Solar Air-Conditioning Systems

The chapter presents the recent studies focusing on optimizing the efficiency of air-conditioning (AC) systems using solar energy. For this purpose, several advanced AC plants (absorption, adsorption, and desiccant) are designed. Their technology and components are described in this chapter. It also discusses the energy intake of the solar energy use in air-conditioning, especially in rural regions where the electricity shortage is frequent, as well as the reduction of the energy costs and the pollution rate. A comparison between solar AC systems and traditional AC systems at the level of the designs, costs, and effectiveness is made at the end of the chapter

Application of a controlled outside cold airflow by a PID controller to improve the performance of a household refrigerator

The present paper aims to prove the efficiency of using the cold to improve the performance of a household refrigerator. It is produced naturally in countries that are characterized by a severe wintry climate. The cold airflow is spread out inside a cavity covering the side wall of the appliance, which is connected to the inlet and outlet ducts. For that purpose, a Simulink model is proposed to model this installation. The internal air temperature is computed according to the evaporator temperature and the outside cold airflow that is also computed according to the outside temperature and controlled by a PID controller. The simulation results show that when the internal air temperature is higher than the desired one and the outside temperature is low enough, the controlled cold airflow used as a second cooling source allowed to speed-up the cooling inside the refrigerator compartment of about 36.21% and to reach an energy saving of about 36.23% compared with the classical thermostatic control

FPGA based co-design of a speed fuzzy logic controller applied to an autonomous car

This paper invests in FPGA technology to control the speed of an autonomous car using fuzzy logic. For that purpose, we propose a co-design based on a novel fuzzy controller IP. It was developed using the hardware language VHDL and driven by the Zynq processor through an SDK software design written in C. The proposed IP acts according to the ambient temperature and the presence or absence of an obstacle and its distance from the car. The partitioning of the co-design tasks divides them into hardware and software parts. The simulation results of the fuzzy IP and those of the complete co-design implementation on a Xilinx Zynq board showed the effectiveness of the proposed controller to meet the target constraints and generate suitable PWM signals. The proposed hardware architecture based on 6-LUT blocks uses 11 times fewer logic resources than other previous similar designs. Also, it can be easily updated when new constraints on the system are to be considered, which makes it suitable for many related applications. Fuzzy computing was accelerated thanks to the use of digital signal processing blocks that ensure parallel processing. Indeed, a complete execution cycle takes only 7 us

Pseudo bond graph model of a thermo-hydraulic system

International audienceThe paper presents a pseudo bond graph model of a thermo-hydraulic system which is composed by two warm and cold water pipes, a plastic tank and an evacuation pipe. This model is designed on 20sim software and it allows varying the temperature, inside the tank, by acting on the mass flows of the warm and cold water, as well as on the evacuation pipe. A simulation is done for constant and variable water mass flows to show the efficiency of this bond graph model

A Data Acquisition with LabVIEW of Temperature of a water tank system: Comparative study with a Pseudo Bond graph Model

International audience— The paper presents the LabVIEW simulation of water temperature inside a plastic tank. This simulation is done in order to make a comparison in an open loop with a pseudo bond graph model, which is designed on 20sim software, and it allows varying the temperature, inside the tank, by acting on the temperatures and the mass flows of the hot and cold water, as well as on the output flow. The experimental results show the effectiveness of the bond graph model. However, it can't act against an abrupt disturbance which can exist during the real-time simulation

FPGA implementation of predictive control

International audienceIn this paper, we propose an implementation of a synthesizable VHDL program of generalized predictive control (GPC) without constraints on a map XC3S700A Xilinx Starter Kit using the Xilinx ISE 10.1 software. The control strategy was applied to a second order state system. The VHDL language was used as a programming tool. Real variables were described with the fixed-point representation to overcome the overflow problems during the computations in the VHDL program. The use of FPGA circuits presents a good choice regarding to the problem of computation time encountered in predictive algorithms. A GPC Matlab program was also implemented in order to make a performance comparison. The simulation results show a good set-point tracking