One important factor to produce  a qualified electricity is the stability of the system.  An unstable system resulted  an undamped oscilation of system, and the stable system can damp the oscilation quickly. Therefore, it is necessary to apply  a stability device to a power system and it is called a Power System Stabilizer (PSS). One of stability design is a feedback control design. Here, in this research, the state feedback control are designed for Single Machine Infinite Bus (SMIB) . The SMIB model is non linear therefore the feedback control can’t be designed directly. Some researchers do linearize the system before design the feedback control.  In this research, a nonlinear model of SMIB is build in a state space form. Subsequently, a fuzzification Takagi-Sugeno is applied. The state feedback controls are applied to design the control of SMIB fuzzy system, a state feedback gain is determined using method Routh Hurwitz. The determining the parameter of state feedback gain influence the performance of SMIB. Therefore, it is important to determine the suitable parameter such that the SMIB has the optimal performance. The Particle Swarm Optimization (PSO) is applied to optimaze the performance of SMIB. In these research, it is compared the performance of SMIB by applying between Routh Hurwitz, fuzzy Routh Hurwitz, PSO fuzzy Routh Hurwitz for state feedback control. The simulation result show that Performance of SMIB using The PSO Fuzzy Routh  Hurwitz state feedback can improve the performance of SMIB, but the performance of Efd become oscillate and this method influence by the chosen parameter.

Evaluation Board Microcontroller 89S51 / 89S82 / 89S53 (PEM-51) is a tool used to support microcontroller subject learning with an interactive methodology. PEM-51 consists of input / output modules that are integrated in one PCB board. The modules consist of a switch input, keypad module, LED module, seven segment display module, LCD display module, ADC (Analog to Digital Converter) module, DAC (Digital to Analog Conver) module, Stepper motor module. The software used in this tool is C using the Keil µVision4 compiler. The interactive learning process can be done by making a simulation circuit using Proteus software before implementing it to a microcontroller. With PEM-51, it is expected to increase student competency in studying Microcontroller courses.

— Mood lamp is a lamp made from RGB (red, green, blue) led that can be programmed based on its color through remote control, so that the color of the lamp can be determined by the user according to his mood. This lamp is designed using 89C2051 microcontroller with low power technology and uses RGB leds that can be programmed into several colors via a remote control. The remote control signal in this study uses the standard NEC remote code. The results of the led lights experiment can be programmed into 7 colors, namely red, blue, cyan, yellow, magenta, white, and green. The purpose of the results of this study in the future so that it can be used as a business opportunity in the field of creative industries, because this mood lamp can be used as a garden light, home porch lights, restaurants and cafes.