This paper presents a new methodology for a weak grid is to make possible the addition of voltage source converters more effective. The controller is mainly composed of two parts, namely linear power damping and synchronizing controller and a supplementary nonlinear controller. The first part synchronizes a voltage source converter (VSC) to the grid by supplying damping and synchronizing power ...

The multilevel cascaded converters are extensively applied for high-voltage and high-power applications, which are considered as the most favorable topologies for the high power ac-drives and the high-voltage DC transmission (HVDC) systems using the voltage source converters (VSCs). This paper presents the dc capacitor balancing and effective current regulation methodologies for the multilevel ...

The scope of the presented paper is concentrated on two terminal HVDC transmission system. The intention of the paper is to present a precise insight into the limitations of the transmitted power of a HVDC system incorporated in real AC power system. The paper demonstrates the impacts of the combined AC/DC system model parameters on the transmitted power through the DC link. Also, in this paper...

In this paper Power system stability enhancement through static synchronous compensator (STATCOM)based controller is investigated. The potential of the STATCOM supplementary controllers to enhance thedynamic stability is evaluated. The design problem of STATCOM based damping controller is formulatedas an optimization problem according to the eigenvalue based objective function that is solved by...

Voltage Source Converter (VSC) based HVDC is the most recent HVDC technology with extruded DC cables in small and medium power transmission. VSC-HVDC converters include Insulated Gate Bipolar Transistors (IGBT’S) and operated with high frequency Pulse Width Modulation (PWM) in order to get high speed control of both active and reactive power. With VSC-HVDC there is an addition degree of freedom...

Converter transformers are the key and the most important components in high voltage direct current (HVDC) power transmission systems. Statistics show that the failure rate of HVDC converter transformers is approximately twice of that of transformers in AC power systems. This paper presents an approach integrated with a two-dimensional cloud model and an entropy-based weight model to evaluate t...

This paper analyses reliability data of HVDC systems of Southern China Power Grid. The weak links of HVDC systems’ operational reliability are DC control and protection, valve hall and valve cooling system and transmission lines. Some improvement measures and HVDC system reliability technology are proposed in this paper.

Wind energy has huge potential to become major source of renewable energy for the modern world. For integrating wind farms to the AC grid, HVDC transmission systems have several advantages over AC transmission systems. This paper presents the design and control of voltage source converter based HVDC system for integration of wind farms in to AC grid. The designed VSC-HVDC system performance und...

In the northwest of China, a strategy to transmit wind-thermal–bundled power from local grid and doubly fed induction generator (DFIG)–based wind farms through voltage source converter–based HVDC (VSC-HVDC) can be widely applied. However, since is usually weak, new type electrical oscillation in medium-frequency region may occur sending-end converter (SEC) VSC-HVDC with PQ-control. The mechanis...