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Gear adaptive variator may be the toothed transmitting with the adjustable transfer ratio which is adapting to the adjustable loading. Unsuccessful tries of creation of a equipment variator had been undertaken repeatedly. The primary problem is-maintenance of continuous engagement of Variator Gearbox cogwheels of a variator. The decision of this problem could be based on use of a kinematic chain with two degrees of freedom. Earlier it had been proved that kinematic chain with closed contour possesses the result of power adaptation. The gear variator can be performed in the kind of the shut differential system. The external variable technical loading changes the transfer ratio itself without any control system. The apparatus variator opens essentially new concept of creation of adaptive engineering for machines with variable technological resistance (for instance, adaptive gearbox of car). The idea of a gear variator is founded on discovery «Impact of power adaptation in mechanics» which is published in leading editions of world press. In the paper the bases of the theory of a gear adaptive variator are offered.
There are different types of DC drive setups with the designation dependant on the foundation of their DC current. This is the case in emergency backup systems. For example, power vegetation have a bank of batteries supplying DC current to emergency oil pumps that supply essential oil to the bearings of a turbine during an emergency shutdown. A second source of DC current could possibly be from a (Motor-Generator) MG established. In this instance, the motor drives a DC generator that generates the DC current. These first two types of drives provide pure DC current, therefore they do not produce any significant electrically induced indicators when it comes to vibration. The last kind of DC drive, and the one that will be discussed in this paper, uses silicon managed rectifiers (SCRs) to rectify AC current into DC Current. These drives produce a DC signal with AC pulses that correspond to the firing of the SCRs. These pulses or lack thereof in the case of failed SCRs and or gating problems produce vibration signals which can be analyzed to determine the source of the defect. Improper tuning of variable speed drives can also generate vibration problems.

Rectification: The first concept that should be understood in regards to DC drives is usually rectification. Rectification is the process of switching AC current into DC current. Pictured below can be a fifty percent wave rectifier and the resulting result. Only the positive part of the current Al passes through the rectifier.

Full Wave Rectification: The above plot shows a normal spectrum from a current probe on the lead to a DC drive. As is seen, the only main component reaches 360HZ. This is normal due to the non-sinusoidal character of the current waveform.