Small Signal Stability of a Balanced Three-Phase AC Microgrid Using Harmonic Linearization: Parametric-Based Analysis

Abstract

The growth of power-electronic-based components is inescapable in future distribution grids (DGs). The introduction of these non-linear components poses many challenges, not only in terms of power quality, but also in terms of stability. These challenges become more acute when active loads are behaving as generators and power is flowing in reverse direction. The frequency-domain-based impedance modeling methods are preferred for small signal stability analysis (SSSA) of DGs involving such non-linear components. The harmonic linearization method can be used for impedance estimation, and afterwards, the Nyquist stability criterion can be used for stability analysis. In this paper, a parametric-based stability analysis of grid-connected active loads at the point of common coupling (PCC) is done by changing the parallel clustering distance and size of active loads. The results verify a positive impact on the stability of increasing parallel clustering and distance from the PCC and a negative impact of increasing the size of individual active loads.

Applications of Power Electronics

“…In all of these articles, innovative control strategies have been proposed for AC, DC and hybrid AC-DC microgrids. In [52], a harmonic linearization technique has been deployed to analyze the stability of the AC microgrid in the sequence domain. Focusing more on the higher-level control, an innovative switching control strategy has been developed for EV charging stations to minimize their effect on the performance of a hybrid microgrid system in [53].…”

Small-Signal Stability Criteria in AC Distribution Systems—A Review

“…The one discussed here is transformation into dq reference frame. The other method is harmonic linearization [22,36,37]. NSC and Bode plots are the main stability criteria for SSSA in frequency domain as given in Figure 3.…”

“…The NSC or Bode stability criterion is applied after developing an impedance-based model. Studies on harmonic linearization are presented in [37][38][39][40][41][42][43]. There are various research articles in which this method is used to develop impedance-based models of various converters [44][45][46][47][48].…”

Towards maximising the integration of renewable energy hybrid distributed generations for small signal stability enhancement: A review

“…These have made it difficult to integrate intermittent renewable energy hybrid DG systems into power distribution systems . Meanwhile, different locations of integration and sizes of REHDG units in the DNS affect the system oscillation modes by either improving or depriving the small signal stability of the network . The aforementioned issues make the formulation of REHDGs' optimal allocation problems tasking to solve using simple mathematical models.…”

“…19,20 Meanwhile, different locations of integration and sizes of REHDG units in the DNS affect the system oscillation modes by either improving or depriving the small signal stability of the network. 4,15,[25][26][27][28][29][30][31][32] The aforementioned issues make the formulation of REHDGs' optimal allocation problems tasking to solve using simple mathematical models. To obtain a realistic model, it is very important to represent the network as a dynamic model, use multiple periods for the planning horizon, and include all the pivotal constraints.…”