Interoperability of classical and advanced controllers in MMC based MTDC power system

This paper presents the modular-multilevel-converter (MMC) control interoperability (IOP) and interaction within the High Voltage Direct Current (HVDC)-based power system. IOP is a crucial issue in the large-scale HVDC grid with different suppliers. To accommodate future multi-vendor HVDC grids developments, this article comprehensively...

Two-layer control structure for enhancing frequency stability of the MTDC system

This paper explores the possibilities of providing fast frequency support as an emergency support service to the disturbed AC system through the MTDC grid. A two-layer hierarchical control structure of the MTDC grid is proposed to assure the minimum cost of the frequency control actions, the minimum voltage deviations, or the minimal impact...

Model predictive control and protection of MMC-based MTDC power systems

Meshed offshore grids (MOGs) present a viable option for a reliable bulk power transmission topology. The station-level control of MOGs requires faster dynamics along with multiple objective functions, which is realized by the model predictive control (MPC). This paper provides control, and protection design for the Modular Multilevel...

Sliding Mode Control of the MMC-based Power System

The modular multilevel converter has become a popular topology for many applications in medium and high-power conversion systems such as multi-terminal direct current power systems. In this paper, Modular multilevel converter structure and related equations are presented. Then, control methods for circulating current, output current, and...

Robust Adaptive Back-Stepping Control Approach Using Quadratic Lyapunov Functions for MMC-Based HVDC Digital Twins

Due to its excellent performance, VSC-based high voltage direct current (HVDC) power systems draw significant attention. They are being heavily used in modern industrial applications, such as onshore and offshore wind farms, and for interconnection between asynchronous networks. However, the traditional proportional-integral (PI) control...

EMT Real-Time Simulation Model of a 2 GW Offshore Renewable Energy Hub Integrating Electrolysers

Due to their weak nature, such as low inertia, offshore energy hubs are prone to unprecedented fast dynamic phenomena. This can lead to undesired instability problems. Recent literature, with main focus on onshore systems, suggests that electrolysers could be an attractive option to support wind generators in the mitigation of balancing problems...

Microsecond enhanced indirect model predictive control for dynamic power management in mmc units

The multi-modular converter (MMC) technology is becoming the preferred option for the increased deployment of variable renewable energy sources (RES) into electrical power systems. MMC is known for its reliability and modularity. The fast adjustment of the MMC’s active/reactive powers, within a few milliseconds, constitutes a major research...

Generic EMT Model for Real-Time Simulation of Large Disturbances in 2 GW Offshore HVAC-HVDC Renewable Energy Hubs

This paper proposes a Electro-Magnetic Transient (EMT) model of a 2 GW offshore network with the parallel operation of two Modular Multi-level Converter (MMC)—High Voltage Direct Current (HVDC) transmission links connecting four Offshore Wind Farms (OWFs) to two onshore systems, which represent a large scale power system. Additionally, to...

MPC Based Centralized Voltage and Reactive Power Control for Active Distribution Networks

The paper presents an approach for online centralized control in active distribution networks. It combines a proportional integral (PI) control unit with a corrective control unit (CCU), based on the principle of Model Predictive Control (MPC). The proposed controller is designed to accommodate the increasing penetration of distributed...

Assessment of Dynamic Measurement Intervals for State Estimation in Future Distribution Systems

The ongoing energy transition introduces new load and generation units like photovoltaic generation in the medium-voltage systems network. These generation units increase the variance of the power injections, resulting in increased stochasticity of the power flow values. For confident assessment of the system’s operating condition, a measurement...

Stability Analysis of High-Frequency Interactions Between a Converter and HVDC Grid Resonances

This paper analyzes high-frequency interactions between a Modular Multilevel Converter (MMC) and High Voltage Direct Current (HVDC) grid resonances by studying their effect on the system stability. The recent appearance of converter-related instabilities due to high-frequency oscillations at the converter's ac side raises concerns about whether...

Adaptive Control of HVDC Links for Frequency Stability Enhancement in Low-Inertia Systems

Decarbonization of power systems has put Renewable Energy Sources (RES) at the forefront when it comes to electric power generation. The increasing shares of converter-connected renewable generation cause a decrease of the rotational inertia of the Electric Power System (EPS), and consequently deteriorate the system capability to withstand large...