Effects analysis of excitation circuit on power control for VSG: a design‐oriented study

Abstract

Reactive power control loop (RPCL) in virtual synchronous generator (VSG) plays the role of excitation circuit in conventional SG. The control strategy improvement or parameters configuration method of RPCL is always the emphasis of analysis. However, the impacts of RPCL on VSG system performance are usually overlooked. On the basis of that, this study aims to investigate the effects of RPCL on power control performance. First, a simplified SG model is established and implemented to VSG. Then, VSG system modelling with state equations in power control time scale is elaborated. The excitation current in the modelling is regarded as one crucial state variable to identify the effects of the excitation circuit on VSG system. Eigenvalue locus analysis and eigenproperties analysis reveal how the excitation circuit affects power oscillation damping performance and even results in power coupling issue of power control. The effects of operating points on system power control are also taken into account. Finally, the experimental results are given to verify the theoretical analysis.

Current Sensor-Less Virtual Synchronous Generator Model Predictive Control Based on Sliding Mode Observer

“…Content may change prior to final publication. the output voltage of the VSG [7][8][9][10]. However, many PI controllers are required, which makes the system difficult to design and debug.…”

“…Here, it is assumed that the current meet the condition shown in (7) as the amplitude and frequency of the current are changed slowly during a control period. To enhance the fault-tolerant operation ability of the VSG and achieve a comparable performance without using the inductor current sensor, a new current sensor-less VSG-MPC scheme is proposed as follows based on (7).…”

“…Rencently, many relevant studies on VSG technologies have been published [4][5][6][7][8][9][10]. Typically, there are two types of VSG control technologies.…”

“…Then, a modulation voltage is generated, which is fed into the pulse-width modulation block to control the inverter [2][3][4][5][6]. In the other type, there are often three control loops [7], including an outer power loop, which is used to adjust the frequency and the voltage, a middle voltage control loop, which is used to control the voltage of the filter capacitor, and an inner current loop, which takes the output current of the middle voltage control loop as the reference to control the output current of the inverter. Finally, a modulation voltage is generated by the inner current loop, which is fed into the pulse-width modulation block to control the inverter [8][9][10].…”

Guest Editorial: Challenges in Future Grid‐Interactive Power Converters: ControlStrategies, Optimal Operation, and Corrective Actions

“…To promote grid support performance, other novel control schemes are also proposed in this Special Issue. Paper [13] analyses the impact of reactive power excitation coefficient effects on dynamic and steady‐state performance of system power control and presents experimental verification results. Paper [14] presents a parameter tuning for dynamic digital twins in an inverter‐dominated distribution grid based on the neural network.…”