A method for detecting a fault, it is rotating stall in the case of a converter-fed compressor

摘要

The invention relates to a method for detection of a failure rotating stall in the case of a compressor (12), by means of a converter-fed three-phase electric motor (8) is driven. According to the invention, a from measured power converter - output currents (i_S1, i_S2, i_S3) and a measured rotational-speed-proportional signal (ω) calculated torques - estimated value with one of a measured and a predetermined rotational-speed-proportional signal (ω, ω *) determined moments - desired value (m *) is compared in such a way that in the case of a signal (s_Rs) is generated, indicating that the case of a fault has occurred rotating stall. Thus, in the case of a compressor (12) which, by means of a converter-fed three-phase motor (8) is driven, the disturbance rotating stall without pressure sensors and / or vibration sensor are determined.