Suresh Gyan Vihar University Journal of Engineering & Technology (An International Bi‐Annual Journal) Vol . 3, Issue 2, 2017, pp 9-16 ISSN: 2395‐0196 9 TLBO based Load Frequency Controller Chirag Arora 1 , Dr. Nagendra Kumar Swarnkar 2 , Rahul Sharma 3 1 M.Tech. Scholar, Department of Electrical Engineering, Suresh Gyan Vihar University, Jaipur, India chirag.arora@mygyanvihar.com 2 Professor, Department of Electrical Engineering, Suresh Gyan Vihar University, Jaipur, India nagendra.swarnkar@mygyanvihar.com 3 Assistant Professor, Department of Electrical Engineering, Suresh Gyan Vihar University, Jaipur, India rahul.sharma@mygyanvihar.com Abstract: The goals of the LFC (Load Frequency Control) are to maintain zero steady state errors in a multi area interconnected power system with computer based control systems and multiple inputs, an automatic generation control system can take into account such matters as the most economical units to adjust, the coordination of thermal, hydroelectric, and other generation types, and even constraints related to the stability of the system and capacity of interconnections to other power grids. A proportional integral derivative controller (PID controller) is a generic loop feedback (controller) widely used in industrial control systems. A PID controller attempts to correct the error between a measured process variable and a desired set point by calculating and then instigating a corrective action that can adjust the process accordingly and rapidly, to keep the error minimal. The PID controller calculation involves three separate parameters; the proportional, the integral and the derivative values. The proportional value determines the reaction to the current error, the integral value determines the reaction based on the sum of recent errors, and the derivative value determines the reaction based on the rate at which the error has been changing. The weighted sum of these three actions is used to adjust the process via a control element such as the position of a control valve or the power supply of a heating elements. Keywords-- Load Frequency Control, constant frequency, PID controller, Jaya technique. I. INTRODUCTION oday in electric power system Load–frequency control (LFC) is important field for design and operation. In an interconnected power system, the generation of power within each area has to be controlled so as to maintain the scheduled power interchange. The modern power systems with industrial and commercial loads need to operate at constant frequency with reliable power. Owing to the continuous growth of electrical power system in size and complexity with increasing interconnections, the problem of power and frequency oscillations due to unpredictable load changes, has become increasingly serious. In the large scale electric power systems with interconnected areas, LFC plays an important role. The objective of the LFC in an interconnected power system is to maintain the frequency of each area within limits and to keep tie-line power flows within some pre-specified tolerances by adjusting the MW outputs of the generators so as to accommodate fluctuating load demands. The load frequency control of an interconnected power system is being improved over the last few years. This paper work uses a new Artificial Intelligence (AI) technique (ACO) for optimal tuning of PID controllers. The motivation behind this research is to prove and demonstrate the robustness of ACO based PID, and to improve the transient response of frequency deviation under various loading conditions in presence of system nonlinearities. II. SYSTEM MODEL In an interconnected power system there are number of generators supplying the power system load, so there must be some methods, by which change in load could be allocated to each generator. This mechanism by which load is allocated to a generator can be controlled by system consisting of number of units which are being modelled here: ● Mathematical modelling of load The load on the power system consists of a variety of electrical drives. The equipment’s used for lighting purposes are basically resistive in nature and the rotating devices are basically a composite of the resistive and inductive components. The speed-load characteristic of the composite load is given by: ee L P P D      (1) T