Search

This paper describes three models developed through the Western Electricity Coordinating Council (WECC) SVC Task Force, to represent static Var systems (SVS) for power-flow and time-domain stability simulations. The goal was to develop a set of model structures that are generic, and can be easily parameterized to represent a variety of SVS systems. The term generic is used to imply a model structure that is not specific to a given vendor or equipment, and that is non-proprietary and public. These models have been implemented by several software vendors, and may soon be adopted by others. These models offer: 1) a suitable non-proprietary, not vendor specific set of models that can be used to evaluate SVS solution options for planning studies, and 2) the means to move away from the proliferation of user-written models that are becoming hard to manage in large interconnected power system models such as the WECC. The dissemination of the models and modeling documentation helps provide guidance to power system planners and operators about the latest SVS technologies and their application.

Injection of monoenergetic electron beams with uniform number density into an evacuated, straight-walled, equipotential cylindrical drift tubes has been modeled. An oscillating virtual cathode is produced by having the injected current exceed the space-charge limiting current of the drift tube. If the oscillation frequency of the virtual cathode exceeds the local beam plasma frequency a coherent traveling EM wave is launched with electric fields on the order of MeV/cm for an injected beam density of 1012 cm-3. Furthermore, in the absence of a strong axial magnetic field transmitted particles are autoaccelerated up to 3 times their initial kinetic energy.

Several aspects of the laser electron accelerator concept are studied. The minimum laser intensity necessary for electron trapping is strongly dependent on frequency. A pulse length equal to the plasmon wavelength (2? ?p-1) produces significantly better acceleration than one with half that length. Relativistic plasma effects enhance acceleration and increase the maximum accelerating field. If the laser risetime or intensity is such that electron trapping does not take place, plasma heating by the nonlinear ponderomotive force still occurs producing suprathermal electrons. Application of this mechanism to microwaves has severe drawbacks.

One-dimensional relativistic and electromagnetic simulations show the Plasma Beatwave Accelerator to be a viable approach to obtaining large accelerating fields. The plasma wave excited by Raman Forward Scattering has a longitudinal electric field on the order of 100 MeV/cm to 10 GeV/cm based on plasma densities of 1016 cm-3 to 1020 cm-3. The use of optical mixing to grow a plasma wave of the proper frequency above the noise level greatly reduces the laser intensity needed to drive the Raman instability. TeV energies for plasma electrons or preaccelerated charged particles in short distances appear feasible. Results where an injected electron beam is accelerated coherently from 1 MeV to 20 MeV in one millimeter are presented. Two-and three-dimensional effects must still be resolved.