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摘要
在当今社会中，人们的生活水平不断提高，对食品安全问题尤为关注，食品的质量如何，新鲜程度如何，这些都成了人们关心的话题。水果和蔬菜是生活中重要的食物，它们含有丰富的营养物质，向人们提供碳水化合物、纤维素、无机盐、维他命和矿物质等，从而提高人们的健康水平。但由于新鲜食物本身的含水量高、易腐蚀的特性，以及相对分散的生产地和销售地，需要通过科学有效的保鲜技术，通过对微生物的有效抑制和对果蔬生理活动的调节，从而创造有利于果蔬保鲜的外部环境，达到减少果蔬腐烂、延缓果蔬成熟、保鲜的目的。既要保持果蔬当中的营养成分不要流失，还要保证新鲜程度，果蔬的保鲜便成为了现代家庭急待解决的问题。
此课题是一种基于PLC家庭果蔬保鲜智能控制设计。在本设计中，对放入保鲜箱中的水果蔬菜进行实时监测和控制，将温度、湿度、气体浓度、压力等参数控制在有利于储存果蔬保鲜的范围内。这一设计通过对果蔬保鲜箱进行温度、湿度、气体浓度、压力、通风调节控制的可编程控制器和人机界面的组态监测，实现了果蔬保鲜的安全储存，满足了现阶段家庭对果蔬保鲜的需求。
关键词：果蔬保鲜；PLC;自动控制
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ABSTRACT
Intodayssociety,peopleslivingstandardsareconstantlyimproving,andtheyareparticularlyconcernedaboutfoodsafetyissues,andthequalityandfreshnessoffoodhavebecometopicsofconcern.Amongthemanyfoods,fruitsandvegetablesareimportantfoodsinlife,theyarerichinnutrients,providingpeoplewithcarbohydrates,fiber,inorganicsalts,vitaminsandminerals,etc.,therebyimprovingpeopleshealth.However,duetothehighwatercontentandcorrosivecharacteristicsoffreshfooditself,aswellastherelativelyscatteredproductionandsalesplaces,itisnecessarytocreateanexternalenvironmentconducivetothepreservationoffruitsandvegetablesthroughscientificandeffectivepreservationtechnology,throughtheeffectiveinhibitionofmicroorganismsandtheregulationofphysiologicalactivitiesoffruitsandvegetables,soastoreducetherotoffruitsandvegetablesanddelaytheripeningandpreservationoffruitsandvegetables.Thepreservationoffruitsandvegetableshasbecomeamajorproblemthatmodernfamiliesurgentlyneedtosolve,notonlytokeepthenutrientsinfruitsandvegetablesfrombeinglost,butalsotoensurefreshness.
ThistopicisaPLC-basedintelligentcontroldesignforhomefruitandvegetablepreservation.
Inthisdesign,thefruitsandvegetablesplacedinthefresh-keepingboxaremonitoredandcontrolledinrealtime,andtheparameterssuchaste