Analysis of the damping characteristics of two power electronics-based devices using ‘individual channel analysis and design’

Abstract

a b s t r a c tA comparison of the capabilities of two quite distinct power electronics-based 'flexible AC transmission systems' devices is presented. In particular, the damping of low frequency electromechanical oscillations is investigated aiming at improving the performance of power systems. The comparison is made using frequency domain methods under the 'individual channel analysis and design' framework. A synchronous generator feeding into a system with large inertia is used for such a purpose. Two system configurations including compensation are analysed: (a) in series in the form of a thyristor-controlled series compensator, and (b) in shunt through a static VAr compensator featuring a damping controller. Analyses are carried out to elucidate the dynamic behaviour of the synchronous generator in the presence of the power electronics-based controllers and for the case when no controller is present. Performance and robustness assessments are given particular emphasis. The crux of the matter is the comparison between the abilities of the static VAr compensator and the thyristor-controlled series compensator to eliminate the problematic switch-back characteristic intrinsic to synchronous generator operation by using the physical insight afforded by 'individual channel analysis and design'.

Individual Channel Design-Based Precise Analysis and Design for Three-Phase Grid-Tied Inverter With LCL-Filter Under Unbalanced Grid Impedance

“…To address the aforementioned issues, this paper proposes a precise analysis and design method based on ICAD for threephase grid-tied inverter under the unbalanced grid impedance. The ICAD is a frequency domain-oriented framework [30], [31], which can be utilized to investigate the potential and limitations for feedback design of MIMO system, formulate a preferable analytical structure and provide a solution methodology for the stability evaluation [32]- [34]. More details could be found in [30]- [35], which fall beyond the scope of this paper.…”

“…In ( 14), γ(s) is called the multivariable structure function (MSF) [32], whose magnitude quantifies the cross-coupling between channels α and β. γ(s) inherently reveals important natures on the structural robustness. The structural robustness can be guaranteed if γ(s) complies the following constrain conditions: (b.1) γ(s) has no right-hand plane poles.…”

Impedance-Based Stability Analysis of Grid-Connected Inverters under the Unbalanced Grid Condition

“…There have been many studies on the influence of the unbalanced grid impedance on the stability of grid-connected inverters [29][30][31][32][33][34][35]. The multi-input multi-output (MIMO) impedance model has been established for inverters under the unbalanced grid condition.…”

Analysis of the contribution of wind power plants to damp power system oscillations

“…The main advantages and drawbacks of each alternative are examined. Frequency domain tools such as the RGA and the multivariable structure function (MSF) [164,165,166] are employed to assess the interaction between signal pairs. Using the frequency domain approach, the arising control design and performance limitations under the presence of right hand plane zeros (RHPZs) are clearly defined [167].…”