positivos obtidos propiciam oportunidades para novas aplicações e novas pesquisas. Palavras-chave: corrente iônica; motor a combustão interna; detonação. ABSTRACT The laws that restrict pollutant emission levels and the competition among manufacturers fostered the development of more efficient internal combustion engine management systems. However, the lack of sensors to identify the properties of combustion, and which are economically viable, hinders the development of new systems. In order to

more »

... address such limitations, this investigation proposes using the ionic current sensor with two purposes: identification of combustion and knock phenomena. The combustion identification is currently identified by the camshaft position sensor installed in the motor, which becomes more expensive for the management system. An alternative is using the spark plug, already installed inside the engine cylinder, such as ionization sensor of air/fuel mixture during combustion. Comparing the area under the curve of the ion current signal during combustion to the area under the curve during admission, it was found that it is feasible the use of ionic current signal to replace one feature of the camshaft position sensor. Concerning the identification of the knock phenomenon, it was shown that the use of the ionic current sensor allows the removal of the knock sensor. For this, the correlation between the energy signal in a frequency range of the ionic current harmonic with the energy of the signal from the knock sensor was performed Therefore, the use of spark plugs as sensors is very promising, in replacement to two existing sensors. Moreover, the positive results provide opportunities for new applications and researches. Tabela 1-Sequência de expansões 1-3-4-2 para um motor quatro tempos com 4 cilindros em linha. Cilindro 0 -180 (graus) 180 -360 (graus) -540 (graus) 540 -720 (graus)