摘要
构建了一套可采集测量喷头喷雾压力数据的PWM变量喷雾实验平台,通过喷头压力与流量关系特性,经卡尔曼滤波算法得出喷雾瞬时流量数据,并对其积分得到喷雾流量。设计了一种自动分段线性拟合方法将滤波后得到的喷雾流量与PWM信号占空比相关联,最终建立PWM喷雾流量模型。在喷雾压力为0.2、0.3和0.4 MPa条件下,对各喷雾流量模型进行喷雾流量控制精度实验,实验表明3种压力条件下所建立的PWM喷雾流量模型决定系数R2均在0.995以上,喷雾流量控制误差在±6%范围内,说明该方法可以为快速、在线建立喷雾控制模型提供参考。
A platform was built up to collect the pressure data near the nozzle.The instantaneous flow data was calculated based on the relationship between pressure and flow by using Kalman filtering algorithm,and the average spray flow rate was obtained by integrating over the instantaneous flow,then an automatic piecewise linear fitting method was designed after considering the relationship between the duty cycle of PWM signal and the average spray flow rate.In order to verify the control effects of the spray flow rate model,the PWM spray flow rate models based on Kalman filtering were established under the spray pressure of 0.2,0.3 and 0.4MPa,respectively,and the experiments of spray flow rate control accuracy were performed under the same conditions.The results showed that the coefficient of determination（R^2） in the models above were all more than 0.995 under the three spray pressures,and the spray flow rate control error was within ± 6%.This method provides a reference of building spraying control model for rapid and online use.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2014年第10期60-65,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家高技术研究发展计划(863计划)资助项目(2012AA10A504)
农业部引进国际先进农业科学技术资助项目(2011-G32)
浙江省'新世纪151人才工程'资助项目
关键词
变量喷雾
脉宽调制
卡尔曼滤波
分段线性拟合
Variable spray Pulse width modulation Kalman filtering Piecewise linear fitting
