Location and Identification Method for Low Frequency Oscillation Source Considering Control Devices of Generator

Negative damping oscillation and forced power oscillation are two typical kinds of low frequency oscillation (LFO). The control devices of the generator including the governor and the exciter are the main source of oscillation, which have essential differences to cause LFO. Thus locating and identifying the source of LFO correctly is of great importance to the adoption of reasonable suppression methods and improvement of system stability. This paper presents a method to locate and identify the LFO sources based on the contribution of the generator control devices to the system damping and the phase shift characteristics of the forced disturbance source. Firstly, based on the study of the generator control devices, the general rules of the electric parameters response of two kinds of oscillation are extracted. Then the criteria of LFO source location and identification is presented. And according to the principle of the location and identification criteria, the calculation method of the criterion index based on empirical mode decomposition EMD algorithm is proposed. Finally, the oscillation source location and identification method flow is made to realize the location and analysis of the oscillation sources. The feasibility and effectiveness of the proposed method are verified by practical examples.