三十年“顽症”一朝除——通州市供电局切除“转供电”为企业减负调查

切除“转供电”是许多企业普遍感到头痛的问题,年年喊切除,年年遇麻烦,年年切不掉。然而,作为江苏省首批农网改造36个竣工县之一的通州市供电局抓住这一契机,进行合理规划,配合强有力的措施。把这一30年的“顽症”攻克了。目前,已顺利切除114家,取得了令人鼓舞、前所未有的突破性进展…… 通州市工业经济一直较发达,尤其乡镇村工业发展迅猛。早在60、70年代这里就兴办国有、市属企业上百家,乡镇村办厂上千家。

Outage Performance of Cognitive DF Relaying Networks Employing SWIPT

In this paper, the outage perfor- mance of a cognitive relaying network over Nakagami-m fading channels, employing simultaneous wireless information and power transfer （SWIPT） technology is analyzed and evaluated. The operation of this network is considered in conjunction with the convention- al decode-and-forward （DF） and incremental DF （IDF） protocols. For the conventional DF protocol, it is assumed that there is no direct link between the secondary transmitter （S） and the secondary destination （D）, while （for both protocols） after harvesting energy, the relay node （R） always helps to forward the resulting signal to D. However, for the IDF protocol, R assists in relaying S＇s information to D only when the direct communication between S and D has failed. Furthermore, for both DF and IDF protocols, we assume there is no power supply for R, and R harvests energy from the transmitted signal of S. We derive exact ana- lytical expressions for the outage probability at D in DF and IDF protocols, respectively, in terms of the bivariate Meijer＇s G-function. Performance evaluation results obtained by means of Monte-Carlo simulations are also provided and have validated the correctness of the oroDosed analysis.

A new method to accurately measure the drift of shipborne floated gyro

Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hoist was constructed. The hydraulic pressure cylinder and the accumulator were analyzed and calculated. Finally, PRO/E and ADAMS were used to simulate the hoist and its hydraulic system. It was found that this type of virtuaU674.7l prototype provides a good method to actualize a physical prototype.

A new solar coupling regeneration method for liquid desiccant air-conditioning system

A new solar coupling regeneration system is proposed in order to improve the reliability of solar desiccant regeneration system.The new system makes comprehensively use of the solar energy and can also be appropriate for energy-storage in a night operation mode when the electric power supply is at its valley.Comparison of the performance of the new system,the solar thermal regeneration system and the solar electrodialysis regeneration system are made and the influential factors of the performance of the new system are investigated.The results reveal that the new system will be more energy efficient than the solar thermal regeneration system and the solar electrodialysis regeneration system.

Relevance of the P ＆ O MPPT Technique in an Original PV-Powered Water Pumping Application

Many papers exploiting the various MPPT （maximum power point tracking） techniques in PV （photovoltaic） applications, from the simple to the most complicated, can be found in literature. However, these techniques may not always be easy to implement in industrial applications. The main challenge of this paper is to model and implement the P ＆ O （perturb and observe） algorithm in a low-cost PV-powered pumping system. To that end, a comparative investigation of the performance characteristics of the most popular MPPT methods, such as FOCV （fractional open circuit voltage）, FSCC （fractional short circuit current）, FLC （fuzzy logic control）, ANN （artificial neural network） and INC （incremental conductance） is presented. This analysis is helpful to highlight the relevance of the P ＆ O technique taking better account of complexity, difficulty of implementation and cost considerations in water pumping applications. The targeted PV-powered pumping system is based on a single-phase induction motor supplied by a three-phase inverter controlled by the DTC （direct torque control） technique. This stand-alone PV system is dedicated to water pumping, especially in rural areas that have no access to national grids but have sufficient amount of solar radiation. Simulation modeling （Matlab/Simulink） and experimental results are presented to demonstrate the relevance of the system.

Energy and exergy performance investigation of transcritical CO_2-based Rankine cycle powered by solar energy

A comprehensive performance evaluation of a solar assisted transcritical CO2-based Rankine cycle system is made with exergy analysis method. The actual thermal data taken from the all-day experiment of the system are utilized to determine energy transfer and the exergy destructions in each component of the system. In addition, a hypothetical carbon dioxide expansion turbine is introduced, then two thermodynamic models for solar transcritical carbon dioxide Rankine cycles with a throttling valve (experiment) and with an expansion turbine have been established with exergy analysis method. The obtained results clearly show that solar collector contributes the largest share to system irreversibility and entropy generation in the all-day working state, and the exergy improvement potential of solar collector is the maximum in the working state. So this component should be the optimization design focus to improve system exergy effectiveness. For the cycle with the turbine, the energy efficiency and the entropy generation are not much higher than the cycle with throttling valve, but the exergy efficiency of the cycle with turbine is twice of the cycle with throttling valve. It provides more guidance when the transcritical CO2-based Rankine system is in a large-scale solar application.