed up the algorithm