Provided is a protective cover system including a first protective cover and a second protective cover, both include a polymer and being pre-formed into a curved shape so as to accommodate at least a part of a wind turbine blade to be protected, each of the first and second protective covers has a tip end and a root end, wherein the first protective cover includes a first overlap portion at the root end, and the second protective cover includes a second overlap portion at the tip end, wherein the shape of the first overlap portion is substantially complementary to the shape of the second overlap portion such that when overlapping the first and second overlap portions, the resulting cross section of the overlapped overlap portions substantially corresponds to the cross sections of the first or second protective covers outside the overlap portions.

Provided is a method for manufacturing a shell of a wind turbine blade having improved leading edge erosion protection, wherein the method includes the steps of: (a) providing a preform of the shell, (b) providing a protective cover for protection of the shell, (c) arranging the protective cover at a portion of a leading edge of the shell, so that an erosion protected shell is obtained, and (d) casting the erosion protected shell, so that the shell of the wind turbine blade having the improved erosion protection is obtained. Also provided is a method of manufacturing the wind turbine blade and to a shell, a wind turbine blade and a wind turbine.

The present invention discloses a coating monitoring system of wind turbines, comprising a monitoring object having at least one coating on the surface. A coating monitoring module is coupled to the monitoring object, and the coating monitoring module comprises a MEMS system including a signal generating device, and a printed circuit board connected to the MEMS system. The coating monitoring module measures a measured coating impedance value of the monitoring object. A potentiostat, calculating an actual coating impedance value of the monitoring object, is connected to the monitoring object. And a computing device coupled to the coating monitoring module, the computing device correcting the measured coating impedance value based on the actual coating impedance value.

A wave energy converter utilizes a flotation module that rises and falls with the passage of waves, a submerged tube containing a constriction which multiplies the speed of the water passing therethrough, a turbine (or other hydrokinetic apparatus) positioned so as to extract energy from the accelerated flow of water within and/or through the tube, and a submerged gas- or liquid-filled chamber housing one or more energy conversion components (e.g. generators, transformers, rectifiers, inverters). By providing a chamber in proximity to the turbine, generators can be placed in closer proximity to the turbine that turns them, and the shared shaft can be shorter than if the generators were placed in the buoy adjacent to the surface.

A scroll compressor may include a casing configured to receive a rotation shaft and a driving unit; a compression unit provided with a frame configured to rotatably support the rotation shaft, a first scroll fixed to the casing, and a second scroll configured to be connected to the rotation shaft and engaged with the first scroll. An oldham ring is provided with a plurality of key portions to guide the second scroll to perform an orbiting movement, wherein at least one of the frame, the first scroll, and the second scroll includes a respective key groove formed to receive a respective key portion; and a respective wear-resistant member mounted to cover an inner surface of the respective key groove in contact with the respective key portion.

A wave energy converter utilizes a flotation module that rises and falls with the passage of waves, a submerged tube containing a constriction which multiplies the speed of the water passing therethrough, a turbine (or other hydrokinetic apparatus) positioned so as to extract energy from the accelerated flow of water within and/or through the tube, and a submerged gas- or liquid-filled chamber housing one or more energy conversion components (e.g. generators, transformers, rectifiers, inverters). By providing a chamber in proximity to the turbine, generators can be placed in closer proximity to the turbine that turns them, and the shared shaft can be shorter than if the generators were placed in the buoy adjacent to the surface.

Methods of operating a variable speed wind turbine as a function of wind speed are described. The wind turbine has a rotor with a plurality of blades and a generator. The generator has a design rotor speed which varies so as to follow a theoretical generator rotor rotational speed curve describing the rotational speed of the rotor as a function of wind speed. The method comprises determining an erosion risk condition of the blades, determining erosion damage of one or more of the blades accumulated over time and changing the rotor rotational speed from the design rotor speed as a function of the determined erosion risk condition and the determined accumulated erosion damage. Wind turbines configured to carry out such methods are also described.

A vacuum pump system includes an air-cooled, O-ring sealed vacuum pump and an oil management system with an LED illuminated clear tank for observation of the oil condition as well as a large oil inlet and outlet for rapid and safe oil changes while the pump is operating. The oil management system is also configured to prevent oil from the sump from being drawn into an evacuated AC/R system when the pump is stopped and the intake ports are not sealed from the high vacuum AC/R system. The oil management system includes a preferential vacuum relief system that allows air instead of the oil from the sump to be drawn back into the evacuated lines.

A vacuum pump system includes an air-cooled, O-ring sealed vacuum pump and an oil management system with an LED illuminated clear tank for observation of the oil condition as well as a large oil inlet and outlet for rapid and safe oil changes while the pump is operating. The oil management system is also configured to prevent oil from the sump from being drawn into an evacuated AC/R system when the pump is stopped and the intake ports are not sealed from the high vacuum AC/R system. The oil management system includes a preferential vacuum relief system that allows air instead of the oil from the sump to be drawn back into the evacuated lines.

Provide is a lightning discharge system for a wind turbine including a hub, a spinner defining a protection space wherein the hub is arranged, a blade fixed to the hub, and a nacelle. The discharge system includes a blade band attached to the blade, a ring facing the nacelle and attached to the band and to the nacelle, a respective contact device connecting the band to the ring and the ring to the nacelle. The band and the ring are arranged in the space, and the ring is further attached to the hub such that it faces the nacelle through a rear opening of the spinner.