Deublin slip rings for the wind market.

Electrical slip rings handle a variety of industrial applications up to 60A and 5 MW. The devices usually configure easily for power or signal connections. The signal portion is often compatible with Ethernet, Profinet, RS-232, RS-485, RS-422, CAN, as well as generic analog or digital sensing and 24V control signals. A slip ring can be used in any electromechanical system that requires unrestrained, intermittent, or continuous rotation while transmitting power, or data, or both.

Contactless slip rings, a recent development, are based on inductively coupled power transfers. Inductivepower transfer applies the principle of electromagnetic inductance. A version that works with high efficiencies uses wireless power transfer that can harmonize itself in the field. This makes the system resistant to changes in environmental conditions and load variations.

These slip rings can mount at a variety of distances, although closer is better. Furthermore, they can transfer power through any non-metallic membrane, making mounting easier than traditional components. Power can transmit as a single load while a builtin data-communications system switches power as necessary to meet different device requirements off the wireless receiver. In this way, the slip rings are said to provide wireless power and data to pitch control in wind turbines, improving their efficiency by reducing the cost of maintaining and replacing existing mechanical slip rings and their carbon brushes.

The contactless design eliminates friction or heating between rotating and stationary-circuit contacts and provides a cost-effective alternative to mechanical slip rings. Unlike conventional slip ring applications, contaminants such as oil or dust in the nacelle do not affect the operation of the contactless slip ring. The units are said to be highly corrosion-resistant, waterproof (immersion rating of IP68) and compatible with existing power supplies and a range of communication protocols.

With up to 90% efficiency of inductive power transfer, the unit eliminates the excessive heat generation suffered by earlier generations of inductive power transfer designs. A standard supply can be used to provide power to the power transmitter and up to 750W can be drawn from the power receiver. The output voltage is held within a tight 1% tolerance.

Windpower Engineering & Development

Smalley Steel Ring Co. provides assembly materials for the wind industry.

Assembly tasks intersect in manufacturing, fastening and joining, and fabrication work. That becomes clearer when you consider that utility-scale turbines are so large they must be manufactured in sections or modules and then assembled close to the job site. Modular turbine designs are also necessary because all roadways have weight restrictions. A fully assembled nacelle of 2.5-MW nameplate could easily exceed any allowable highway load limit.

To get our arms around the assembly subject, let’s start in the shop. The advanced technology in wind turbines depends a lot on conventional manufacturing techniques, such as welding, often used to assemble a tower. One welding-machine manufacturer recently called on a linear motion and assembly-technology company to help build custom welding machines for the wind industry. Such welding equipment builds 45-m long turbine-tower sections. Typically, a machine rolls a metal plate into a cylinder called a can that measures some 9-ft long by 8 to 15-ft dia. Another machine then welds along longitudinal seams to complete the can and then circumferentially to join cans.

“Can” welders are usually suspended from a guide rail for outside welding. Most of the machine is stationary while a weld head moves short distances on two and three axes, both along and across the seam. A linear control actuator at the end of a horizontal arm determines the motion of the weld head.

Assembling gearboxes give some scale to the tasks. The physical sizes of a gearbox and carrier components range from 4-ft cubes to one 12 ft on a side. When assembling hydraulic equipment to gearboxes and cylinders, color coding fittings help prevent assembly errors on a shop floor, and potentially catastrophic failures on a system in service.

Even a simple pin can assist assemblies. One in particular is a semi-permanent quick locking device that speeds assembly work by replacing other labor intensive fastening combinations such as a clevis pin and cotter pin, a pin and retaining ring, or a nut and bolt.

Windpower Engineering & Development

Windpower Engineering & Development

The new Electrical Slip Ring brochure (#SR1104 US) replaces a previous version.

The company says its slip rings are optimized with material configurations tested and proven for hundreds of millions of cycles, which translates into many years of trouble-free operation with unsurpassed performance, significantly reducing down-time and maintenance costs.

The electrical slip rings feature flexible engineering to support unique requirements and allow for easy replacement of existing slip ring brands by the end user. DEUBLIN designs slip rings to a variety of EMI, operating temperatures, storage temperatures, acceleration, mechanical vibration, and mechanical shock requirements as required by the customer application. The company’s rotary union and slip ring combinations have a unique plug-and-play configuration to reduce installation and maintenance time. Other design innovations include slip rings that meet requirements such as RF shielding, mixed signal handling, high frequency impedance matching, reduced temperature generation, and miniaturization.

A slip ring allows transmitting power and electrical signals from a stationary to a rotating structure. Also called a rotary electrical joint, collector, or electric swivel, a slip ring can be used in any electromechanical system that requires unrestrained, intermittent, or continuous rotation while transmitting power, or data, or both. Typically, it is compromised of a graphite or metal contact brush which rubs on the outside diameter of a rotating metal ring. As the slip ring turns, the electrical current or signal is conducted through the stationary brush to the metal ring making the connection. A new Electrical Slip Ring brochure is available (#SR1104 US), that replaces the SR102 US.

DEUBLIN Co.
www.deublin.com

Windpower Engineering & Development

UEA Slip Rings come in a variety of bore sizes, from 0.500 to 14.00 in.

A provider of parts and engineering services to wind power industry in North America and a manufacturer of wind turbine and custom components for motion applications worldwide, have announced their partnership in design, manufacture, and distribution of slip rings. UEA slip rings are said offer design versatility as component-kit rings or as completed, ready-to-mount assemblies with optional pre-wired harnesses. A wide selection of circuitry is available, with many combinations of amperage and voltage, ac or dc. The compact design is made possible by brushes stacked on alternating sides. UEA Slip Rings come in a variety of bore sizes, from 0.500 to 14.00 in. This approach translates into opportunity for Availon and UEA to develop more new aftermarket products.

Mark Hanawalt, UEA’s President, adds, “We manufacture custom-designed wind turbine slip rings that match exact customers specifications and are delivered in a matter of weeks.”

The partnership between Availon and Waverly, Iowa-based UEA will let Availon sell replacement components for aftermarket use in wind turbines. Stock will be kept in the Availon’s Iowa and Texas locations. The two companies will work together to facilitate the development of new UEA products and aftermarket solutions for many types of wind turbines.

Availon Inc.
www.availon.com

United Equipment Accessories
http://www.uea-inc.com/

Windpower Engineering & Development

Slip rings from UEA can be fitted with connectors and tested to client specs before delivery.

One option that sets UEA slip rings apart from most others manufacturers are its custom wiring harnesses. These harnesses are built in-house to attach to either or both the center leads from the center core stack and/or the brush leads or outer portion of the slip ring assembly. Adding plugs or connectors to the outer ends of the harnesses lets the slip-ring assembly become a ‘plug and play’ component of the customer’s complete electrical wiring system.

Harnesses assembly begins with discrete wires of the correct AWG size, voltage rating, environmental rating, etc. that are often color-coded to meet a specification. The harnesses may also include or be composed of one or more jacketed cables of the required size and ratings. Discrete wires in the harnesses are ink-jet marked with the circuit number to match the correct circuit in the slip ring and often a customer specified function for that circuit. These markings are spaced about every 2 in. along the length of the wire to make the circuit easily identifiable at any position along the full length of the harness. Wires and cables are cut to a length to meet customer specified overall lengths when attached to the slip ring, bundled for use in either the brush or center harness and supplied to the Harness Layout Department. If any one of a wide variety of connector types or brands is to be attached to the harnesses, the insulation is stripped from one end of the individual wires and terminals are attached or the wires are soldered to the connectors. At that time, individual wires from the connector, or connectors if the harness includes more than one, are put through individual holes in a ‘die’ which puts the wires in the correct order to match the center core leads from the core stack of rings and insulators, or to provide a more orderly ‘break-out’ of the leads to the brushes. As the wires are pulled back through the die, they are taped to keep the wires in a correct order. A twist is often added to the harness, retained by the tape, to make the harness more flexible. Some harnesses are supplied with only the taped covering but many also add a heat-shrink tubing jacket for better sealing or an over-braided nylon thread covering for increased abrasion resistance. Completed harnesses are then attached to their slip-ring assemblies and then to a test stand for complete continuity, shorting, and other required tests. At this time point, the harnesses with connectors becomes an advantage to UEA because they are more easily attached to the test stands using mating harnesses than would be assemblies with only individual wires on the harness ends.

– Brent Jensen, Director of Engineering

United Equipment Accessories Inc.
http://www.uea-inc.com/

Windpower Engineering & Development

The Proxi-Ring 480 is said to make wind-energy generation more cost-effective by increasing uptime and reliability and eliminating costs of maintaining and replacing mechanical slip rings.

The manufacturer of industrial wireless power devices announced the successful trial of the Proxi-Ring 480, a contactless slip ring that provides wireless power and data to pitch-control systems in wind turbines. The Proxi-Ring 480 is said to make wind-energy generation more cost-effective by increasing uptime and reliability and eliminating costs of maintaining and replacing mechanical slip rings.

“Our contactless slip ring has been working flawlessly ever since installation in a hydraulic wind turbine in Spain eight months ago,” says VP PowerbyProxi Fady Mishriki. “It replaced a mechanical slip ring that was causing problems several times a week and this frequency was increasing as the turbine aged. The faults are hard to diagnose due to their intermittent nature and because turbines are stationary when tested. We set out to prove our wireless device delivers significant benefits over mechanical slip rings and we’ve done that.”

“The plug and play Proxi-Ring 480 was easy for our technicians to get working in the 1.3-MW turbine and it has performed perfectly,” says Jose Rodriguez, Managing Director of IM FutuRe, an O&M company. The slipring passes the required level of power and communication signals wirelessly and without friction. Proxi-Rings allow 360◦ continuous rotation and are corrosion-resistant and waterproof. Unlike mechanical slip rings they require no cleaning or maintenance because contaminants such as oil or brake dust do not affect operation.

PowerbyProxi

www.powerbyproxi.com

Windpower Engineering & Development

A holder designed by Availon engineers will carry graphite brushes designed by Schunk.

A wind turbine service company North American industry, Availon Inc, says it has been named a distributor for Schunk Graphite Technology LLC (SGT).  Availon will now offer customers products from Schunk including brush holders, carbon brushes, slip rings, and other components critical for reliable operation and higher availability of wind turbines.

“Availon and Schunk have a successful history in Europe working together in the challenging wind industry market,” says Availon North America’s President Steve Thompson. “Now we share the common goal of advancing the growth of wind energy in the United States and Canada. It is only natural that we join forces to offer better service and state-of-the art parts to our customers.”

“Schunk’s brush holders and carbon brushes will play significant roles in implementing one of the money-saving upgrades offered by Availon,” says its North America’s Director of Sales John Boorman. “The brush holder upgrade decreases the time required to replace brushes and prevents small parts from being lost in the slip ring compartment during replacement. The innovative brush configuration reduces irregular wear and extends service life up to 50%.”

Availon specializes in parts and services for GE, Vestas, and Siemens turbines, and is expanding to other turbines. In addition to being a primary supplier for SSB and Duradrive parts, Availon Inc. is also an exclusive vendor for Bachmann, Leonard+Bauer, and Convertec parts. Availon says its global portfolio includes spare parts supply and management, end of warranty inspections, individual turbine optimization, turbine upgrades, field services, remote monitoring, and operations and maintenance.

Availon Inc.
www.availon.com

Schunk Graphite Technology LLC
www.schunk.com

Windpower Engineering & Development

Electrical slip rings handle a variety of industrial applications up to 60A and 5 MW. The devices usually configure easily for power or signal connections. The signal portion is often compatible with Ethernet, Profinet, RS-232, RS-485, RS-422, CAN, as well as generic analog or digital sensing and 24V control signals. A slip ring can be used in any electromechanical system that requires unrestrained, intermittent, or continuous rotation while transmitting power, or data, or both.

Contactless sliprings, a recent development, are based on inductively coupled power transfers. Inductive-power transfer applies the principle of electromagnetic inductance. A version that works with high efficiencies uses wireless power transfer that can harmonize itself in the field. This makes the system resistant to changes in environmental conditions and load variations.

These sliprings mount at a variety of distances. Furthermore, they can transfer power through any non-metallic membrane, making mounting easier than traditional components.

Power can transmit as a single load while a built- in data-communications system switches power as necessary, to meet different device requirements off the wireless receiver. In this way, the slip rings are said to provide wireless power and data to pitch control in wind turbines, improving their efficiency by reducing the cost of maintaining and replacing existing mechanical slip rings and their carbon brushes.

Windpower Engineering & Development

In pitch slip rings, the trend in new designs is on two fronts. “First, as turbine designs increase in power output and size, the demand on the pitch slip ring is higher power transfer,” says Moog’s Senior Business Development Manager Steve Black. “Second, data handling and signal demands are increasing to provide additional condition monitoring in the hub.  It is critical that the contact technologies be durable enough to handle power peaks at the extremes of operation.”  Equally important is a need to protect data lines from potential cross talk with power lines.

Another trend is toward more complete pitch controls. “These would include hub controls, pitch drive motors, power back-up, blade monitoring, and the slip ring to transfer the power and control signals through the rotary interface,” says Black. The company supplies complete systems to the OEM and also offers aftermarket pitch slip rings to improve system performance.

Also look too for new pitch control slip rings in the aftermarket. “The wind turbine service market is growing tremendously as the turbine population ages and asset owners are look for ways to control maintenance costs and maximize turbine availability and output. Products should be able to replace slip rings in older turbines with long-life, high-reliability design to provide pitch slip rings that can operate for years without maintenance.

“Ideal pitch slip rings should be installed and forgotten. Many designs in use today require periodic maintenance to clean away wear debris, flush out oil and dirt, and relubricate. Often replacement of the entire slip ring is done too frequently.  Keeping the turbine technicians out of the nacelle will keep costs down and outputs up.  That is the goal for asset owners and the focus of efforts in the aftermarket portion of our wind energy business.

The high-reliability quest has let some companies devise non-contacting slip rings. One is an inductively coupled power transfer device. Inductive-power transfer applies the scientific principle of electromagnetic inductance. The manufacturer of one says its sliprings work at high efficiencies by using wireless power transfer that can harmonize itself in the field. This makes the systems resistant to changes in real world environmental conditions and load variations, says developer New Zeeland-base PowerbyProxi.

For wireless power, transmission distances can reach to 6 to 8 ft, but efficiency levels between transmitter and receiver are low. Commercial applications in which transmission distances are less than 8 in. allow efficiencies over 90%.

Power transmits as a single load while a built-in data-communications system switches power, for example, to meet different device requirements of wireless receivers. In this way, the slip rings provide wireless power and data to pitch control in wind turbines, improving wind turbine efficiency by reducing the cost of maintaining and replacing existing mechanical slip rings and their carbon brushes. Any size turbine can be supported, says the company.

Windpower Engineering & Development