Control of multi-terminal HVDC networks towards wind power integration: A review

Abstract

More interconnections among countries and synchronous areas are foreseen in order to fulfil the EU 2050 Target on the renewable generation share. One proposal to accomplish this challenging objective is the development of the socalled European SuperGrid. Multi-terminal HVDC networks are emerging as the most promising technologies to develop such a concept. Moreover, multiterminal HVDC grids are based on highly controllable devices, which may allow not only transmitting power, but also supporting the AC grids to ensure a secure and stable operation. This article aims to present an overview of different control schemes for multi-terminal HVDC grids, including the control of the power converters and the controls for power sharing and the provision of ancillary services. The article also analyses the proposed modifications of the existing control schemes to manage high participation shares of wind power generation in multi-terminal grids.

Optimal Power Flow in Hybrid AC and Multi-terminal HVDC Networks with Offshore Wind Farm Integration Based on Semidefinite Programming

“…There are several different control strategies for MT-HVDC system including master-slave control, margin voltage control, priority control, ratio control and droop control [2]. This paper adopts master-salve control scheme for AC/DC terminals.…”

“…Wind energy has become an important electric power source nowadays due to its cost-effectiveness and environmental friendliness [1]. In addition to the onshore wind farms, offshore wind farms also draw a lot of attention because of better wind quality and limited inland sites to build new wind farms [2]. High voltage direct current (HVDC) technology is one of the most favorable options for the integration of offshore wind farms to deliver the power for inland customers [3].…”

Multi-terminal DC grids: challenges and prospects

“…Voltage-droop control is the most commonly employed technique for direct voltage control of MTDC grids according to the literature [35]. This very simple control technique can be also used in a generalized manner to bring enhanced flexibility to the control and operation of the MTDC grid [36].…”

“…Despite the popularity of the voltage-droop control technique, inspired by frequency-droop control in AC power systems [35,39,40], it suffers from some drawbacks. The main one lays on the fact that it cannot perform fixed power control for a particular power converter station or fixed direct voltage control in some operation modes.…”

Dynamic Overload Capability of VSC HVDC Interconnections for Frequency Support

“…Provision of network services such as frequency support and power oscillation damping through VSC HVDC has been reported extensively [12] with some papers focusing specifically on MMC-based HVDC [13], [14]. In these works, the headroom for dynamic modulation of active/reactive power was made available by either considering the expensive option of de-loaded operation (below the rated capacity of the converter, e.g.…”