Stability Analysis of Converter Control Modes in Low-Inertia Power Systems

Chu

IEEE Trans. Sustain. Energy

et al. 2019

Self Cite

152

This paper presents a novel virtual synchronous machine controller for converters in power systems with a high share of renewable resources. Using an LQR-based optimization technique, the optimal state feedback gain is determined to adaptively adjust the emulated inertia and damping constants according to the frequency disturbance in the system, while simultaneously preserving a trade-off between the critical frequency limits and the required control effort. Two control designs are presented and compared against the open-loop model. The proposed controllers are integrated into a state-of-the-art converter control scheme and verified through EMT simulations.

Section: Modeling and Control Designmentioning

confidence: 99%

“…The complete mathematical model consists of 13 states and is implemented in per unit. More details on the overall converter control structure and employed parametrization can be found in [15], [16], [20].…”

Section: Modeling and Control Designmentioning

confidence: 99%

LQR-Based Adaptive Virtual Synchronous Machine for Power Systems With High Inverter Penetration

Chu

IEEE Trans. Sustain. Energy

et al. 2019

Self Cite

152

“…The proposed adaptive VSM controller is implemented within a state-of-the-art VSC control scheme previously described in [19]. The outer control loop consists of active and reactive power controllers providing the output voltage angle and magnitude reference by adjusting the predefined setpoints according to a measured power imbalance.…”

Section: E System Modeling and Control Implementationmentioning

confidence: 99%

Interval-Based Adaptive Inertia and Damping Control of a Virtual Synchronous Machine

2019 IEEE Milan PowerTech

Hug

2019

Self Cite

This paper presents a novel virtual synchronous machine controller for converters in power systems with a high share of renewable resources. Using an interval-based approach, the emulated inertia and damping constants are adaptively adjusted according to the frequency disturbance in the system, while simultaneously keeping the frequency within prescribed limits. Furthermore, the sufficient stability conditions for control tuning are derived. The proposed design is integrated into a stateof-the-art converter control scheme and tested through timedomain simulations. A comparative study against the existing approaches in the literature verifies the control effectiveness.

“…We consider a state-of-the-art VSC control scheme previously described in [24], where the outer control loop consists of droop-based active and reactive power controllers providing the output voltage angle and magnitude reference by adjusting the predefined setpoints (x * ) according to a measured power imbalance. Subsequently, the reference voltage vector signal…”

Section: A Vsc Control Schemementioning

confidence: 99%

“…The complete mathematical model consists of 15 states, with inclusion of the filter current and voltage dynamics, and is implemented in a rotating (dq)frame and per unit. More details on the overall converter control structure, employed parametrization, potential operation modes and respective transient properties can be found in [24].…”

Section: A Vsc Control Schemementioning

confidence: 99%

Robust Converter Control Design under Time-Delay Uncertainty

Flores

2019 IEEE Milan PowerTech

et al. 2019

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This paper deals with the converter control design under time delay uncertainty in power systems with high share of converter-based generation. Two approaches for time delay modeling are proposed using linear fractional transformations and linear parameter-varying systems, respectively. Subsequently, two output-feedback synthesis methods are implemented based on H∞ control theory, and formulated using linear matrix inequalities: (i) a norm-bounded parametric H∞ controller; and (ii) a gain-scheduled H∞ control. These robust control principles are then employed to improve the performance of Voltage Source Converters (VSCs) under varying measurement delays. Three novel control strategies are proposed in order to redesign the conventional inner control loop and improve converter performance when dealing with measurement uncertainty. Finally, the controllers are integrated into a state-of-the-art VSC model and compared using time-domain simulations.