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Fast frequency response (FFR) is an option in maintaining system security under low inertia conditions. Power electronics interfaced energy resources such as wind and photovoltaics have the capability to deliver FFR. At present, almost all installed power electronics interfaced energy resources are connected to the grid by the phase locked loop (PLL)-synchronized voltage source converter (VSC) and they usually implement inertial response by measuring the rate of change of frequency (RoCoF). However, RoCoF measurements are highly susceptible to disturbances in the grid. In this paper, a novel inertia controller is developed for PLL-synchronized VSC interfaced energy resources to implement natural inertial response without measuring RoCoF. A thorough stability analysis is performed to study the impact of proposed inertia controller on the VSC in weak grid. The proposed inertia controller makes the deviation of DC voltage proportional to the deviation of system frequency. Further, a method of primary frequency control is proposed by measuring DC voltage rather than grid frequency. The proposed FFR scheme of inertia and primary frequency control is applied to a direct-drive windfarm connected to a grid, and its correctness and advantages are verified by simulation. [ABSTRACT FROM AUTHOR]

An annealing method capable of forming highly activated shallow junctions in Ge CMOS is still lacking. For the first time, nonmelt submillisecond laser spike annealing (LSA) is demonstrated to achieve high activation level, excellent diffusion control, and resulting low contact resistivity for both n-type and p-type Ge junctions when using P and B as the dopants, respectively. The thermal stability of the junctions activated by LSA is investigated. In addition, our results on Ge junctions and contacts are benchmarked systematically against published results using sheet resistance-junction depth ( Rs-{X}{\!{j}} ) plots and contact resistivity-dopant concentration ( \rho c-{N} ) plots. [ABSTRACT FROM PUBLISHER]