A two-stage Markov model–aided frequency-duration technique for reliability analysis of phasor measurement unit microwave communication networks

The necessity for effective real-time monitoring and control, coupled with the developments in the fields of communication and sensor technologies, led to the emergence of the smart grid. The phasor measurement unit has emerged as an important sensor for the smart grid. The phasor measurement unit communication network is another crucial component which transfers the real-time sensor data measured by the phasor measurement unit to the phasor data concentrator for subsequent monitoring and control. Thus, its reliable operation is essential. The key parameters for assessment of reliability are the failure rate and the steady-state availability. This article presents a two-stage Markov model–aided frequency-duration technique for the reliability analysis of the phasor measurement unit microwave communication networks. Microwave communication network is a complex system as it requires several intermediate relaying towers or the microwave repeaters for communication feasibility. The Markov model explores the transition to the different system states and the frequency-duration approach estimates the frequency and duration of each of these states, thereby providing a simple and elegant means to compute the failure rates of a complex system. It provides a generalized expression for evaluating the systems availability and aids in diagnosing the components that are more prone to failure. Subsequently, this approach is used for the optimal placement of the phasor measurement units such that their resultant microwave communication networks are maximally available. Case study results for the Eastern power grid of India are presented to validate the credibility of the proposed approach.