FUZZY LOGIC SYSTEM IN POWER SYSTEM USING WATER LEVEL CONTROLLER MIMO COMPUTER SYSTEM AND OVERVIEW
ABSTRACT
Water level control is highly important in industrial applications such as boilers in nuclear power
plants. In this work a simple water level indicator and a water level controller based on fuzzy logic is
proposed. The fabricated electronic level indicator defines 2 levels minimum and maximum through
LEDs. The fuzzy logic controller is based on Mamdani type Fuzzy Inference System. The fuzzy
controller has two inputs, error in level and rate of change of error and one output, valve position.
The fuzzy controller is implemented in MATLAB and then simulated in Simulink to test the behavior
of the system when inputs change. The response of the fuzzy controller is then compared with a
conventional PID controller. The results are shown sequentially and the effectiveness of the controller
is illustrated.
1.INTRODUCTION
In many industrial processes, control of liquid level is required. It was reported that about 25% of
emergency shutdowns in the nuclear power plant are caused by poor control of the steam generator
water level. Such shutdowns greatly decrease the plant availability and must be minimized. Water
level control system is a very complex system, because of the nonlinearities and uncertainties of a
system. Currently, constant gain PI controllers are used in nuclear organizations for boiler water
level control at high power operations. However, at low power operations, PI controllers can not
maintain water level properly. A need for performance improvement in existing water level
regulators is therefore needed.
