Comparison of PI, PD, and PID Controller in Hydroponic Plant Nutrient Concentration Control System

Abstract

Abstract: Hydroponics is a plant cultivation technique by utilizing water media and emphasizing the need for nutrients to grow. Each type of hydroponic plant requires a nutrient solution with different levels of concentration. If the concentration is low, it will reduce the effectiveness of nutrients so that additional nutrients are needed. Meanwhile, if it is excessive, the plant will wither and even die. In this study, Proportional (P), Integral (I), dan Derivative (D) controller is used. PI, PD, and PID controllers were designed, then tested on a nutrient concentration control system to get the best performance. If the error is positive, it indicates the plant to approach the threshold of excess nutrients, so the controller will move the servo motor to open the water valve. On the other hand, if the error value is negative, it indicates that the plant to approach the nutrient deficiency threshold, so that the nutrient solution valve needs to be opened through servo motor movement. The obs erved variables are error rate and delta error. The test results show that the use of a PID controller with Kp=0.5, Ki=1, and Kd=1 gives a fairly good performance with relatively small error rates and delta error, namely 4.997 (0.83%) and 1.804.