A model-based controller in rotating reference frame for Hybrid HVDC

Abstract

In this paper, a model-based controller is proposed for Hybrid HVDC, Hybrid comprising a Voltage Source converter (VSC) using in the sending side and Line-commutated Converter (LCC) using in the receiving side. This type of HVDC may be applied when power is only in one direction for example HVDC for offshore wind farm applications. VSC controls directly the instantaneous active and reactive power using a synchronous reference frame controller while the LCC maintains the DC voltage using a proportional-integral (PI) controller. It also proposed in this paper, when AC grid is weak, to replace the LCC for a capacitor commutate converter (CCC) because of the additional commutation voltage reduces the risk of commutation failure. PSCAD/EMTDC simulations are provided to illustrate the performance of the proposed controller under normal operation and severe disturbance such as three phase-to-ground AC and DC faults.

Three-terminal Hybrid HVDC Transmissions Control Strategies for Bundled Wind-thermal Power Plants

“…Dynamic performance of a VSC based series hybrid HVDC has been studied for supplying a weak AC system [12]. Controller designing for a hybrid HVDC system with a LCC and VSC has been proposed [13]. Author in [14] discussed the mathematical mode and operational mechanism of a hybrid HVDC link.…”

Particle swarm optimization based PI controller of VSC-HVDC system connected to a wind farm

“…Compared to conventional line commutated HVDC systems, the principal characteristics of VSC transmission are (Xu et al 2007;Torres-Olguin et al 2010) as follows.…”

A direct power control for Hybrid HVDC transmission systems

“…In [4] and [5] the DC current is regulated, but the controller are not explicitly presented. In [3] and [6] a synchronous reference frame (SFR) controller was proposed. In the SFR basically, two PI are utilized in the current inner loop, while additional PIs are used for the active and the reactive control outer loop.…”

“…In [2] a simple integrator is utilized to regulate the DC voltage. In [3] a PI controller is used to maintain constant the extinction angle, while in [6] a PI is used to regulate the DC voltage through a reference. In this work, a model-based Direct Power Controller (DPC) is proposed for the VSC in the Hybrid HVDC.…”