Applied Mechanics and Materials Vols. 672-674

Abstract: As coal, oil, natural gas and other non-renewable energy consumption and increasing energy demand, the utilization of solar energy as a new energy is greatly enhanced. In this work, a grid connected photovoltaic solar air conditioning system is designed, mainly comprised of solar panel, controller, inverter, room air conditioner and other parts. Air conditioning systems rely mainly on solar photovoltaic power; achieve the effect of energy conservation and environmental protection. The experimental result indicates that the system can achieve stable operation and the utilization of solar energy driving air conditioning system to save electricity. This air conditioning system is compared with the ordinary air conditioning system, SEER can increase 10.6 ~ 29.4%, HSPF can increase 6.25 ~ 18.5%.

Abstract: The current situation, domestic supportive policies and problems of photovoltaic generation technology are analyzed. According to the roof resources and solar illumination conditions in Shanghai, feasibility analysis of distributed roof photovoltaic generation technology is presented in angle of economic feasibility. The influence of generation price subsidies on the internal rate of return and payback period is obtained and finally raising advices to improve domestic photovoltaic generation technology.

Abstract: Microgrids are LV or MV electric networks which utilize various distributed generators (DG)to serve local loads. They could operate in either grid-connected or island mode, and hence increase the reliability of energy supplies. In this paper, dynamic models of photovoltaic cell were described in ElectroMagnetic Transient Program/Alternative Transients Program(EMTP/ATP).In addition, basic models of the equivalent power electronic interfaces and batteries were developed.The above models have been integrated in a microgrid to represent the dynamic characteristic of steady state and transient operation. When operated under steady state, the PV cells could be able to deliver power supply to the load via electronic interfaces. When fault,the battery with P/V and Q/f control strategy based on the droop characteristics was developed to isolate the microgrid from the main grid in a rapid and seamless way,which contributing effective control of voltage and enhancement of system stability. Simulation results verify the feasibility of the proposed models.

Abstract: With the development of national fitness activities, stadiums with all kinds of standards are established across the country. The functions of illumination and refrigeration inside stadiums have applied electricity. In order to save the consumption of energy, keep the sustainable development of society, as well as reinforce the consciousness of environmental protection, the thesis designs a set of novel light guided automatic lighting system of solar energy. The system realizes indoor illumination with controlling system. In the daytime, the system uses optical materials with automatic following lighting for indoor illumination, while uses stored energy of storage battery provided by daytime solar panel for LED illumination. The solar cell also provides energy for daytime automatic following lighting device. This device can take full advantage of solar energy to deal with the problem of energy waste, as well as proposes a new idea for energy conservation and emission reduction for stadiums.

Abstract: As an indispensable part of renewable energy power generation system, energy storage to a large extent, has resolved randomness and fluctuation of photovoltaic power generation and enabled its smooth output. Firstly, a method of energy management by means of LabVIEW was proposed. Based on its advantages on data collection and convenience of hardware integration application, this software was used to conduct real-time surveillance and control of such parameters as charge-discharge current and DC line voltage. Then, five operating mode were raised on the basis of generating capacity of photovoltaic cell and surplus capacity of energy storage battery , insure quick response and high-efficiency operation of the system. Finally, the effectiveness of energy management proposed method was verified on the built experimental platform.

Abstract: This paper mainly discussed the control strategy of PV-energy storage microgrid that run in islanded mode , the PV inverter and the energy storage inverter use constant power control and constant voltage and constant frequency control respectively,with such a control strategy to ensure the microgrid in islanded mode supply the load stably. To verify the proposed theory,built the simulation model on the Simulink platform.In order to facilitate the parameters modification and improve the speed of the simulation,PQ controller was programmed by C language and embedded in the Simulink platform.Through the analysis of the simulation results,proved that the correctness and validity of the control strategy.

Abstract: Due to serious environmental problems and energy supply and demand issues, solar energy as a clean and abundant energy gets more and more attention. This paper presented a novel cooling and power system combined with PTCs. The system performance analysis was conducted with four different organic working fluids. The impacts of organic Rankine cycle (ORC) evaporation temperature, ORC condensing temperature and heat transfer fluid (HTF) mass flow rate in evaporator on system thermal performance were analyzed. The results show that system with toluene as working fluid has the highest thermal and exergy efficiency, and D4 and MDM have the lowest. Different working fluids have different cooling power to electricity ratios. The HTF mass flow rate in evaporator has a significant effect on system thermal performance.

Abstract: For the capacity and the location of the photovoltaic power generation in the urban distribution network, this paper adopts LSI(Loss sensitivity index) to determine the access to the location of photovoltaic power generation system. At the same time, we put forward a kind of multi-objective programming methods for the distribution network, which adopts three sorts of indices including LOI(Loss optimization index), EOI(Environmental optimization index) and VQI (Voltage quality index) as a multi-objective function. Therefore, an auxiliary search space is built in this paper to improve BPSO(binary particle swarm algorithm), in order to solve the complicated nonlinear optimization problem. And through the simulation verification IEEE-30, the simulation results show that this method can realize the optimization of distribution network system configuration.

Abstract: Humidification-dehumidification (HDH) desalination is one of the most promising small-scale desalination technologies as the process is simple and fits decentralized water production, moreover, the device runs steady and needs low maintenance. In this paper, the basic theory of the HDH system is introduced and many different studies on the HDH technology are also reviewed. The research aspects such as solar collector, humidifier, multi-effect system, the optimum flow rate ratio of water to air and the systems of multiple extractions and injections are compared and summarized. At last, future development has been point out to improve the overall usability.

Abstract: Solar tracker is an important part of photovoltaic generation and solar heating system. By solar tracker, the efficiency of solar utility can be significantly improved. Considering the camera device is widely applied in the photovoltaic generation and solar heating systems, based on the visual motoring equipment, a kind of solar tracker is designed. Using the proposed solar tracker, the height and the angle of the sun can be detected and be applied in solar tracker controller. Experiments show this design has relatively high accurate rate during a week’s period while the weather are partly cloudy or clear. It shows good application future in photovoltaic generation and solar heating industries.