Linear Control of a Nonlinear Power Take-Off Simulation for Wave Energy Conversion in Irregular Seas
This article discusses a control strategy for optimal energy capture in irregullar seas by focusing on control of the power take off (PTO) element of a point absorber wave energy converter.The research is based on a nonlinear simulation of a PTO hydraulic circuit,in which the piston velocity and generator torque act asdisturbance and control actuator variables respectively,whilst the damping force is the output variable under control.The piston velocity is generated by a hydrodynamic simulation model of a heaving buoy,acting with one degree of freedom,that reacts to both the damping force from the PTO simulation and the irregular sea wave profile.The damping force set point will be obtained from an associated power capture optimisation module and may be time varying.However,it is clear that such an adaptive tuning system also requires high performance low-level control of the device actuators,in order to fully realise the benefits of optimisation.In this regard,the present article illustrates use of the Proportional-Integral-Plus (PIP) control methodology applied to the PTO simulation.In their simplest linear form,such PIP controllers do not account for the interconnected system variables mentioned above. For this reason,the research also considers feed-forward and state-dependent forms of PIP control,in which the piston velocity is appended to a non-minimal state space representation of the system.
SUPERGEN power take off simulation optimal control non-minimal state space
M.A.Stables G.Aggidis C.J.Taylor P.Cross Kester Gunn
Engineering Department,Lancaster University,LA1 4YR,Lancaster,UK
国际会议
哈尔滨
英文
71-89
2009-09-17（万方平台首次上网日期，不代表论文的发表时间）