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Filter networks for long cable drives have been studied in the last decade to solve the over-voltage problem at the motor terminals. However, little research has been dedicated to analyze their influence on the voltage distribution in the motor stator winding and on the circulation of the common-mode currents. In this paper, the project of dvldt filters through simulation and analysis from previous works is extended including the motor voltage distribution and commonmode current analysis. Simulation and experimental results are presented demonstrating the usefulness of the filter networks on the motor over-voltage mitigation. Three filter topologies will he discussed and compared here: RLC Filter at the motor terminals, RLC Filter at the inverter output and Reactor Filter, which is extensively used in the industry. Simulation and experimental results demonstrates that the RLC Filter at the inverter output is the most interesting solution among the main types of passive filter networks. KEYWORDS Industrial Drives; Electrical Drive Systems Design and Applications; Over-voltage and dvldt Filter Design. ~:.INTRODUCTIONThe main goal of this paper is to demonstrate that the RLC Filter at the inverter output is the most interesting passive solution to mitigate the' existent over-voltage problem in the actual adjustable speeddrives [l], [21, [31, [41,[5]. The passive dv/dt filters have k e n fully exploited in previous works [6], [7], in which a convenient simulation tool has been suggested to design filter networks through simulation and analysis. In this paper, other figures of merit are added to this design process: the voltage distribution in the machine stator winding and the common-mode current circulation.The filter network compkisons also include the 5% reactor filter, a standard dv/dt filter output in industry. The dv/dt filter topologies are designed for a 3 hp induction motor drive system with 250 meters of power cable length. Selected simulation and experimental results are presented showing the usefulness of the filters. It will be shown that the RLC Filter placed at the inverter output presents the best agreement among the conflicting goals: minimal over-voltage, minimal filter losses, minimal common-mode currents and better voltage distribution in the machine stator winding, FILTER DESIGN THROUGH SIMULATIONA N D ANALYSIS It's known that the main philosophies utilized to solve the over-voltage problem are: to match the load to the cable Thomas A. Lip0 Gin Venkataramanan UW-Madison ECE Department 1415 Engineering Dr. Madison, WI, 53706 -USA characteristic impedance and to increase the voltage pulse rise time [7], [SI, [91. The networks placed at the motor terminals follow the first philosophy. On the other hand, the networks placed at the inverter output follow the second one. In this last case, although the reflection phenomena exists the overvoltage does not appear because the voltage pulse rise time is somehow kept bigger than the voltage pulse traveling time.The design process through simulation and anal...

The feature size of the CMOS processes decreased during the past few years and problems such as reduced dynamic range have become more significant in voltage-mode pixels, even though the integration of more functionality inside the pixel has become easier. This work makes a contribution on both sides: the possibility of a high signal excursion range using current-mode circuits together with functionality addition by making signal amplification inside the pixel. The classic 3T pixel architecture was rebuild with small modifications to integrate a transconductance amplifier providing a current as an output. The matrix with these new pixels will operate as a whole large transistor outsourcing an amplified current that will be used for signal processing. This current is controlled by the intensity of the light received by the matrix, modulated pixel by pixel. The output current can be controlled by the biasing circuits to achieve a very large range of output signal levels. It can also be controlled with the matrix size and this permits a very high degree of freedom on the signal level, observing the current densities inside the integrated circuit. In addition, the matrix can operate at very small integration times. Its applications would be those in which fast imaging processing, high signal amplification are required and low resolution is not a major problem, such as UV image sensors. Simulation results will be presented to support: operation, control, design, signal excursion levels and linearity for a matrix of pixels that was conceived using this new concept of sensor.