Optimal SCADA measurement placement in a practical distribution network considering measurement redundancy

An observable power system is an important requirement for developing various applications such as power system operations and controls. In practice, supervisory control and data acquisition (SCADA) measurements providing voltage/current magnitude, active power and reactive power are economically more attractive than measurements in the form of phasor measurement units (PMUs). In addition, careful consideration of measurement redundancy is necessary due to possible failure of SCADA measurements. Therefore, it is valuable to determine the minimum number of SCADA measurements to ensure power system observability even during failure of measurements. Firstly, numerical equations corresponding to available SCADA measurements and the Kirchhoff's current laws from the system topology are derived through AC power flow analysis. Secondly, the observability conditions even with failure of measurements are provided, and an optimization problem is formulated. Finally, an integer particle swarm optimization (IPSO) algorithm is applied for optimal SCADA placement. Simulation in a practical distribution power system show that, compared to existing measurement installation strategies, the proposed method can reduce the number of SCADA measurements, and at the same time ensure system observability with certain degree of measurement redundancy.