State-space model of grid-connected inverters under current control mode

Abstract

The growth of distributed generation has led to distribution systems with a mixture of rotating machine generators and inverter interfaced generators. The stability of such networks needs to be studied through analysis of state-space models and so suitable models of inverters are needed to complement the well established models of rotating machines. Just as machine models include features such as automatic voltage regulators and wash-out functions so too should the inverter model include phase-locking functions and internal control loops.This paper develops the model for voltage source inverters with an internal current control loop, an outer power regulation loop, a measurement of average power and a phase-locked loop. The model is presented in detail and is formed with a state-vector similar to that used for rotating machines. The model includes non-linear terms but can be linearised about an operating point. The state-space model is verified against a component-level time-step simulation in Simulink/PLECS.

Modeling and simulation of grid-connected photovoltaic distributed generation system

“…Multiple control blocks of the PV system rely on this information to regulate their output command signals. As stated earlier, the PLL computes the rotation frequency of the grid voltage vector by first transforming it to the dq frame, and then force the quadrature component of the voltage to zero to eliminate cross coupling in the active and reactive power terms [12]. A proportional-integral controller is used to perform this task.…”

Bibliometric Analysis of Distributed Generation

“…The addition of DG on the distribution system transforms the distribution system into a multi-source system. Topics such as distribution system protection, control and stability, which were not considered when designing distribution systems, have now become of major importance [15], [16], [17]. The planning and reliability of the distribution system will be affected with the addition of DG sources [18], [19], [20], [21].…”

Dynamic Modeling and Analysis of Single-Stage Boost Inverters under Normal and Abnormal Conditions

“…extensively used in literature for investigation of the dynamic performance of large power systems in the presence of the grid-connected inverters [59][60][61][62][63].…”

“…, then it is possible to apply the theorem of periodic averaging (see Appendix A), and approximate the system model with a set of timeinvariant differential equations. In this study, ideal switches operating at a high switching frequency are assumed for the SSBI in order to apply the aforementioned theorem [49,57,59]. As the first step, averaging technique is applied to the state-space equations of the stand-alone SSBI system in Sector (I).…”

“…assumed that the switching operation is ideal and the switches are lossless and operated at sufficiently high frequency so that the switching action itself does not affect the evolution of the states. As a result, the SSBI operates in continuous mode and the state-space averaging can be applied [49,57,59]. …”