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To comprehensively meet the test requirements for the common mode rejection ratio (CMRR) across different ECG-particular standards, this paper presents the design of an ECG CMRR automatic test system. The hardware component primarily consists of a test signal generation module, an automatic control network (which includes a resistance-capacitance network control module and a polarization voltage control module), and a noise level switching module. The software portion enables automatic control and user interaction. Experimental results indicate that the system is stable, reliable, and highly automated, capable of satisfying the test requirements of various ECG-particular standards, thus demonstrating a promising application prospect.

Following a fault on an AC transmission line for new energy， the fault response of the new energy power supply can influence the operation of distance protection. Therefore， leveraging the control strategy of the new energy power supply， this study delves into alternations in impedance， system power angle， and faulty electrical quantity prior to and post-fault. It also contrasts the performance of three distance protection mechanisms： phase polarization voltage， positive-sequence polarization voltage， and sudden magnitude variation. Given that the phase voltage drops to zero when faults occur at the line outlet， a non-responsive zone is inherent in the action area of phase polarization voltage distance protection mechanism. After a fault， the phase of the positive sequence voltage is influenced by control and shifts. This presents risks of refusal to trip during an internal fault and false tripping during an external fault for positive-sequence polarization voltage phase-sequence distance protection mechanism. Regarding the sudden magnitude variation distance protection mechanism， a fault can compel a shift in the compensated voltage phase due to control influences， which could result in protection refusal or false tripping. Using the real-time digital simulator （RTDS）， a system model demonstrating the transmission of new energy via AC lines is established. A simulation analysis of the performance of the three mechanisms is performed. The findings from the simulation align seamlessly with the theoretical scrutiny.

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lithium plating is an important causation leading to capacity loss and thermal runaway of lithium-ion batteries. A detection method and alarm strategy of abnormal lithium plating can mitigate the risk form lithium plating. This paper presents a comprehensive and stable detection method for abnormal lithium plating based on variance entropy. An overvoltage-induced lithium plating experiment has been conduction on a 19-series lithium-ion battery pack, and the abnormal lithium plating was detected by the electrochemical characteristics and variance entropy. The variance entropy can analyze the subtle voltage inconsistencies of cells and first detect abnormal cells in Cycle 13. By comparing the electrochemical characteristics and variance entropy values, the effective application conditions of variance entropy were summarized. Moreover, the variance entropy and voltage platform were combined to extend the application condition and improve the stability. This research can provide the basis for the stable and robust detection method of abnormal lithium plating. • A pack-level detection method of abnormal lithium plating for LIBs is proposed. • Overvoltage cycling experiment for 19 series pack and analyze characteristics. • Variance entropy first time detecting abnormal lithium plating in Cycle 13. • Discover the effective conditions of the entropy detection for lithium plating. • Combining the variance entropy and the voltage platform to complementarity. [ABSTRACT FROM AUTHOR]

To comprehensively meet the test requirements for the common mode rejection ratio (CMRR) across different ECG-particular standards, this paper presents the design of an ECG CMRR automatic test system. The hardware component primarily consists of a test signal generation module, an automatic control network (which includes a resistance-capacitance network control module and a polarization voltage control module), and a noise level switching module. The software portion enables automatic control and user interaction. Experimental results indicate that the system is stable, reliable, and highly automated, capable of satisfying the test requirements of various ECG-particular standards, thus demonstrating a promising application prospect.

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An electrochemical-thermal Li-ion battery model considering electrochemical reactions and heat transfer was established. Firstly, polarization characteristics were analyzed in principle and polarization voltage was calculated. Then, cell voltage V and polarization voltage V versus SOC (state of charge) at different CC (constant-current) charging rates were discussed. Thirdly, average polarization P and cutoff SOC SOC were proposed to quantize the polarization level and its influence on charging under different charging conditions. Finally, influence factors on battery polarization including electrolyte salt concentration, electrolyte conductivity, active material particle radius, positive electrode conductivity, and ambient temperature were studied. In addition, influence of the factors on SOC and heat generation was investigated. The results show that polarization voltage has direct effect on cell voltage and is negatively related with charging performance and positively related with heat generation. Higher electrolyte salt concentration, positive electrode conductivity, lower electrode particle radius, and ambient temperature make for lower polarization voltage. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to develop direct current sources using BJT transistors on the linear region (active region). This region depends on the saturation voltage, maximum power and polarization voltage of the element; from these parameters it is obtained the load resistance range that ensures a constant current. The methodology is used to develop a DC current source prototype of 2A and the range of the load resistance is defined by the transistor characteristics. The temperature and power constrains are taking into account.

In order to optimize the control strategy of the lithium-ion battery, some experiments were carried out to get the laws of the variation of polarization voltage in the different SOC, the rate of charge and discharge, the method of charge and discharge and ambient temperatures. The results show that the polarization voltage varies smoothly and the battery can accept the high rate of charge and discharge as 10%soc<80%; the higher the rate of charge is, the more obvious polarization phenomenon is in the low and high SOC and the stability region is smaller; the cumulative phenomenon of polarization voltages are not the same in different temperature, the lower the temperature is, the more obvious polarization voltage changes; the cumulative phenomenon of polarization voltage is obvious, especially for LiMn2O4. [ABSTRACT FROM AUTHOR]

In this paper, two high-voltage charge pumps (CPs) are introduced. In order to minimize the area of the pumping capacitors, which dominates the overall area of the CP, high-density capacitors have been utilized. Nonetheless, these high-density capacitors suffer from low breakdown voltage, which is not compatible with the targeted high-voltage application. To circumvent the breakdown limitation, a special clocking scheme is used to limit the maximum voltage across any pumping capacitor. The two CP circuits were fabricated in a 0.6- \mu\m CMOS technology with poly0–poly1 capacitors. The output voltage of the two CPs reached 42.8 and 51 V, whereas the voltage across any capacitor did not exceed the value of the input voltage. Compared with other designs reported in the literature, the proposed CP provides the highest output voltage, which makes it more suitable for tuning MEMS devices. [ABSTRACT FROM PUBLISHER]

This paper presents a methodology to develop direct current sources using BJT transistors on the linear region (active region). This region depends on the saturation voltage, maximum power and polarization voltage of the element; from these parameters it is obtained the load resistance range that ensures a constant current. The methodology is used to develop a DC current source prototype of 2A and the range of the load resistance is defined by the transistor characteristics. The temperature and power constrains are taking into account. [ABSTRACT FROM AUTHOR]

Analytical model of the anode side of a direct methanol fuel cell is developed. The model takes into account non-Tafel kinetics of electrochemical reaction of methanol oxidation, diffusion transport of methanol through the backing layer and methanol crossover. General expression for the polarization voltage of the anode side is derived and simplified in a limits of small and large currents. Total limiting current density appears to be a combination of reaction- and diffusion-limiting current densities. The effect of methanol crossover on performance of the anode side is rationalized. [Copyright &y& Elsevier]

Based on exact solutions of the problem of catalyst layer performance, the fitting equation for voltage–current curve of a direct methanol fuel cell is derived. Voltage losses due to imperfect transport of reactants in the diffusion layers and due to methanol crossover are taken into account. The coefficients in fitting equation are expressed in terms of basic transport and kinetic parameters on both sides of the cell. Fitting of experimental voltage–current gives the estimate of these parameters. The formula for optimal methanol concentration is derived; with good accuracy it reproduces the experimental value. [Copyright &y& Elsevier]

An analytical solution to the problem of the performance of the cathode electrocatalyst layer in the polymer electrolyte fuel cell is obtained. This solution describes the effect of limiting current density due to imperfect oxygen transport in backing layer. Simple formulas for electrocatalyst layer polarization voltage are derived in the limiting cases of small and large currents. Based on exact formulas, the fitting equation for the polarization voltage is obtained. All fitting parameters are expressed in terms of transport and kinetic parameters. Comparison of theoretical and experimental voltage–current curves of a fuel cell shows reasonable agreement. The fitting equation furnishes an opportunity to characterize fuel cells using experimental voltage–current curves. [Copyright &y& Elsevier]

Performance of a catalyst layer of polymer electrolyte fuel cell under the assumptions of ideal transport of reactants and Tafel kinetics of electrochemical reaction is considered. Explicit expressions for the profiles of basic parameters (proton current density, overpotential and reaction rate) across the catalyst layer are obtained and a new conservation law is found. Exact expression for voltage–current curve of the catalyst layer is derived and simplified in the limiting cases of small and large current densities. The physics of transition from small to large currents is discussed. [Copyright &y& Elsevier]

From a total of 51 patients equipped with rate and pulse width adjustable pulse generators (Microlith-P 0505, Microthin-PI 05220) implanted over the last 3 years. 10(109.6%) showed an unexpected drop in pacemaker pulse rate during pulse width programming. For one of the pulse generators used (Microthin-PI 0522], unexpected rate decrease occurred in 7/13 cases (53.8%L). For all except one patient, decrease in pacemaker pulse rate corresponded with the total refractory period of the pulse generator ( 320 ms). at a certain pulse width when rate drop first occurred. In seven of the patients the pulse generator automatic interval was extended from 13 ms to 171 ms beyond the refractory period. In two patients it was necessary to replace the pulse generators. Our study strongly proves that this abnormal pacemaker functioning is a result of sensing of the polarization voltage at the pacemaker electrode/tissue interface and/or the T-wave. The polarization voltage is highly dependent on the total pacemaker electrode/tissue interface impedance. Using typical values for pulse generator output and input resistance and output capacitance, Faraday resistance, Helmholtz capacitance and tissue resistance at the electrode/tissue interface it was shown mathematically that in some cases the polarization voltage alone would be of sufficient amplitude and slew rate for pacemaker inhibition. The study demonstrates an urgent need for change in the filter characteristics by making the pulse generators less sensitive in the low frequency region and reducing the polarization voltage by reducing the output circuit capacitance. [ABSTRACT FROM AUTHOR]

A seven-year-old girl with a permanent epicardial programmable pulse generator developed inappropriate slowing of the pacing rate due to oversensing a combination of T wave and afterpotential voltage. This phenomenon occurred only in the first three days after implantation and was demonstrable only at long programmed pulse widths. Our observations suggest that the current of injury in the early post-operative period may generate a relatively high T wave voltage capable of combining with a large after potential to produce a signal exceeding the sensitivity of a demand pulse generator. [ABSTRACT FROM AUTHOR]