Bus Participation Factor Analysis for Harmonic Instability in Power Electronics Based Power Systems

Abstract

Compared with the conventional power systems, large-scale power electronics based power systems present a more complex situation, where harmonic instability may be induced by the mutual interactions between the inner control loops of the converters. This paper presents an approach to locate which power converters and buses are more sensitive and have a significant contribution to the harmonic instability. In the approach, a power electronics based system is introduced as a multi-input multi-output (MIMO) dynamic system by means of a dynamic admittance matrix. Bus participation factors (PFs) are calculated by the oscillatory mode sensitivity analysis versus the elements of the MIMO transfer function matrix. The PF analysis detects which power electronic converters or buses have a higher participation in harmonic instability excitation than others or at which buses such instability problems have a higher impact. In order to confirm the effectiveness of the presented approach, time-domain simulation results are provided for a 400-MW wind farm in PSCAD software environment.

Modelling and Stability Analysis of Wind Power Plants Connected to Weak Grids

“…In this configuration, the grid side converter usually controls the dc-link voltage, and the machine side converter controls the active power [26]. If the small oscillations of the dc-link voltage are neglected, the dynamics of the wind turbine around and above the fundamental frequency can be predicted by modelling of the grid side converter [27]. Therefore, the dynamics of the machine side converter can be neglected in this paper.…”

Evaluation of Harmonic Contributions for Multi Harmonic Sources System Based on Mixed Entropy Screening and an Improved Independent Component Analysis Method

“…Harmonic sources in a power system become complex and diverse as more nonlinear customers connected to the power grid [ 1 , 2 ]. For a bus with serious harmonic distortion, evaluating the contribution of each customer is essential to identify the dominant harmonic source and to design the effective scheme for harmonic pollution mitigation [ 3 ].…”

Responsibility Identification for Harmonic Oscillation Issues in the Parallel Grid-Connected Inverters System

“…However, it is also significant to identify the responsibility of each converter if the system is likely to suffer the harmonic stability problem. The state-space-based method can be used to tackle this problem through the participation factor (PF) by using the space-state matrix, while this method is not appropriate in a large-scale power system with a large number of converters connected due to the complex formulation of the state matrices [31]. Hence, a new PF analysis for the system stability based on the nodal admittance matrix is proposed in [31], where the participation of converters in harmonic instability can be detected by the PF analysis.…”

“…The state-space-based method can be used to tackle this problem through the participation factor (PF) by using the space-state matrix, while this method is not appropriate in a large-scale power system with a large number of converters connected due to the complex formulation of the state matrices [31]. Hence, a new PF analysis for the system stability based on the nodal admittance matrix is proposed in [31], where the participation of converters in harmonic instability can be detected by the PF analysis. Different from the time-domain space-state modeling, the integration of the impedance modeling approach and resonance modal analysis (RMA) method can be applied in the power-electronic-based power systems such as the multi-paralleled grid-connected system [32] in the frequency domain.…”