Pilot/vehicle model analysis of visual and motion cue requirements in flight simulation

The optimal control model (OCM) of the human operator is used to predict the effect of simulator characteristics on pilot performance and workload. The piloting task studied is helicopter hover. Among the simulator characteristics considered were (computer generated) visual display resolution, field of view and time delay

Adjustable inertial response from the converter with adaptive droop control in DC grids

In a DC grid, the inherent inertial support from the DC capacitors is too small to resist step changes or random fluctuations from the intermittent power resources, which results in lower DC voltage quality. In this paper, an adaptive droop control (ADC) strategy is proposed to achieve an increased inertia from the droop controlled converter. The adaptable droop coefficient according to the DC voltage variation enables fast swing of the droop curve, so that the converter can provide inertial power for the DC grid like synchronous generators in AC grids. The design of the ADC including the calculation and limitation of the adaptable droop coefficient is analyzed in detail. The small-signal analysis of the DC grid with ADC is provided to identify its stability issue. Experimental tests on a controller hardware-in-the-loop (HIL) platform of a low-voltage (LV) DC grid are carried out to validate the proposed method. In this LV DC grid, the proposed ADC is implemented on the energy storage system (ESS) which provides inertial support to improve the DC voltage quality under different power fluctuations, and smooths the power transmitted to AC grid

Preliminary design of a 100 kW turbine generator

The National Science Foundation and the Lewis Research Center have engaged jointly in a Wind Energy Program which includes the design and erection of a 100 kW wind turbine generator. The machine consists primarily of a rotor turbine, transmission, shaft, alternator, and tower. The rotor, measuring 125 feet in diameter and consisting of two variable pitch blades operates at 40 rpm and generates 100 kW of electrical power at 18 mph wind velocity. The entire assembly is placed on top of a tower 100 feet above ground level