Zero-sequence current suppression control for fault current damper based on model predictive control

In a multi-terminal direct current (MTdc) system based on a modular multilevel converter (MMC), high-speed and large interruption capability direct current circuit breakers (dc CBs) are required for dc fault interruption. However, commercializing these breakers is challenging, especially offshore, due to the large footprint of the surge...

Single-ended DC Fault Location Method For MMC-Based HVDC Power System Using Adaptive Multi-step Levenberg-Marquardt Algorithm

This article presents an accurate DC fault location method that applies parameter fitting. This technique first discusses the traveling wave (TW) propagation process in the decoupled line-mode network. We obtain the exact fault distance equation based on the analytical expressions for the wavefront of backward line-mode voltage TW. The adaptive...

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...

Post DC Fault Circulating Current Suppression Control

The radial topology of the Multi-terminal High Voltage Direct Current (MTDC) power system is a preferred connection for the gigawatt- renewable power due to its scalability and reliability. However, a radial topology with a metallic return bipolar converter configuration MTDC network possesses technical challenges regarding DC fault current...

A Clarke-Wavelet-Based Time-Domain Power Transformer Differential Protection

Phasor-based differential protection is widely used as the main protection function of the power transformer due to its reliability and ability to discriminate internal from external faults and inrush currents. However, these methods present some delays due to phasor convergence during the fault occurrence and can fail during challenging...

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...

Supplementary control based on current source coupling for improving dynamic characteristics of active distribution network

Supplementary control (SC) technology is widely leveraged by power supply companies in active distribution networks (ADNs) to improve their stability and dynamic characteristics. Yet, the existed SCs are generally implemented from inside the converter controllers of distributed generators (DGs) or active loads, so there is a need to redesign...

S-Transform based fault detection algorithm for enhancing distance protection performance

This paper presents a new fault detection algorithm based on the Fast Discrete Stockwell Transform. The algorithm can improve the functionality of existing distance protection and resolve shortcomings identified during the fault detection process in case of fault occurrence in systems with a high penetration of power electronics-based generators...

PMU-voltage drop based fault locator for transmission backup protection

Local protection elements such as fuses and relays are the first protective mechanism to clear the fault and isolate the affected part of the power grid. Although the selectivity, speed, and sensitivity of these primary protection devices are relatively high, they cannot be considered flawless. There is a small percentage of events for which...

Real-time simulation Model of Ultracapacitors for Frequency Stability Support from Wind Generation

The frequency stability of the power system is challenged by the high penetration of power electronic interfaced renewable energy sources (RES). Energy storage systems (ESS) are used to supply extra power injection to enhance the frequency stability during a disturbance. This paper presents a novel approach for improving the frequency dynamics...

Hardware-in-the-loop based testing of wind turbine controllers for transient stability enhancement

Traditionally, electrical power systems have been based on fossil-fuel fired generation plants to satisfy the load demand. However, due to environmental targets for significant CO2 reduction, a gradual decommission of the aforementioned plants is observed whereas renewable energy sources are gaining gradually increasing momentum, which entails...

Fast Active Power-Frequency Support Methods by Large Scale Electrolyzers for Multi-Energy Systems

This paper presents a comparative assessment of fast active power regulation (FAPR) control strategies implemented on megawatt-scale controllable electrolysers, with the goal of achieving enhanced frequency support during large active power imbalances that lead to major under-frequency deviations. The FAPR control strategies consist of three...

Implementation and Performance Assessment of Fast Active Power Injection Method for Type 4 Wind Turbine based on Real-time Simulation

This paper deals with the implementation of a Fast Active Power Injection (FAPI) controller in a Type-4 Wind Turbine. Two different FAPI controllers, droop-based and a modified derivative-based controller are proposed and investigated under real-time simulation platform. The implementation is done in a Real-Time Digital Simulator (RTDS) by...

Modelling of Large Size Electrolyzer for Electrical Grid Stability Studies in Real Time Digital Simulation

This paper provides an overview on implementing practical models of large scale electrolysers (>1MW) for real time digital simulation. The search for new sources of ancillary services has aroused considerable interest in the use of large scale electrolysers for power system ancillary services. As the number of large scale electrolysers is...

Synchronized measurement technology supported AC and HVDConline disturbance detection

In electric power system, disturbance detection has become an important part of grid operation and refers to the detection of a voltage and current excursion caused by the wide variety of electromagnetic phenomena. This paper proposes a computationally efficient and robust algorithm for synchronized measurement technology (SMT) supported...