The successive approximation register(SAR)is one of the most energy-efficient analog-to-digital converter(ADC)architecture for medium-resolution applications.However,its high energy efficiency quickly diminishes when ...The successive approximation register(SAR)is one of the most energy-efficient analog-to-digital converter(ADC)architecture for medium-resolution applications.However,its high energy efficiency quickly diminishes when the target resolution increases.This is because a SAR ADC suffers from several major error source,including the sampling kT/C noise,the comparator noise,and the DAC mismatch.These errors are increasing hard to address in high-resolution SAR ADCs.This paper reviews recent advances on error suppression techniques for SAR ADCs,including the sampling kT/C noise reduction,the noise-shaping(NS)SAR,and the mismatch error shaping(MES).These techniques aim to boost the resolution of SAR ADCs while maintaining their superior energy efficiency.展开更多
This paper attempts at an in-depth exploration of lexical mismatching, a pattern of vocabulary errors. In this paper, errors per se were collected from 107 writing samples of Chinese college students, and then investi...This paper attempts at an in-depth exploration of lexical mismatching, a pattern of vocabulary errors. In this paper, errors per se were collected from 107 writing samples of Chinese college students, and then investigated from a variety of linguistic perspectives. Traditional theoretical approaches, i.e. CA and EA, are incorporated in the source analysis for a more comprehensive interpretation. Hopefully, the findings of the study will shed lights on lexical instruction and acquisition in the field of SLA.展开更多
永磁同步电机电流环控制性能是决定驱动系统性能的核心因素。电流预测控制能够使永磁同步电机电流控制获得良好的动态响应,但是控制器电机模型参数与实际电机参数不一致会引起电流静差,导致系统效率降低,无法输出额定转矩,以及无法工作...永磁同步电机电流环控制性能是决定驱动系统性能的核心因素。电流预测控制能够使永磁同步电机电流控制获得良好的动态响应,但是控制器电机模型参数与实际电机参数不一致会引起电流静差,导致系统效率降低,无法输出额定转矩,以及无法工作在力矩控制模式等问题。该文根据永磁同步电机预测控制模型,详细分析了控制器电机模型参数误差对电流控制的影响,并提出了一种静差消除算法。这种方法主要适用于控制器中电机模型电感及磁链参数不准的情况,通过在d轴电流控制中加入误差积分作用,并根据q轴电流的响应,动态调整控制器电机模型磁链参数,消除了控制器电机模型参数不准引起的静差。通过仿真分析和在3.3 k W永磁同步电机驱动平台上的实验,验证了该算法的有效性。展开更多
基金supported by National Natural Science Foundation of China(No.61904094,No.61934009)China Postdoctoral Science Foundation(No.2020M670329)Beijing Innovation Center for Future Chips(ICFC).
文摘The successive approximation register(SAR)is one of the most energy-efficient analog-to-digital converter(ADC)architecture for medium-resolution applications.However,its high energy efficiency quickly diminishes when the target resolution increases.This is because a SAR ADC suffers from several major error source,including the sampling kT/C noise,the comparator noise,and the DAC mismatch.These errors are increasing hard to address in high-resolution SAR ADCs.This paper reviews recent advances on error suppression techniques for SAR ADCs,including the sampling kT/C noise reduction,the noise-shaping(NS)SAR,and the mismatch error shaping(MES).These techniques aim to boost the resolution of SAR ADCs while maintaining their superior energy efficiency.
文摘This paper attempts at an in-depth exploration of lexical mismatching, a pattern of vocabulary errors. In this paper, errors per se were collected from 107 writing samples of Chinese college students, and then investigated from a variety of linguistic perspectives. Traditional theoretical approaches, i.e. CA and EA, are incorporated in the source analysis for a more comprehensive interpretation. Hopefully, the findings of the study will shed lights on lexical instruction and acquisition in the field of SLA.
文摘永磁同步电机电流环控制性能是决定驱动系统性能的核心因素。电流预测控制能够使永磁同步电机电流控制获得良好的动态响应,但是控制器电机模型参数与实际电机参数不一致会引起电流静差,导致系统效率降低,无法输出额定转矩,以及无法工作在力矩控制模式等问题。该文根据永磁同步电机预测控制模型,详细分析了控制器电机模型参数误差对电流控制的影响,并提出了一种静差消除算法。这种方法主要适用于控制器中电机模型电感及磁链参数不准的情况,通过在d轴电流控制中加入误差积分作用,并根据q轴电流的响应,动态调整控制器电机模型磁链参数,消除了控制器电机模型参数不准引起的静差。通过仿真分析和在3.3 k W永磁同步电机驱动平台上的实验,验证了该算法的有效性。
