Control system EDC

The electronic control system of diesel engine EDC for Common Rail includes three big systems:

Gauges for registration of parametres of an operational mode which transform various material parametres to electric signals. ECU for generation of target electric signals on the basis of signals from gauges and the set algorithm. Drives for transformation of target electric signals ECU to mechanical parametres.

The gauge of frequency of rotation of a cranked shaft

Position of the piston in the engine cylinder is solving in definition of the moment of injection of fuel in the combustion chamber. As pistons through rods are rigidly connected with cranked shaft, the gauge of position of a cranked shaft hands over to the block of management the information concerning position of all pistons. The inductive gauge on angular speed defines frequency of rotation of a cranked shaft, and this important entrance variable is transferred ECU.

The ferromagnetic rotor with 60 teeths is fixed on cranked to a shaft, thus on a rotor there is no 2 teeth. This interval is located in certain position in relation to a cranked shaft and position of the piston in the first cylinder. The gauge represents a constant magnet and a metal core with the inductive coil. At passage about a pole of the gauge of teeths of a rotor in it the sinusoidal pressure which amplitude increases with increase in frequency of rotation of a cranked shaft is induced.

The gauge of position of a camshaft

The camshaft operates inlet and final valves and rotates with frequency twice less frequencies of rotation of a cranked shaft. At piston movement to the top dead point camshaft position specifies, what piston is in a step of compression or a release step.

The gauge of position of a camshaft works on effect of the Hall. The short-term signal of the gauge informs ECU that the piston of the first cylinder has passed in a compression step.

Temperature gauges

Temperature gauges are established in various places of the engine and intended for measurement of temperature of the cooling liquid, air arriving in the engine, engine oil and fuel coming back in a fuel tank. A basis of each gauge is the resistor which resistance changes depending on temperature with negative temperature factor (NTC). The Power failure on the resistor through analogue-digitizer (ADC) is transferred ECU. The gauge characteristic is written down in memory ECU as pressure function.

Measuring instrument of the expense of air

The system of injection of fuel is intended for exact dispensing of fuel depending on quantity of arriving air at various power setting. Air and fuel proper correlation is necessary for reduction of quantity of harmful substances in the fulfilled gases. It demands use of gauges which precisely register an actual stream of air arriving in cylinders of the engine during each moment.

Accuracy of the gauge should not depend on pulsations, system рециркуляции the fulfilled gases and temperature of air arriving in the engine. To these requirements there corresponds a measuring instrument of the expense of air with a heated up thin film. The micromechanical measuring system registers a stream of air and its direction.