During the flight of tethered unmanned aerial vehicle (UAV)

the cable acts a varying tension on the UAV

which usually causes the crash of UAV in serious cases. Therefore

the influence of cable tension must be considered in the design of tethered UAV control algorithm. In this research

the cable tension is approximately proportional to the flight height of the UAV

the simplified six degree of freedom mathematical model of the tethered quadrotor UAV is established

the cascade PID controller is designed for simulation analysis and the tethered quadrotor UAV model test system is built for experimental testing in the breeze environment. The results show that the cascade PID controller designed can make the tethered UAV achieve good flight effect in the breeze environment

the cable tension acted on the tethered UAV platform is mainly related to the flight height of the UAV

so the treatment method of cable tension is feasible.