Optimal reactive power allocation in an offshore wind farms with LCC-HVdc link connection

Information gap decision theory based OPF with HVDC connected wind farms

“…• Cost benefit analysis for the operational benefits against the investment costs of HVDC systems [26] • Opportunity cost of wind power shortage & surplus [27] • Cost of environmental benefit loss [27] • Minimizing losses within the wind farm and the HVDC transmission system and maximizing production [28] • Expected penalty cost for wind power curtailment [29] • Expected cost of calling up power reserves because of wind power shortage [29] • Risk due to expected energy not supplied (EENS) and total operating costs [30] • Location marginal prices, and reserve costs [30] • Voltage regulation of the electrical grid [31] C. Contributions…”

Stochastic Multiperiod OPF Model of Power Systems With HVDC-Connected Intermittent Wind Power Generation

“…• opportunity cost of wind power shortage & surplus [9] • cost of environmental benefit loss [9] • expected penalty cost for not using all available wind power [10] • expected cost of calling up power reserves because of wind power shortage [10] • risk due to expected energy not supplied (EEENS) and total operating costs [11] • location marginal prices, and reserve costs [11] • minimizing losses within the wind farm and the HVDC transmission system and maximizing production output [12] • voltage regulation of the electrical grid to which farms are connected [13] The proposed approaches for handling the uncertainty of wind power generation are summarized as follows: Monte Carlo [9], triangular approximate distribution (TAD) [11], scenario based modeling [14], [15].…”

“…Capability Curve of DGIFs 1) Stator current limit: this limit models the stator heating due to the stator winding Joule losses. By considering all quantities in per-unit (pu), the relation between stator voltage, current and active/reactive power outputs can be expressed as follows [12]:…”

“…Xst is the no-load reactive power absorption, which means that the DFIG becomes unstable when the reactive power consumption is greater than the no-load reactive power [12].…”

“…The grid-side inverter of the DFIG is usually operating with a unity power factor [12]. Hence, the injected power from the rotor is zero, and total reactive power output of DFIG is as follows:…”