Figure 1 - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
![Integration of power electronic interface distributed generation into the future power system [6,10].](publication/365315522/figure/fig1/AS:11431281096672137@1668197679188/Integration-of-power-electronic-interface-distributed-generation-into-the-future-power.png)
Integration of power electronic interface distributed generation into the future power system [6,10].
Source publication
![Figure 13. Virtual-synchronous generator (VSG) topology [18].](publication/365315522/figure/fig2/AS:11431281096641073@1668197679223/Virtual-synchronous-generator-VSG-topology-18_Q320.jpg)
In recent years, the penetration of renewable power generations into the electrical grid has substantially increased. Continuous deployment of power electronic-based distributed generations and the reduction of traditional synchronous machines with their essential dynamics in modern power networks are very critical in this change. The use of power...
Contexts in source publication
Context 1
... from their intermittency, they are integrated via power conditioning circuits that detach them from the power grid [4,5]. Using power electronic converters, RES and loads are incorporated into the grid in a future power system, as depicted in Figure 1 [6]. Consequently, when conventional generators are changed with renewable energy sources, the effective inertia of the electrical grid is reduced. ...
Context 2
... a power imbalance, this drop leads to a rapid shift in frequency and frequency deviations, which also significantly influences the system's frequency stability [6,9]. Figure 1. Integration of power electronic interface distributed generation into the future power system [6,10]. ...
Context 3
... í µí± and í µí± are the input and output powers (W), í µí°½ is the moment of inertia (Kg·m 2 ), í µí¼ is the virtual angular frequency (rad/s), í µí°· is the damping factor (Kg·m 2 /s), and í µí¼ is the reference value of the angular frequency (rad/s) [18,33]. The input power, í µí± , is calculated using the governor model, as illustrated in Figure 10, where, í µí± is the DG unit's continuous power reference. With gain í µí°¾ and a time constant í µí± , the governor is characterized as a lag element of the first order. ...
Context 4
... SPC, as presented in Figure 11, is another common topology for implementing virtual inertia. The control algorithm's general structure is similar to that presented in the Ise lab's architecture, nonetheless, the converter is not operated as a voltage-or currentcontrolled system; rather, with an inner current and outer voltage control loops, it uses a virtual admittance to build a cascaded control system [34][35][36]. ...
Context 5
... P in and P out are the input and output powers (W), J is the moment of inertia (Kg·m 2 ), ω m is the virtual angular frequency (rad/s), D p is the damping factor (Kg·m 2 /s), and ω g is the reference value of the angular frequency (rad/s) [18,33]. The input power, P in , is calculated using the governor model, as illustrated in Figure 10, where, P 0 is the DG unit's continuous power reference. With gain K and a time constant T d , the governor is characterized as a lag element of the first order. ...
Context 6
... í µí± and í µí± are the input and output powers (W), í µí°½ is the moment of inertia (Kg·m 2 ), í µí¼ is the virtual angular frequency (rad/s), í µí°· is the damping factor (Kg·m 2 /s), and í µí¼ is the reference value of the angular frequency (rad/s) [18,33]. The input power, í µí± , is calculated using the governor model, as illustrated in Figure 10, where, í µí± is the DG unit's continuous power reference. With gain í µí°¾ and a time constant í µí± , the governor is characterized as a lag element of the first order. ...
Context 7
... SPC, as presented in Figure 11, is another common topology for implementing virtual inertia. The control algorithm's general structure is similar to that presented in the Ise lab's architecture, nonetheless, the converter is not operated as a voltage-or currentcontrolled system; rather, with an inner current and outer voltage control loops, it uses a virtual admittance to build a cascaded control system [34][35][36]. ...
Context 8
... SPC, as presented in Figure 11, is another common topology for implementing virtual inertia. The control algorithm's general structure is similar to that presented in the Ise lab's architecture, nonetheless, the converter is not operated as a voltage-or currentcontrolled system; rather, with an inner current and outer voltage control loops, it uses a virtual admittance to build a cascaded control system [34][35][36]. ...
Context 9
... inducverter's active power and frequency can be altered using power electronic inverter-based virtual rotor inertia [6,38]. An inverter with a filter makes up the electrical portion of the inducverter, along with a control portion that makes the inverter behave as an induction machine by generating the voltage signals, as illustrated in Figure 12. This approach offers the benefit of automatic synchronization without a phase-locked loop (PLL). ...
Context 10
... inducverter's active power and frequency can be altered using power electronic inverter-based virtual rotor inertia [6,38]. An inverter with a filter makes up the electrical portion of the inducverter, along with a control portion that makes the inverter behave as an induction machine by generating the voltage signals, as illustrated in Figure 12. This approach offers the benefit of automatic synchronization without a phase-locked loop (PLL). ...
Context 11
... inducverter's active power and frequency can be altered using power electronic inverter-based virtual rotor inertia [6,38]. An inverter with a filter makes up the electrical portion of the inducverter, along with a control portion that makes the inverter behave as an induction machine by generating the voltage signals, as illustrated in Figure 12. This approach offers the benefit of automatic synchronization without a phase-locked loop (PLL). ...
Context 12
... an isolated grid, this functionality is particularly critical, given that the initial ROCOF might be quite large, causing protective relays to be unnecessarily triggered. Figure 13 depicts the structure of the VSG. The system frequency change and ROCOF are measured using a PLL. ...
Context 13
... an isolated grid, this functionality is particula critical, given that the initial ROCOF might be quite large, causing protective relays to unnecessarily triggered. Figure 13 depicts the structure of the VSG. The system frequen change and ROCOF are measured using a PLL. ...
Context 14
... can respond to variations in frequency. The block diagram of the VSYNCH's VSG is presented in Figure 14. In the inertial response, the control method creates a control signal to add, from the storage device, the needed quantity of power. ...
Context 15
... can respond to variations in frequency. The block diagram of the VSYNCH's VSG is presented in Figure 14. In the inertial response, the control method creates a control signal to add, from the storage device, the needed quantity of power. ...
Context 16
... v * represents the reference voltage, v g represents the grid voltage, Q in represents the reference reactive power, Q out represents the DG unit output measured reactive power, and m q represents the reactive power droop. Figure 15 depicts the architecture of the method based on Equation (8). To measure the inverter output power and to attenuate high-frequency parts from the inverter output, a low-pass filter with a time constant T f is frequently employed [18]. ...
Context 17
... has a basic and very simple construction [23], as illustrated in Figure 16, which contains a filter circuit, DG system, storage unit, DC/AC converter, governor, and a grid. If the input torque of the prime mover is considered the power of the DG unit and energy storage device, and it is presumed that the electromechanical energy transfer between the rotor and stator is the DC/AC converter. ...
Context 18
... voltage and current on the AC side of the inverter, displayed in Figure 16, are v abc and i abc , respectively. The filter voltage and current are v oabc and i oabc , respectively. ...
Context 19
... numerous VSG control algorithms have been devised for a power electronic converter to replicate the properties of an SG [23,42,43]. Furthermore, models of VSG can be split according to the need for an additional component, such as energy storage; hence, Figure 17 summarizes the distinctions between VSG models at various phases, as discovered in the literature [42]. ...
Context 20
... has a basic and very simple construction [23], as illustrated in Figure 16, which contains a filter circuit, DG system, storage unit, DC/AC converter, governor, and a grid If the input torque of the prime mover is considered the power of the DG unit and energy storage device, and it is presumed that the electromechanical energy transfer between the rotor and stator is the DC/AC converter. The electromotive force of the VSG is represented by the fundamental component of midpoint voltage. ...
Context 21
... stator winding impedance is represented by the filter's inductance and resistance [23,41]. The voltage and current on the AC side of the inverter, displayed in Figure 16, are í µí±£ and í µí± , respectively. The filter voltage and current are í µí±£ and í µí± , respec tively. ...
Context 22
... numerous VSG control algorithms have been devised for a power electronic converter to replicate the properties of an SG [23,42,43]. Furthermore, models of VSG can be split according to the need for an additiona component, such as energy storage; hence, Figure 17 summarizes the distinctions between VSG models at various phases, as discovered in the literature [42]. ...
Context 23
... second configuration is a current-to-voltage model with energy storage. A shown in Figure 18a, the voltage-to-current model offers set point values of current to manage the VSC, whereas the current-to-voltage model gives reference voltage values, a illustrated in Figure 18b [42,44]. In [44], an evaluation of both VISMA high-order model was conducted during typical operating conditions using distinct switching strategies. ...
Context 24
... second configuration is a current-to-voltage model with energy storage. A shown in Figure 18a, the voltage-to-current model offers set point values of current to manage the VSC, whereas the current-to-voltage model gives reference voltage values, a illustrated in Figure 18b [42,44]. In [44], an evaluation of both VISMA high-order model was conducted during typical operating conditions using distinct switching strategies. ...
Context 25
... second configuration is a current-to-voltage model with energy storage. As shown in Figure 18a, the voltage-to-current model offers set point values of current to manage the VSC, whereas the current-to-voltage model gives reference voltage values, as illustrated in Figure 18b [42,44]. In [44], an evaluation of both VISMA high-order models was conducted during typical operating conditions using distinct switching strategies. ...
Context 26
... second configuration is a current-to-voltage model with energy storage. As shown in Figure 18a, the voltage-to-current model offers set point values of current to manage the VSC, whereas the current-to-voltage model gives reference voltage values, as illustrated in Figure 18b [42,44]. In [44], an evaluation of both VISMA high-order models was conducted during typical operating conditions using distinct switching strategies. ...
Context 27
... [44], an evaluation of both VISMA high-order models was conducted during typical operating conditions using distinct switching strategies. Figure 18b [42,44]. In [44], an evaluation of both VISMA high-order models was conducted during typical operating conditions using distinct switching strategies. ...
Context 28
... features of the high-order VSM model outlined earlier are similar to those of SM. The low-order VSM control technique, on the other hand, is comparable to the traditional droop technique, which is based on the swing equation, as illustrated in Figure 19. The replication of the inertia and damping behavior of SMs may be obtained by employing the swing equation because the major goal behind adding VSM is to emulate SM behavior. ...
Context 29
... features of the high-order VSM model outlined earlier are similar to those of SM. The low-order VSM control technique, on the other hand, is comparable to the traditional droop technique, which is based on the swing equation, as illustrated in Figure 19. The replication of the inertia and damping behavior of SMs may be obtained by employing the swing equation because the major goal behind adding VSM is to emulate SM behavior. ...
Context 31
... general, the voltage control adjusts the output voltage according to the amplitude deviation of the VSG output voltage and utilizes the voltage adjustment coefficient, K q , to characterize the VSG's voltage regulation capabilities. Figure 21 depicts the principal control framework for voltage control and reactive power regulation. In Figure 21, V o and V r represent the actual and reference voltages, respectively. ...
Citations
... 1 Faculty of Graduate Studies, An-Najah National University, Nablus, Palestine 2 Department of Electrical Engineering, Faculty of engineering, An-Najah National University, Nablus, Palestine *Corresponding author: moien.omar@najah.edu Finally, they facilitate a more substantial integration of PV systems onto the grid without compromising its stability (8). ...
This paper presents a control scheme for virtual synchronous generators (VSGs) in PV inverters, designed to enhance grid frequency and voltage. Through the skillful management of active and reactive power, this control scheme enables PV inverters to interact seamlessly with the main grid in response to grid events, including voltage and frequency fluctuations. The VSG controller is implemented using Matlab Simulink, and its effectiveness is rigorously assessed under various scenarios in a case study involves a 50 kVA rated PV inverter, a 50 kW rated PV system, and a 220 V grid phase voltage. In conditions of low power generation from the PV system (solar radiation of 200 W/m²) and high load power (120 kW and 37.5 kVAr), the load voltage drops to 202.4 V. The VSG controller successfully raises the grid voltage by 17.6 V, stabilizing it at 220 V. Conversely, in scenarios of high PV power generation (solar radiation of 1000 W/m²) and low load power (20 kW and 7.5 kVAr), the grid voltage surges by 10 V, reaching 230 V. The proposed control strategy adeptly fine-tunes the voltage, ultimately stabilizing at 220 V. Additionally, when the frequency deviates within ±0.4 Hz from the nominal frequency of 50 Hz, the proposed control effectively restores the frequency to its nominal value.
... The growing implementation of power electronic-based distributed generation systems decreases power system inertia. In the event of a power imbalance, this leads to a significant rise in the frequency rate of change, negatively affecting the system's stability [11]. Furthermore, the phenomenon of the 'duck curve', extensively observed in California, offers insight into future conditions and challenges related to electricity supply, such as the increasing need for rapid daily changes in power generation due to the presence of steep ramps in load curves [12,13], and the escalating unpredictability in market dynamics [14]. ...
... The back emf of the generator acts as a short-circuit for them. The virtual synchronous generator (VSG) imitates a mechanical synchronous generator and influences the real power P and the reactive Power Q in the grid as far as the installed power permits [5,6,7,8,9]. Two methods are compared in [8]. ...
... The virtual synchronous generator (VSG) imitates a mechanical synchronous generator and influences the real power P and the reactive Power Q in the grid as far as the installed power permits [5,6,7,8,9]. Two methods are compared in [8]. The signal flow graph in Fig. 1 explains the approach. ...
Installations of renewable energy systems like photovoltaic arrays and wind power generators are increasing in number. Problems may occur when such systems get installed on weak grids. Other than in major power distribution grids can sudden load changes endanger a stable operation of such systems. This is due to the high internal impedance of weak grids. The installation of virtual synchronous generators (VSG) stabilizes local grids. It absorbs the transients and existing current harmonics and also improves the power quality by compensating reactive components. Combined with fast current limitation, fault ride through (FRT) events are now possible , even with very fast switching inverters and their low inductance.
... Another comprehensive review of VSG-based controllers from a grid integration perspective has been presented in [24]. Furthermore, a detailed analysis of how VSGs can maintain the power system stability under very high renewable power penetration was presented in [25]. Moreover, control parameter selection has not been adequately justified in existing comparative studies conducted on VSGs [9]; hence, they do not provide a fair comparison [26]. ...
The virtual synchronous generator (VSG) is the most widely used grid-forming inverter (GFMI) control technique. The VSG can provide enhanced ancillary services and improved dynamic response compared to conventional synchronous generators and grid-following inverters (GFLIs). Developing an improved understanding of VSG strategies is vital to deploy them in the appropriate context in power grids. Therefore, this paper provides a rigorous comparative performance analysis of prominent VSG strategies (e.g., ISE-Lab, synchronverter, Kawasaki Heavy Industries (KHI) model, and power synchronisation control (PSC)) under different network conditions (e.g.,
X/R
ratios, network faults, and load types). Dynamic simulation studies have been carried out using a simplified test system to assess the performance of VSG models. Furthermore, comprehensive mathematical models of VSGs have been derived in order to verify the simulation results through a frequency domain stability analysis. Moreover, the offline simulation platform results have been validated in real-time using the IEEE-39 bus network on the OPAL-RT platform. According to the analysis, the synchronverter-based VSGs perform much better under low
X/R
ratios, fault conditions, and dynamic loads. Hence, they are more suitable for distribution grids and load centres with a high share of dynamic loads.
... Two alternative implementations exist. A first approach refers to those methods rooted in mathematical equations (e.g., synchronverters [8], [9], Kawasaki Heavy Industries [10], VISMA and IEPE topologies [9]). A second group relies on swing equations (e.g., Ise Lab's topology [11], the Synchronous Power Controller [5], [12], Virtual Oscillator Control [9]). ...
... Two alternative implementations exist. A first approach refers to those methods rooted in mathematical equations (e.g., synchronverters [8], [9], Kawasaki Heavy Industries [10], VISMA and IEPE topologies [9]). A second group relies on swing equations (e.g., Ise Lab's topology [11], the Synchronous Power Controller [5], [12], Virtual Oscillator Control [9]). ...
... A first approach refers to those methods rooted in mathematical equations (e.g., synchronverters [8], [9], Kawasaki Heavy Industries [10], VISMA and IEPE topologies [9]). A second group relies on swing equations (e.g., Ise Lab's topology [11], the Synchronous Power Controller [5], [12], Virtual Oscillator Control [9]). The Synchronous Power Controller (SPC) is a prevalent topology for virtual inertia implementation, synthesizing the electromechanical and electrical characteristics of a SG. ...
In this paper, a new method for the delay compensation when using an aggregation of virtual synchronous generators is proposed. Lack of inertia in power converters can potentially provoke stability issues that can be mitigated by the use of virtual inertia techniques. Among those, the Virtual Synchronous Generator (VSG) concept has received strong impulse in the last years. This paper is focused on the idea of using the distributed VSG concept in a renewable power plant, in which a single Synchronous Central Angle Controller (SCAC) is used for the power control exchange at the Point of Connection (PoC), while distribution control units are employed for the local inverter control. This idea, already discussed in the literature, is in here extended to consider the implementation on industrial string-level commercial power converters, recalling the importance of accessible measurements and communication delays. In order to validate the proposal, firstly communication delays are measured and modelled. Following, simulations with different SCAC operating modes are conducted, and finally experimental results validation of different operation modes with commercial converters are presented.
... Additionally, to minimize energy loss and improve the microgrid's voltage profile, authors in [10] used an Arithmetic Optimization Algorithm (AOA) to determine the ideal size of solar PV modules coupled with batteries. The frequency instability of isolated microgrids coupled with PVs may be mitigated using SI, which mimics a normal synchronous generator by using the rules that govern an inverter [11]- [13]. In this context, an innovative method for PV and SI scaling and location in microgrids utilizing Multi-objective Salp Swarm Optimization Algorithm (MOSSA) was presented in [14]. ...
The extensive use of fossil fuels, severe environmental implications, and increased transmission and distribution losses in traditional power networks have drawn attention to non-conventional energy sources. Photovoltaic (PV) units are currently playing a pivotal role in reducing power losses, enhancing voltage stability, and improving the reliability of power networks. However, unplanned and unregulated installation of PVs can cause major issues and challenges for power systems. These concerns include the likelihood of bidirectional power flow and the critical challenges, including frequency instability, energy losses, voltage instability, reactive power balance issues. Synchronverter (SI) is a contemporary method of addressing the frequency instability of isolated microgrids, which simulates a typical synchronous generator using the principles that control the inverter. This paper recommends a novel method of optimal PV unit sizing and placement in SI-integrated microgrids using an optimization method called the Differential Evolution Algorithm (DEA). The aim is to optimize the network nodes’ frequency deviation, active power loss, and voltage deviation. Moreover, this study assesses the SI-integrated 33-bus and 69-bus distribution networks. The findings reveal that the suggested methodology provides a suitable result by minimizing the frequency deviation, power loss, and voltage deviation with early convergence.
... However, this MPPT logic relies on the still prevalent presence of synchronous machines (SMs) in the grid and it may lead to frequency stability issues under large penetration of RESs. To tackle this issue, it is possible to make static converters more grid friendly, using proper control algorithms, such as the concept of virtual synchronous machine (VSM) [1], [2]. This way, electronic converters are enabled to provide key ancillary services to the grid, such as virtual inertia and reactive support during grid faults. ...
... A core function of VSMs is the so-called synthetic inertia [2]. This means that the VSM must inject active power proportional to the derivative of the grid frequency and its inertia constant : ...
Traditional power systems based on synchronous generators often feature low frequency electromechanical oscillations. However, the integration of renewable energy sources through power converters can help tackling this issue. In fact, thanks to the concept of virtual synchronous machine (VSM), it is possible to make the inverters behave as real synchronous machines (SMs). This way, the inverters can be integrated into the grid as traditional SMs and can even outperform them when it comes to damping low frequency oscillations in the power system. To do that, proper damping algorithms must be adopted in the VSM model. Therefore, this paper presents a simple and straightforward damping method for VSMs based on a single lead-lag filter acting on the VSM active power feedback. The proposed method and its integration in the VSM model are described. Moreover, a comparison method and four performance indices are proposed, to better evaluate the performance of the VSM damping methods. Finally, the proposed solution has been experimentally compared to five conventional methods to highlight its features according to the proposed performance indices.
... The typical scheme under study consists of a three-phase inverter connected to the grid through an LCL filter, as depicted in Fig. 1. Control algorithms based on the Virtual Synchronous Machine (VSM) concept allow grid-connected converters to behave like conventional SMs, by providing grid services [5]- [7]. ...
... In-order to overcome these challenges, Virtual Synchronous Generator (VSG) concept was developed [3] which mimics the behavior of SGs. To enhance the dynamic stability and system reliability, VSG control techniques and different topologies which improve its performance are discussed in [4], [5]. A detailed review of the active power support and inertia emulation by VSG models is undertaken in [6], where inertia support is provided through energy storage devices like flywheel [7], battery ESS [8], super-capacitor [9] and superconducting magnetic ESS [10], [11]. ...
... Renewable energy sources are connected to the power grid using power electronic converters [10,11]. Replacing conventional generators reduces the inertia of the power grid [12]. The inclusion of a large number of RESs creates difficulties with frequency stability [13], which is a major problem in their development [14,15]. ...
... The inclusion of a large number of RESs creates difficulties with frequency stability [13], which is a major problem in their development [14,15]. Improving the stability of the power system can also be achieved by using a virtual synchronous generator that minimizes the frequency fluctuations [12,16,17]. Battery energy storage systems (BESSs) can be used to simulate the inertia response of synchronous generators [12,18]. ...
... Improving the stability of the power system can also be achieved by using a virtual synchronous generator that minimizes the frequency fluctuations [12,16,17]. Battery energy storage systems (BESSs) can be used to simulate the inertia response of synchronous generators [12,18]. ...
This paper presents the models developed for the short-term forecasting of energy production by photovoltaic panels. An analysis of a set of weather factors influencing daily energy production is presented. Determining the correlation between the produced direct current (DC) energy and the individual weather parameters allowed the selection of the potentially best explanatory factors, which served as input data for the neural networks. The forecasting models were based on MLP and Elman-type networks. An appropriate selection of structures and learning parameters was carried out, as well as the process of learning the models. The models were built based on different time periods: year-round, semi-annual, and seasonal. The models were developed separately for monocrystalline and amorphous photovoltaic modules. The study compared the models with the predicted and measured insolation energy. In addition, complex forecasting models were developed for the photovoltaic system, which could forecast DC and AC energy simultaneously. The complex models were developed according to the rules of global and local modeling. The forecast errors of the developed models were included. The smallest values of the DC energy forecast errors were achieved for the models designed for summer forecasts. The percentage forecast error was 1.95% using directly measured solar irradiance and 5. 57% using predicted solar irradiance. The complex model for summer forecasted the AC energy with an error of 1.86%.
