为了提高重型汽车电控机械式自动变速器起步控制的平顺性,在对接合点前后加速度变化的分析基础上.提出了采用变结构串级双环控制维持发动机转速恒定的起步控制算法.针对离合器操纵系统的非线性特性,加速度环采用单神经元自适应PID(Propo...为了提高重型汽车电控机械式自动变速器起步控制的平顺性,在对接合点前后加速度变化的分析基础上.提出了采用变结构串级双环控制维持发动机转速恒定的起步控制算法.针对离合器操纵系统的非线性特性,加速度环采用单神经元自适应PID(Proportional Integral Differential)控制算法来解决非线性控制问题.实验结果表明采用该算法可有效抑制接合点前后的加速度,从而提高起步过程的性能.展开更多
独立光储发电系统不与大电网连接,仅靠系统控制策略保障电能质量,目前仍具有电能质量较差、系统不稳定的问题。以提高系统电能质量、增强系统稳定性为目的,提出一种基于稳压控制的控制策略。对于储能系统,在通过逆变器前首先进行稳压控...独立光储发电系统不与大电网连接,仅靠系统控制策略保障电能质量,目前仍具有电能质量较差、系统不稳定的问题。以提高系统电能质量、增强系统稳定性为目的,提出一种基于稳压控制的控制策略。对于储能系统,在通过逆变器前首先进行稳压控制,再通过逆变器的双环控制结构维持系统的电压与频率恒定。光伏电池在逆变器前采取最大功率点跟踪(Maximum Power Point Tracking,MPPT)及稳压控制,并采用空间矢量脉宽调制(Space Vector Pulse Width Modulation,SVPWM)的恒功率控制策略(PQ control)维持稳定输出。在Matlab/simulink环境下进行仿真测试,验证控制策略的有效性。展开更多
An all-digital hybrid current regulation scheme for the single-phase shunt active power filter （APF） is presented. The proposed hybrid current control scheme integrates the deadbeat control and the dual-mode structu...An all-digital hybrid current regulation scheme for the single-phase shunt active power filter （APF） is presented. The proposed hybrid current control scheme integrates the deadbeat control and the dual-mode structure repetitive control （DMRC） so that it can offer superior steady-state performance and good transient features. Unlike the conventional schemes, the proposed scheme-based APF can compensate both the odd and the even order harmonics in grid. The detailed design criteria and the stability analysis of the proposed hybrid current controller are presented. Moreover, an improved structure which incorporates the proposed hybrid controller and the resonant controller for tracking specific order harmonics is given. The relationships between the resonant controller and different repetitive control schemes are discussed. Experimental results verify the effectiveness and advantages of the proposed hybrid control scheme.展开更多
A circuit configuration and a circuit topologic family of the novel forward mode AC/AC converters with high frequency link are presented. The circuit configuration is constituted of input cycloconverter, high frequenc...A circuit configuration and a circuit topologic family of the novel forward mode AC/AC converters with high frequency link are presented. The circuit configuration is constituted of input cycloconverter, high frequency transformer, output cycloconverter, input and output filters. The circuit topologic family includes eight circuit topologies, such as full-bridge-full-wave mode, etc. The bi-polarity phase-shifted control strategy and steady principles are thoroughly investigated. The output characteristics are obtained. By using the bi-polarity phase-shifted control strategy with phase-shifted control between the output cycloconveter and the input cycloconverter, commutation overlap period of the output cycloconverter, and polarity selection of the output filtering inductance current and the input voltage, the leakage inductance energy and the output filtering inductance current are naturally commutated, and surge voltage and surge current of the cycloconverters are overcome. The converters have such advantages as simple topology, two-stage power conversions(LFAC/HFAC/LFAC), bi-directional power flow, high frequency electrical isolation, good output waveforms, and strong ability to stabilize voltage. The converters lay key technical foundation on a new-type of regulated sinusoidal AC power supplies and electronic transformers. The correction and advancement of the converters are well verified by a principle test.展开更多
Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing thr...Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing through to selectively guarantee the breakage of a double bond while leaving other two bonds as （Z,Z）. The products were diagnosed by using NMR spectrum, infrared （IR） and mass spectrometer techniques. It is concluded that these products could widely be used in the synthesis of insect pheromones instead of insecticides and as useful intermediate compounds in many chemical reactions.展开更多
文摘为了提高重型汽车电控机械式自动变速器起步控制的平顺性,在对接合点前后加速度变化的分析基础上.提出了采用变结构串级双环控制维持发动机转速恒定的起步控制算法.针对离合器操纵系统的非线性特性,加速度环采用单神经元自适应PID(Proportional Integral Differential)控制算法来解决非线性控制问题.实验结果表明采用该算法可有效抑制接合点前后的加速度,从而提高起步过程的性能.
文摘独立光储发电系统不与大电网连接,仅靠系统控制策略保障电能质量,目前仍具有电能质量较差、系统不稳定的问题。以提高系统电能质量、增强系统稳定性为目的,提出一种基于稳压控制的控制策略。对于储能系统,在通过逆变器前首先进行稳压控制,再通过逆变器的双环控制结构维持系统的电压与频率恒定。光伏电池在逆变器前采取最大功率点跟踪(Maximum Power Point Tracking,MPPT)及稳压控制,并采用空间矢量脉宽调制(Space Vector Pulse Width Modulation,SVPWM)的恒功率控制策略(PQ control)维持稳定输出。在Matlab/simulink环境下进行仿真测试,验证控制策略的有效性。
基金The National Basic Research Program of China(973 Program)(No.2013CB035603)the National Natural Science Foundation of China(No.51007008,51137001)+1 种基金the Ph.D.Programs Foundation of Ministry of Education of China(No.20100092120043)the Fundamental Research Funds for the Central Universities
文摘An all-digital hybrid current regulation scheme for the single-phase shunt active power filter （APF） is presented. The proposed hybrid current control scheme integrates the deadbeat control and the dual-mode structure repetitive control （DMRC） so that it can offer superior steady-state performance and good transient features. Unlike the conventional schemes, the proposed scheme-based APF can compensate both the odd and the even order harmonics in grid. The detailed design criteria and the stability analysis of the proposed hybrid current controller are presented. Moreover, an improved structure which incorporates the proposed hybrid controller and the resonant controller for tracking specific order harmonics is given. The relationships between the resonant controller and different repetitive control schemes are discussed. Experimental results verify the effectiveness and advantages of the proposed hybrid control scheme.
文摘A circuit configuration and a circuit topologic family of the novel forward mode AC/AC converters with high frequency link are presented. The circuit configuration is constituted of input cycloconverter, high frequency transformer, output cycloconverter, input and output filters. The circuit topologic family includes eight circuit topologies, such as full-bridge-full-wave mode, etc. The bi-polarity phase-shifted control strategy and steady principles are thoroughly investigated. The output characteristics are obtained. By using the bi-polarity phase-shifted control strategy with phase-shifted control between the output cycloconveter and the input cycloconverter, commutation overlap period of the output cycloconverter, and polarity selection of the output filtering inductance current and the input voltage, the leakage inductance energy and the output filtering inductance current are naturally commutated, and surge voltage and surge current of the cycloconverters are overcome. The converters have such advantages as simple topology, two-stage power conversions(LFAC/HFAC/LFAC), bi-directional power flow, high frequency electrical isolation, good output waveforms, and strong ability to stabilize voltage. The converters lay key technical foundation on a new-type of regulated sinusoidal AC power supplies and electronic transformers. The correction and advancement of the converters are well verified by a principle test.
文摘Some unsaturated compounds with the required （Z,Z）-double bonds configuration are synthesized through controlled ozonolysis process of 1,5,9-cyclododecatriene by determining the necessary amount of ozone passing through to selectively guarantee the breakage of a double bond while leaving other two bonds as （Z,Z）. The products were diagnosed by using NMR spectrum, infrared （IR） and mass spectrometer techniques. It is concluded that these products could widely be used in the synthesis of insect pheromones instead of insecticides and as useful intermediate compounds in many chemical reactions.
