Abstract:

To solve the problem that the variable load torque with large amplitude and high frequency imposed on the sun pointing device by the large flexibility and large inertia characteristics of the solar panels, it is difficult to simulate and the simulation accuracy is not enough. A ground semi-physical simulation test system is designed with the electric load simulator as the core device. First, the mechanism model of the motor driven load simulator (loading unit) is established. The parameters of the loading unit is identified by the recursive least square method with the influence of each parameter on the response characteristics of the loading unit is analyzed. A composite control algorithm combining the lead compensation with the fuzzy adaptive PID is proposed to the loading unit controller design. This effectively broadens the bandwidth of the loading unit with the improved torque following performance and the suppressed torque error. The response speed, loading bandwidth and loading accuracy of the test system are analyzed and evaluated by the different signals input. The experimental results show that the composite control algorithm makes the loading torque well realized the desire output torque of the solar panel model. The accurate loading (test) torque of the desire model is simulated for the driving performance evaluation exeperiment of the sun pointing device to the solar panels.

Key words: Sun pointing device, Semi physical simulation, Motor driven load simulator, Compound control, Least square method