The ongoing evolution of the power system towards a "SmartGrid" implies dominant role electronic converters, but poses strict requirements on their control strategies to preserve stability and controllability. In this perspective, definition decentralized schemes for converters that can provide grid support allow seamless transition between grid-connected or islanded operation is critical. Since these features already be provided by synchronous generators, concept Virtual Synchronous...

Over the last decade, frequency-droop-based control schemes have become preferred solution in microgrids dominated by power electronic converters. More recently, concept of virtual synchronous machines (VSMs) has emerged as an effective method for adding inertia to system through These two approaches been developed separate contexts, but present strong similarities. In fact, they are equivalent under certain conditions, demonstrated this letter. Analysis equivalence provides additional...

The concept of Virtual Synchronous Machines (VSM) is emerging as an alternative approach for control power electronic converters operating in the system. One main motivation applying VSM-based to achieve a simple emulating inertia effect traditional synchronous machines. This paper provides comprehensive literature review on VSM and possible classification different schemes. In addition, small-signal response emulation characteristics proved be equivalent conventional droop-based standalone...

This paper presents a comparison of the small-signal stability properties for virtual synchronous machines (VSMs) with dynamic and quasi-stationary representation internal machine (SM) model. It is shown that electrical equations may introduce poorly damped oscillations when realistic stator impedance values high-power SMs are used. The implementation less sensitive to model, but depends on filtering measured d- q-axes components ac-side voltage avoid instability or oscillations....

Control structures containing cascaded loops are used in several applications for the stand-alone and parallel operation of three-phase power electronic converters. Potential interactions between these complex functional dependence controller parameters system dynamics prevent effective application classical tuning methods case converters operating with a low switching frequency. A approach guided by eigenvalue parametric sensitivities calculated from linearized model converter its control...

This paper presents a single-phase virtual synchronous machine (VSM) and its possible application for providing vehicle-to-grid (V2G) services from domestic battery chargers of electric vehicles (EVs). In VSM, the power converter is controlled to emulate inertia damping effect machine. Thus, VSM-based EV charger can contribute spinning reserve frequency regulation system. case grid outages, VSM seamlessly establish an islanded supply local loads onboard EV. order avoid influence on...

In this paper, a methodology is presented to identify and analyze interaction modes between converters in voltage-source converter multiterminal high-voltage direct current (VSC MTDC) systems. The absence of substantial level energy stored such power-electronics-based systems results fast system dynamics, governed by electromagnetic phenomena. Moreover, interactions are largely influenced the control parameters and, general, an priori identification based on associated time constants less...

This paper presents an evaluation of two interface design solutions for power hardware-in-the-loop experiments. The is performed according to four figures merit that focus on both the dynamic and steady-state performances systems. An analytical process then used compare different interfaces and, more importantly, define a procedure based optimization problem. primary advantage proposed approach merits can be calculated by accounting not only topology but also structure characteristics...

This paper demonstrates how the range of stable power transfer in weak grids with voltage source converters (VSCs) can be extended by modifying grid synchronisation mechanism a conventional synchronous reference frame phase locked loop (PLL). By introducing an impedance‐conditioning term PLL, VSC control system virtually synchronised to stronger point counteract instability effects caused high impedance. To verify effectiveness proposed approach, maximum static capability and small‐signal...

Virtual Synchronous Machines (VSMs) have been introduced as a control concept for emulating the behavior of traditional synchronous machines with power electronic converters. This paper analyses VSM scheme where an outer loop inertia emulation provides references two cascaded voltage and current controllers. offers several advantages compared to alternative implementations. However, interactions between loops complex functional dependency system dynamics respect controller parameters...

State‐of‐the‐art time‐domain models of power cables account for the frequency dependency physical parameters to enable accurate transient simulations high‐voltage transmission schemes. Owing their formulation, these cannot be directly converted into a state‐space form as required small‐signal eigenvalue analysis. Thus, dc are commonly represented in direct current (HVDC) system stability studies by cascaded pi‐section equivalents that neglect frequency‐dependent effects. This study...

The concept of Virtual Synchronous Machines (VSMs) is emerging as a flexible approach for controlling power electronic converters in grid-connected well stand-alone or microgrid applications. Several VSM implementations have been proposed, with the emulation inertia and damping traditional Machine (SM) their common feature. This paper investigates implementation based on Voltage Source Converter (VSC), where virtual swing equation provides phase orientation cascaded voltage current...

The dc-side dynamics of modular multilevel converters (MMCs) can be prone to poorly damped oscillations or stability problems when the second-harmonic components arm currents are mitigated by a circulating current suppression controller (CCSC). This paper demonstrates that source these is uncontrolled interaction and internally stored energy MMC, as resulting from CCSC. Stable operation improved performance MMC control system ensured introducing closed-loop current. presented analysis relies...

The Virtual Synchronous Machine (VSM) concept is emerging as a flexible approach for controlling power electronic converters in grid-connected well stand-alone or microgrid applications. Several VSM implementations have been proposed, with the emulation of inertia and damping traditional (SM) their common feature. This paper investigates implementation based on Voltage Source Converter (VSC), where virtual swing equation provides phase reference cascaded voltage current control synchronous...

With increasing penetrations of wind generation, based on power‐electronic converters, power systems are transitioning away from well‐understood synchronous generator‐based systems, with growing implications for their stability. Issues concern will vary system size, penetration level, geographical distribution and turbine type, network topology, electricity market structure, unit commitment procedures, other factors. However, variable‐speed turbines, both onshore connected offshore through...

This paper demonstrates that the sum and difference of upper lower arm voltages are suitable variables for deriving a generalized state-space model modular multilevel converter (MMC) which settles at constant equilibrium in steady-state operation. The presented modeling approach separates multiple frequency components appearing within MMC as first step derivation, to avoid containing steady state. On this basis, it is shown Park transformations three different frequencies ( <inline-formula...

This paper presents a comparison of the small-signal stability properties for virtual synchronous machines (VSMs) with dynamic and quasi-stationary representation internal machine (SM) model. It is shown that electrical equations may introduce poorly damped oscillations when realistic stator impedance values high-power SMs are used. The implementation less sensitive to model, but depends on filtering measured d - q -axes components ac-side voltage avoid instability or oscillations....

Small-signal state-space analysis of power system stability relies on linearized models where steady state operation corresponds to constant values all variables. Such are available and commonly used for configurations with three-phase 2- or 3-level Voltage Source Converters (VSC). However, the Modular Multilevel Converter (MMC), which is emerging as a preferred topology VSC-based HVDC transmission, based single-phase modules internal capacitors experiencing double frequency voltage...

The internal currents and voltages of modular multilevel converters (MMCs) contain multiple frequency components in steady-state operation remain time-periodic even when transformed into a synchronously rotating reference frame. This prevents straightforward state-space representation, where constant equilibrium point is reached all state variables converge to values under conditions. Such time-invariant (SSTI) representations are needed for linearization eigenvalue-based analysis...

The increasing diffusion of renewable energy sources in the power systems is likely to extend near future supply railways. This paper compares technical and economic benefits several configurations with electronics converters for integration photovoltaic (PV) into railway systems. For each these configurations, a design methodology proposed selecting ratings components. requirements phase imbalance on feeding transmission line are assumed accordance current regulatory standards and, wherever...

The single-stage grid-connected photovoltaic (PV) topology has recently drawn attention as it can reduce overall losses and installation costs. This paper presents a new control approach for PV systems. proposed controller is combination of finite set model predictive (FCS-MPC) maximum power point tracking (MPPT) algorithm, which ensures the extraction from panels good transient performance output voltage current. disadvantages classical MPPT algorithms in global under fluctuating...