Journal article Open Access
The paper presents the relevant topic of improving protection devices for asynchronous engines used in agriculture. We have also provided the data of technical and technological damage. There have been identified the main causes of asynchronous motor failure. You may also find a short list of the main existing protection systems for induction motors, the analysis of their shortcomings and prospects for further improvement. We have justified the structural scheme of a universal protective device, which consists of the following channels: a current overload control channel, a rotor seizure channel and a feed line phase failure monitoring channel. We have also given a circuit scheme of the proposed protective device and the description of the circuit operation in the operational mode as well as in various emergency modes. The use of a microcircuit-comparator of the type K554 CA3 (the operational amplifier) as a threshold element with an adjustable threshold voltage value is considered to be an original technical solution.