Abstract: A belt tension adjustment device includes a driving pulley attached to a power transmission shaft, a driven pulley arranged in a driven device, a tension pulley, a loop belt arranged between the driving pulley, the driven pulley, and the tension pulley, and configured to transmit a rotational driving force of the power transmission shaft to the driven device, and a tension adjustment mechanism to adjust tension of the loop belt. The tension adjustment mechanism includes a support shaft rotatably supported, a rotational operation mechanism to rotate the support shaft about an axis of the support shaft, and a rotating member coupling the support shaft and the tension pulley, configured to change a relative position of the tension pulley with respect to the driving pulley and the driven pulley in accordance with rotating of the support shaft.

Abstract: Embodiments according to the present invention provide methods and a system for a control approach that effectively maintains the DC link voltage at a constant set value under variable system conditions and keeps the converter operating within an optimal power factor range.

Abstract: An electromagnetic motor having a frame, and at least one disc rotatably mounted to the frame. At least one permanent magnet is mounted on the disc, and at least one electromagnet is mounted to the frame in magnetic proximity to the at least one permanent magnet. A battery is electrically coupled to the motor for powering the at least one electromagnet. A switch controls electrical power between the battery and the at least one electromagnet, and a sensing means is provided for controlling the switch to activate the at least one electromagnet with respect to the at least one permanent magnet to cause the at least one disc to rotate. Preferably, a generator is mechanically coupled to the motor and electrically coupled to the battery for generating electrical power to the battery, and a renewable energy source such as a photovoltaic cell is electrically coupled to the motor to supplement any net electrical loss.

Abstract: A method of operating a wind turbine, wherein the wind turbine may include rotor windings of an induction generator, which includes stator coils coupled to a voltage grid, fed with rotor currents by a feed-in unit are driven by a rotor of the wind turbine; wherein the frequencies of the fed-in rotor currents are controlled depending on the rotor rotation frequency and the feed-in unit is electrically decoupled from the rotor windings in the case predetermined variations of the grid voltage amplitude and the rotor current feed-in is resumed after the decoupling caused by the variation of the grid voltage amplitude, when the currents generated in the motor windings by the variation have declined to a predetermined value.