太阳能驱动喷灌机组行走动力和光伏功率匹配设计与试验

为明晰太阳能驱动喷灌机组动力匹配设计理论和方法,促进太阳能喷灌机组推广应用,解决能源短缺地区的灌溉动力问题.文章以课题组研发的太阳能驱动喷灌机组为平台,通过对机组工作方式和行走驱动理论进行分析,构建了一种太阳能驱动喷灌机组动力需求与光伏功率匹配设计方法.通过试验对机组行走驱动需求功率计算理论进行了验证,并以夏季典型晴天下机组累积最大工作时长和设计日标准工作时间为标准,分别从纵向和横向上对机组日工作能力和光伏系统供电性能进行了分析.结果表明:喷灌机组行走驱动功率实测值与理论计算值基本吻合,最大相对误差为7.3％,进一步验证了行走驱动功率理论计算的可靠性;夏季典型晴天下,机组累积最大工作时间随机组喷灌功率和运行速度减小而变长,以试验当天为例,当机组以最大设计流量、最大运行速度处于最大负荷工况下时,最大工作时间接近20 h,表明机组工作能力较强;以机组设计日8h工作时间为准,在2016年7月进行了为期一个月的光伏供电监测,从横向上对系统供电能力进行分析,结果显示在为期一个月的检测过程中系统总缺电时数8.75 h,占系统总供电时长的3.5％,表明光伏供电系统可靠性较高.该研究为实现太阳能与农业机械相结合、太阳能喷灌机组驱动系统方案设计与优化,促进太阳能驱动喷灌机组在实际工程中的推广应用,解决能源短缺地区灌溉动力问题提供了参考.

Design and test of driving power and photovoltaic power matching for solar-driven sprinkler irrigation unit

Abstract: The development of effective irrigation machine is one of the factors which can promote the development of agriculture and increasing crop yield. Facing the shortage of energy and limitation of water resources, the development of agricultural irrigation has been constrained. Removable sprinkler irrigation has been widely used due to its high automation, labor saving, and many other advantages. However, a stable power supply is needed, especially in some remote areas where the maximum electricity cannot be fully guaranteed. This may lead to water shortage for crops, and such areas usually cannot be timely irrigated. The solar-driven sprinkler unit can save energy and water. It is of great significance to improve the efficiency of farmland irrigation, reduce labor costs, and solve the problem of irrigation power in the areas where energy is in shortage. In order to improve irrigation efficiency, reduce labor cost, and solve the problem of irrigation power in those areas, the present research was carried out on the driving force demand and the photovoltaic power matching of the unit through the solar energy to drive sprinkler irrigation, which was developed by our research group. According to the characteristics of the unit structure and the driving power, a dynamic design and matching design method of the solar energy drive sprinkler unit were constructed by theoretical calculation of the power supply and demand of the unit. The calculated power of the driving demand was verified through experiments. The typical working hours and designed daily standard working hours of the typical sunny summer units were evaluated for the working capacity of the unit and the power supply capacity of the PV system. The results showed that the measured value of travel drive power was basically consistent with the theoretical calculated value, and the maximum relative error was 7.3%, indicating the reliability of the calculation of travel drive power. At the typical summer sunny day, the maximum cumulative working time of the unit increased with the decreases in irrigation power and running speed of the unit. Taking the tested day as an example, when the unit reached the maximum designed flow, the maximum operating speed was then in the maximum load condition and the maximum working time was about 20 hours, showing a stronger ability of the unit. A one-month PV power supply monitoring was conducted in Jul, 2016 on the basis of daily designed duration of 8 hours. And this made a study on power supply capacity through the horizontal of the system. The results showed that during the one-month detection process, the total systematic power shortage duration was about 8.75 hours, accounting for about 3.5% of the total power supply duration. This indicated that the photovoltaic power supply system had a high reliability. This study can provide references for realizing the combination of solar energy and agricultural machinery, designing and optimizing drive system of the solar-driven sprinkler unit, promoting the popularization and application of solar powered irrigation unit in engineering, and solving the problem of irrigation power shortage in the regions with less energy.