Liqiang Yuan

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DC voltage control is critical for grid-connected inverters, as it contributes to reduce the DC capacitance and improve system reliability as well as MPPT performance. A predictive control scheme of DC voltage for single-stage three-phase grid-connected PV inverters is proposed based on the analysis of the energy balance relationship in one control period,(More)
Separated longitudinal and transverse cross sections for charged pion electroproduction from 1 H, 2 H, and 3 He were measured at Q 2 ෇ 0.4 ͑GeV͞c͒ 2 for two values of the invariant mass, W ෇ 1.15 GeV and W ෇ 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta(More)
The ratio of longitudinal to transverse electron scattering oo the proton is a fundamental quantity that should bemeasured with the bestpossible accuracy. Measurements have been made to extract the ratio R = L == T from deep inelastic cross sections measured at momentum transfers as high as Q 2 = 50 (GeV/c) 2. The small values of R measured in deep(More)
GARBOW EDUCATION/TRAINING (Begin with baccalaureate or other initial professional education, such as nursing, include postdoctoral training and residency training if applicable.) INSTITUTION AND LOCATION DEGREE (if applicable) Radiology's Biomedical Magnetic Resonance Laboratory (BMRL). With more than 30 years of experience in magnetic resonance imaging and(More)
—This paper proposed an enhanced dc preexcitation for a variable-voltage variable-frequency-controlled induction motor drive system. Voltage vectors were adjusted according to the reac-tive component of the motor current, which promptly established the effective value of the motor flux linkage at the preexcitation stage and restrained its trajectory(More)
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Energy resources and their utilization intimately relate to sustainable development. In attaining sustainable development, increasing the energy efficiencies of processes utilizing sustainable energy resources plays an important role. The utilization of renewable energy offers a wide range of exceptional benefits. In this paper an attempt has been made to(More)