AC fault ride-through capability of a VSC-HVDC transmission systems

Abstract

This paper presents a recovery strategy that enables DC transmission systems based on voltage source converters to ride-through different ac faults with minimum current and voltage stresses on the converter switching devices. The proposed recovery strategy eliminates the trapped energy in the dc link during ac faults; as a result the rise in the dc link voltage is prevented. This may eliminate the need for the dc chopper in the dc link, as proposed in the literature, to dissipate the trapped energy. To demonstrate the effectiveness of the recovery strategy, several fault conditions are considered, including, symmetrical and asymmetrical faults. The proposed recovery strategy improves the resiliency of the VSC-HVDC transmission system to different ac faults, which can be summarized as follows: limited current contribution to the fault and limited current and voltage stress on the switching devices as the rise in the dc link voltage is significantly reduced or prevented

A review of control methods for providing frequency response in VSC-HVDC transmission systems

“…Furthermore, there are other advantages of HVDC,, particularly with respect to power system stability [15][16][17][18]:…”

A new fault-ride-through strategy for MTDC networks incorporating wind farms and modular multi-level converters

“…Based on this principle, many different approaches have been proposed [15,17,14,18,19], all aiming at avoiding the use of additional equipment, and therefore lowering the cost and power losses. It is noted, though, that there are numerous challenges yet to be considered including properly handling mechanical stresses, overcoming the need for communication signals to achieve faster responses, and addressing the frequency/angular stability issues of the AC system.…”

Enhanced Instantaneous Power Theory for Control of Grid Connected Voltage Sourced Converters Under Unbalanced Conditions

“…Additionally, the VSC is also expected to deal with harmonic distortion, following network recommendations and standards [13][14][15][16][17][18][19][20].…”

“…They should attend the increasing demands related to low-voltage-ride-through capability, with minimized impact on the power transfer [13,14].…”