Electric drive with contactless synchronous motors

Contactless synchronous machines are considered, classification, description of structures, construction of analytical and numerical models for research calculations and design of inductor motors with electromagnetic excitation and with excitation from permanent magnets are given. Examples of design and research calculations of the operation of a synchronous drive of automation systems by means of a computational experiment are given.

Energy intensity of chopping fructified raspberry stems

The article analyzes the results of measuring the force required for the destruction of a dried raspberry stem by means of transverse action on it. There was used as a variant of the experiment the cutting of stem with support at one and two points, as well as breaking it with a distance between the supports of 30 and 54 mm. It was found that the force on the working body linearly depends on the diameter of the stem. The essential dependence of the required force on the method of action on the material was confirmed. It was revealed that the effort to cut a dried stem is significantly higher than the effort required to break it. To implement the breaking process, a working body in the form of a pair of horizontal twelve-blade rotors mounted with a radial overlap between them by an amount approximately equal to the distance between the outer edges of the adjacent blades is proposed. In this case, the rotors should have a diameter of about 200-210 mm. In addition, they must be equipped with a synchronous drive and shifted in phase by an angle of 150. As a result of modeling the phases of the destruction of the stem by transverse fracture, the force and energy parameters of the process were obtained. With a rotor length of one meter and simultaneous crushing of 25 stems, the average power required to drive is 9.3 kW, with a probability of peak val-ues of 16.4 kW. When calculating the strength, it should be taken into account that a distributed load of up to 12,400 N acts on the rotor shaft in the vertical plane and a distributed load of 2,750 N acts in the horizontal plane. A prototype grinder was tested and proven to work.