Performance Analysis of Linear Quadratic Regulator Method in Microalga Growth with Control of Light Intensity

Abstract
Microalgae is an alternative energy source that considered capable of answering fuel oil scarcity problem. The growth of microalgae plays an important role in biomass production. One of the factors that influence the growth of microalgae is the control of light intensity so that it is necessary to adjust the intensity of the incoming light to produce maximum biomass. Control the intensity of light on the microalgae growth can be modelled in the form of differential equations and can be seen as a system. The control method chosen in this study was a linear quadratic regulator (LQR), as well as a comparison with the previous method, namely Pontryagin minimum principle (PMP). The simulation results show that at LQR an increase in the amount of biomass reaches 91.77% from initial condition. While the PMP has doubled from its initial condition.