DEIF’s anti knocking regulator (AKR 3) is a state-of-the art unit with knocking sensing based on single cylinder detection.
For correct knocking sensing, the AKR 3 uses digital FFT (fast fourier transformation) to break down vibration data into individual frequencies and individual levels.
The use of FFT enables the AKR 3 to create an engine “image”, which represents the frequencies and levels produced by the normal engine state, including gear wheel noise, bearing noise, normal combustion noise etc.
Filtering the “image” frequencies precisely highlights knocking frequencies for monitoring and taking action when needed.
In combination with the DM 400 Gas and communication to the ignition system, the AKR 3 offers the possibility to control the ignition-firing angle for each individual cylinder and thereby prevent knocking without having to decrease the genset power output.
DEIF biogas solution: Raising efficiency - Nimtofte Biogas: Aarhus, Denmark (abstract)