We propose an optimal stochastic scheduling strategy for a multi-vector energy complex(MEC),considering a fullblown model of the power-to-biomethane(Pt M)process.Unlike conventional optimization that uses a simple eff...We propose an optimal stochastic scheduling strategy for a multi-vector energy complex(MEC),considering a fullblown model of the power-to-biomethane(Pt M)process.Unlike conventional optimization that uses a simple efficiency coefficient to coarsely model energy conversion between electricity and biomethane,a detailed Pt M model is introduced to emphasize the reactor kinetics and chemical equilibria of methanation.This model crystallizes the interactions between the Pt M process and MEC flexibility,allowing to adjust the operating condition of the methanation reactor for optimal MEC operation in stochastic scenarios.Temperature optimization and flowsheet design of the Pt M process increase the average selectivity of methane(i.e.,ratio between net biomethane production and hydrogen consumption)up to 83.7%in the proposed synthesis flowsheet.Simulation results can provide information and predictions to operators about the optimal operating conditions of a Pt M unit while improving the MEC flexibility.展开更多
三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model ...三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model predictive control, MVMPC)策略。针对三相四开关整流器无零矢量问题,建立等效零矢量模型;为保证直流电压的稳定,采用参考功率补偿策略来平衡直流侧电容电压;多矢量模型预测控制方面,每个采样周期选取两个基本电压矢量和一个等效零矢量,这使得等效合成矢量方向幅值均可调,扩大了等效合成矢量的作用范围,提高了系统的控制精度。仿真结果表明,电容均压多矢量模型预测控制策略能使三相四开关整流器可靠稳定地运行,对功率、网侧电流、直流侧电容电压等有着良好的控制效果;与传统的模型预测控制策略(conventional model predictive control, CMPC)相比,所提控制策略具有更小的功率脉动以及更低的电流谐波含量,且开关频率恒定,谐波电流分布规律。展开更多
针对传统矢量定姿方法精度较低的问题,研究了主流的星敏感器多矢量天文定姿算法,从理论上对奇异值分解(singular value decomposition,SVD)算法、双矢量定姿加研究背景算法、最小二乘(least square,LS)算法、四元数估计(quaternion esti...针对传统矢量定姿方法精度较低的问题,研究了主流的星敏感器多矢量天文定姿算法,从理论上对奇异值分解(singular value decomposition,SVD)算法、双矢量定姿加研究背景算法、最小二乘(least square,LS)算法、四元数估计(quaternion estimator,QUEST)算法和线性估计算法进行了详细推导。其中,线性估计算法先将各矢量对的坐标变换等式分散表示,推导出对应的四元数形式,再联立所有矢量的坐标变换等式,基于长方矩阵的Moore-Penrose伪逆运算对二次四元数矩阵方程线性化,再在此基础上考虑随机噪声的影响对一次四元数矩阵方程进行鲁棒性操作,具有良好的创新性与实用性。以最小化Wahba损失函数为目标,对定姿算法的性能进行对比分析。仿真和实验结果表明,线性估计算法较之于其余4种算法,具有更快的解算速度、更高的定姿精度。展开更多
Based on the SinoMOS 1 μm 40 V CMOS process, a novel power factor corrention （PFC） converter with a low-power variable frequency function is presented. The circuit introduces a multi-vector error amplifier and a pr...Based on the SinoMOS 1 μm 40 V CMOS process, a novel power factor corrention （PFC） converter with a low-power variable frequency function is presented. The circuit introduces a multi-vector error amplifier and a programmable oscillator to achieve frequency modulation, which provides a rapid dynamic response and precise output voltage clamping with low power in the entire load. According to the external load variation, the system can modulate the circuit operating frequency linearly, thereby ensuring that the PFC converter can work in frequency conversionmode. Measured results show that the normal operating frequency of the PFC converter is 5-6 kHz, the start-up current is 36 μA, the stable operating current is only 2.43 mA, the efficiency is 97.3%, the power factor （PF） is 0.988, THD is 3.8%, the load adjust rate is 3%, and the linear adjust rate is less than 1%. Both theoretical and practical results reveal that the power consumption of the whole supply system is reduced efficiently, especially when the load varies. The active die area of the PFC converter chip is 1.61 ×1.52 mm^2.展开更多
基金supported by the National Key R&D Program of China“Large-scale energy storage systems based on high temperature solid oxide electrolysis cells and biogas methanation technologies”(No.2021YFE0191200)。
文摘We propose an optimal stochastic scheduling strategy for a multi-vector energy complex(MEC),considering a fullblown model of the power-to-biomethane(Pt M)process.Unlike conventional optimization that uses a simple efficiency coefficient to coarsely model energy conversion between electricity and biomethane,a detailed Pt M model is introduced to emphasize the reactor kinetics and chemical equilibria of methanation.This model crystallizes the interactions between the Pt M process and MEC flexibility,allowing to adjust the operating condition of the methanation reactor for optimal MEC operation in stochastic scenarios.Temperature optimization and flowsheet design of the Pt M process increase the average selectivity of methane(i.e.,ratio between net biomethane production and hydrogen consumption)up to 83.7%in the proposed synthesis flowsheet.Simulation results can provide information and predictions to operators about the optimal operating conditions of a Pt M unit while improving the MEC flexibility.
文摘三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model predictive control, MVMPC)策略。针对三相四开关整流器无零矢量问题,建立等效零矢量模型;为保证直流电压的稳定,采用参考功率补偿策略来平衡直流侧电容电压;多矢量模型预测控制方面,每个采样周期选取两个基本电压矢量和一个等效零矢量,这使得等效合成矢量方向幅值均可调,扩大了等效合成矢量的作用范围,提高了系统的控制精度。仿真结果表明,电容均压多矢量模型预测控制策略能使三相四开关整流器可靠稳定地运行,对功率、网侧电流、直流侧电容电压等有着良好的控制效果;与传统的模型预测控制策略(conventional model predictive control, CMPC)相比,所提控制策略具有更小的功率脉动以及更低的电流谐波含量,且开关频率恒定,谐波电流分布规律。
文摘针对传统矢量定姿方法精度较低的问题,研究了主流的星敏感器多矢量天文定姿算法,从理论上对奇异值分解(singular value decomposition,SVD)算法、双矢量定姿加研究背景算法、最小二乘(least square,LS)算法、四元数估计(quaternion estimator,QUEST)算法和线性估计算法进行了详细推导。其中,线性估计算法先将各矢量对的坐标变换等式分散表示,推导出对应的四元数形式,再联立所有矢量的坐标变换等式,基于长方矩阵的Moore-Penrose伪逆运算对二次四元数矩阵方程线性化,再在此基础上考虑随机噪声的影响对一次四元数矩阵方程进行鲁棒性操作,具有良好的创新性与实用性。以最小化Wahba损失函数为目标,对定姿算法的性能进行对比分析。仿真和实验结果表明,线性估计算法较之于其余4种算法,具有更快的解算速度、更高的定姿精度。
基金supported by the National Natural Science Foundation of China(Nos.60676009,60776034)the Doctoral Foundation of Ministry of Education of China(No.20050701015)the National Outstanding Young Scientist Foundation of China(No.60725415).
文摘Based on the SinoMOS 1 μm 40 V CMOS process, a novel power factor corrention （PFC） converter with a low-power variable frequency function is presented. The circuit introduces a multi-vector error amplifier and a programmable oscillator to achieve frequency modulation, which provides a rapid dynamic response and precise output voltage clamping with low power in the entire load. According to the external load variation, the system can modulate the circuit operating frequency linearly, thereby ensuring that the PFC converter can work in frequency conversionmode. Measured results show that the normal operating frequency of the PFC converter is 5-6 kHz, the start-up current is 36 μA, the stable operating current is only 2.43 mA, the efficiency is 97.3%, the power factor （PF） is 0.988, THD is 3.8%, the load adjust rate is 3%, and the linear adjust rate is less than 1%. Both theoretical and practical results reveal that the power consumption of the whole supply system is reduced efficiently, especially when the load varies. The active die area of the PFC converter chip is 1.61 ×1.52 mm^2.
基金国家高技术研究发展计划(863)(the National High- Tech Research and Development Plan of China under Grant No.2006AA01Z148)教育部科学技术研究重点项目(the Scientific Key Project of Ministry of Education of China under Grant No.207148)
