In order to solve the problem that voltage source converter based multi-terminal direct current (VSC-MTDC) system cannot provide inertia and participate in frequency modulation after connecting AC power grid under traditional control strategy, an adaptive strategy on virtual is proposed. First, relationship between DC was established by a control, allowing VSC-MTDC side. Second, address limited...

<p>Planning of high voltage direct current (HVDC) grids requires inclusion reliability assessment alternatives under study. This paper proposes a methodology to evaluate the adequacy source converter/VSC-HVDC networks. The analyses performance system using N-1 and N-2 contingencies in order detect weaknesses DC network evaluates two types remedial actions keep entire acceptable operating ...

Adipose tissue-derived stem cells (ADSC) are routinely isolated from the stromal vascular fraction (SVF) of homogenized adipose tissue. Similar to other types of mesenchymal stem cells (MSC), ADSC remain difficult to define due to the lack of definitive cellular markers. Still, many types of MSC, including ADSC, have been shown to reside in a perivascular location, and increasing evidence shows...

Voltage source converters (VSCs) are highly vulnerable to DC fault current; thus, protection is one of the most important concerns associated with the implementation of multi-terminal VSC-based DC networks. This paper proposes a protection strategy for medium voltage DC (MVDC) distribution systems. The strategy consists of a communication-assisted fault location method and a fault isolation sch...

In this paper, a global stability and robust nonlinear controller for VSC-HVDC transmission Converters applying input-output linearization (IOL) techniques is proposed. The feedback linearization based nonlinear differential-geometric techniques is used to cancel nonlinearities and decouple the input control variables. Global tracking capability with zero steady-state error of the voltage loop ...

This paper presents the analyzed results of using a high-voltage directcurrent (HVDC) link based on voltage-source converter (VSC) to achieve damping improvement of four parallel-operated doubly-fed induction generator (DFIG)-based offshore wind farms (OWFs) fed to a large power grid. A frequency-domain scheme based on eigenvalue analysis is carried out and a time-domain method based on nonline...

Resonances can have negative impact on a Voltage Source Converter-High Voltage DC (VSC-HVDC) system. This paper develops dc impedance models for the rectifier and inverter stations for a VSC-HVDC system when they are viewed from a dc terminal. The impedance models take converter controllers into account. The derived impedance models are validated by comparing frequency responses of the analytic...

This paper focuses on a second order sliding mode based direct power controller (SOSM-DPC) of a three-phase grid-connected voltage source converter (VSC). The proposed control scheme combined with fuzzy logic aims at regulating the DC-link voltage of the converter and precisely tracking arbitrary power references, in order to easily control the system’s power factor. Therefore measures are prop...