A measurement based comparison of full-wave and quasi-static methods for baseband modeling of plated through hole via structures

As signaling rates increase, the usable bandwidth of modern telecommunication and storage systems is bounded by parasitic elements within the signal path. To improve data throughput, system designers use cascaded combinations of equivalent circuit models obtained through component level simulation and measurement to evaluate the communications channel. The analytical methods used to create these models have frequency dependent limitations and restrict applications. To this end, a measurement based comparison of quasi-static and full-wave simulation methodologies was performed on plated through hole via structures in a printed circuit board over a frequency range of 0.1GHz to 20GHz. Test fixtures and calibration standards, which isolate the behavior of the component under test from the measurement set-up, are required to establish performance metrics used for the evaluation. In this study, a printed circuit board was designed and fabricated to contrast two different calibration methodologies as applied to plated through hole via structures. The results of this study will describe the usable bandwidth associated with equivalent circuit models derived from quasi-static electromagnetic simulations while demonstrating strong correlation between the full-wave electromagnetic models and measured scattering parameters of a plated through hole via structure

Hardware-in-the-loop simulations and control designs for a vertical axis wind turbine

Control designs play an important role in wind energy conversion systems to achieve high e ciency and performance. In this study, hardware-in-the-loop simulations (HILS) are carried out to design control algorithms for small vertical axis wind turbines (VAWT). In the HILS, the wind torque is calculated from the power coe cient of an experimental VAWT and applied to a motor that drives the generator in the VAWT simulator, which mimics the dynamics of the real VAWT rotor. To deal with the disturbance torques in the VAWT simulator, a virtual plant was introduced to obtain an error between the speeds in HIL system and the plant. This error is used to generate a disturbance torque compensation signal by a proportional-integral (PI) controller. The VAWT simulator successfully mimics the dynamics of the VAWT under various wind speed conditions and provides a realistic framework for control designs. A maximum-power-point-tracking (MPPT) and a proposed simple non-linear control are presented for the control of the VAWT. The control algorithms were tested in the HILS under step up-down, sinusoidal and realistic wind conditions. The output power results are compared with each other and the numerically estimated optimum values. The effects of the permanent-magnet synchronous generator (PMSG) parameters on the system e ciency were investigated, and a performance comparison in numerical simulation was made between the present PMSG and two other generators available in the market