A Steady-State Errors Correction Method for Eliminating Measurement Errors

This paper proposes a steady-state errors correction(SSEC)method for eliminating measurement errors.This method is based on the detections of error signal E(s)and output C(s)which generate an expected output R(s).In comparison with the conventional solutions which are based on detecting the expected output R(s)and output C(s)to obtain error signal E(s),the measurement errors are eliminated even the error might be at a significant level.Moreover,it is possible that the individual debugging by regulating the coefficient K for every member of the multiple objectives achieves the optimization of the open loop gain.Therefore,this simple method can be applied to the weak coupling and multiple objectives system,which is usually controlled by complex controller.The principle of eliminating measurement errors is derived analytically,and the advantages comparing with the conventional solutions are depicted.Based on the SSEC method analysis,an application of this method for an active power filter(APF)is investigated and the effectiveness and viability of the scheme are demonstrated through the simulation and experimental verifications.

Impact of low temperature on smartphone battery consumption

Most smartphones employ Li-ion(or Li-polymer)batteries as their power sources.Though battery consumption significantly varies along with the cell temperature,which is severely affected by ambient temperature,many studies simply assume that the cell temperature is equal to room temperature.Furthermore,there has not been any study that has quantitatively analysed the impact of ambient temperature on battery consumption.In this paper,it can be shown that low ambient temperature significantly affects battery consumption of a smartphone.To show the impact of the cell temperature on battery consumption,the battery consumption at low ambient temperature(-20℃)is compared with that at room temperature.As a result,high power consumption results in more severe battery consumption at low ambient temperature.Real measurements show that the battery consumption increases by up to 113.1%at low ambient temperature in comparison with the same discharge condition at room temperature.

AC current automatic calibration using two different TCC designs

AC currents are automatically calibrated by two different thermal current converter(TCC)designs.The two designs are different in the used number of the thermal-elements(TEs).Consequently they differ in their output electro motive force(EMF).Studying the effect of changing the output EMF is done in this paper through calibrating AC currents.5 mA and 5 A are accurately calibrated at different frequencies 55 Hz,1 kHz and10 kHz by the two TCCs.A comparison is made between the results to evaluate the effect of the output EMF value on the accuracy and the uncertainty of the low and higher AC current calibration.A LabVIEW program is designed for this accurate automatic calibration to overcome the problems of the manual calibration on the thermal converters.