Building the smart grid wide-area monitoring system

Abstract

The growing concerns with global warming prompted many governments to mandate increased proportion of electricity generation from renewable sources. This, together with the desire to have more efficient and secure power generation and distribution, has driven research in the next-generation power grid, namely, the smart grid.

Phasor measurement units (PMU) are measuring devices that offer accurate and time-synchronized phasor data to the control center. They can significantly improve the performances of power system monitoring and control and, therefore, are considered the fundamental components in the smart grid. However, since they are expensive devices and generate excessive amount of data traffic, two major questions have to be properly addressed before they can be fully utilized: How do we install PMUs in an economical manner to achieve full system observability? And how do we build up the communication system that can support this number of PMUs in the system?

In this dissertation, we first propose a three-entity smart grid communication framework that focuses on the communication systems enabling smart grid. This communication framework lays the foundation for the rest of the thesis. We start by solving the PMU placement in very large power systems using a meta-heuristic algorithm called simplified chemical reaction optimization (SCRO). After that, we propose the optimal multistage PMU placement (OMPP) problem to address the economic issues brought about by massive scale PMU installations and solve it using SCRO. Then we investigate techniques to alleviate the short-term data communication burdens by optimally installing phasor data compression units (PDCU) to reduce overall system bandwidth requirements. We make this optimal PDCU installation (OPI) problem readily solvable by commercial software by formulating it under the integer linear programming (ILP) framework. Last but not least, we formulate the optimal PMU-communication link placement (OPLP) problem that gives an answer to the question: if one wants to build aWAMS for smart grid, what is the most economic way to do so considering both the costs of PMU placement and the installation costs of a communication network that supports these PMUs? The OPLP problem is formulated under the integer quadratic programming (IQP) framework.