电动固旋翼无人机动力系统建模与优化设计

为解决电动固定翼四旋翼复合布局无人机(eHAV)动力系统设计选择缺乏相应理论方法的问题,提出了一套动力系统的建模和优化设计方法。通过推质比计算提出了动力系统需求,利用螺旋桨和旋翼理论建立了螺旋桨的设计和性能计算模型,通过统计分析和1阶电动机模型建立了无刷直流电动机的计算模型,通过电动机与电池电压、电流之间的关系建立了电池选择方法,在经过电压修正的放电特性经验公式基础上建立了无人机航时计算方法。根据动力系统匹配方法,建立了动力系统优化设计流程。对某电动固旋翼无人机动力系统进行了优化设计和选择,结果表明:所建螺旋桨和旋翼模型计算结果与CFD结果的误差在10%以内,电池放电模型与试验数据的拟合度在0.97以上,飞行测试结果表明所提方法选择的动力系统使得无人机航时测试值与设计值误差小于4%,证明了该方法有较高的准确性和可行性。 

Modeling and optimal design of power system for electric fixed-wing quadrotor hybrid unmanned aerial vehicle

A modeling and optimal design method of power system was proposed to solve the problem of lack in theoretical method for power system design and selection of electric fixed-wing quadrotor hybrid unmanned aerial vehicle (eHAV). The need of power system was proposed by calculating the thrust-to-mass ratio. The models of propeller design and performance calculation were established using propeller and rotor theories. The brushless permanent magnet DC electric motor was modeled using statistic method and first order motor model. The relations of voltage and current between motor and battery were used to establish the battery selection method. A fully empirical model for battery discharge characteristics with voltage correction was used to calculate the endurance of eHAV. The optimal design flow of power system was established based on the matching method. The power system of an eHAV was optimized and selected. The results showed that the errors between the proposed rotor and propeller models and CFD method were less than 10%, and the fitting degree between the discharge model and the experimental data was greater than 0.97. The flight test showed that the error of endurance between the flight test result and the design value was less than 4%, verifying the correction and feasibility of the method of power system modeling and optimal design.