Design and implementation of a fuzzy controller which intervenes EFI system in a vehicle, for use HHO as a supplementary fuel

This article refers to a study on the behavior of an internal combustion engine of a vehicle when you add oxyhydrogen (HHO) as a supplementary fuel, produced from a modified alkaline type electrolyzer, called HHO generator. The first stage consists of a theoretical and experimental analysis of what happens in the internal combustion engine by adding the oxyhydrogen. As a result of this first stage a slight increase in fuel efficiency and idle speed unstable was presented by the engine, because the vehicle´s computer is not designed to operate with the addition of HHO. The second stage corresponded to design a controller based on fuzzy logic and free software and hardware, whereby an increase in fuel efficiency and a cancellation of the flaws founded in engine behavior was intended. The third stage involved the controller implementation in the vehicle, which begin taking the signals from air flow and oxygen sensor, pass them by the controller and then deliver them to the vehicle´s computer again without it noticing the change. In the fourth stage the same tests as in the first stage were made, so is able to verify and validate the data, where the greatest increase was obtained in the fuel efficiency of the vehicle, combined with a better engine performance at different performed driving conditions, all without sacrificing engine power and torque.