Investigation of the effect of resistive components of the measuring circuit in the accuracy of measurement of the ion current in the combustion chamber of internal combustion engines
Abstract
Investigation of the effect of resistive components of the measuring circuit in the accuracy of measurement of the ion current in the combustion chamber of internal combustion engines
Incoming article date: 24.10.2016For basic research flame ionization process is necessary to obtain the true value of the ion current on the probe, taking into account the errors of the measuring circuits. To study the processes of ionization in the combustion cameo widespread ionic current sensors in the presence of the resistive component of the measurement circuit, such as current-limiting elements in the circuits connecting to the ignition coil high-voltage output or measuring shunt. This article describes how to account instrumental errors introduced by such measuring systems, as well as the proposed formula of the transition from the signal values obtained experimentally to the true value of the ion current. The results of the calculation of the reduced value of the ion current to the experimentally obtained signal. The possibility of making instrumental error of up to 40% in amplitude at signal peaks. It is shown that the construction of I-V characteristics of the ionization probe must be considered instrumental error introduced by the resistive components of the measuring circuit.
Keywords: ion current, the electrical conductivity of the flame, the measuring circuit, the instrumental error of measurement, resistive voltage divider, ICE