TWK-ELEKTRONIK: New Products for the Wind Power Industry

The wind power industry can look back over a successful 20-year period. The market share of current produced using renewable energy in Germany has now reached the 25% mark. The majority of this is generated using wind power. Further growth rates are to be anticipated thanks to the continuing energy revolution.

TWK-ELEKTRONIK has been involved from the very beginning and remains one of this industry's most important suppliers in the field of sensors. The company's regular customers include major and innovative wind power plant manufacturers. In recent years, the product range has been extended and rounded off by numerous devices.

These devices include the new vibration sensors NVA as well as the tried-and-tested electronic switching cam encoders NOC, vast quantities of which are used by renowned wind turbine manufacturers for pitch and yaw regulation. The vibration sensors and switching cam encoders, in particular, have been developed in close co-operation with wind power customers to meet the specific requirements important to the wind power industry. Long-term contact with customers constantly leads to progressive and tailored products which are also very interesting in terms of price.

Over the past few weeks, this co-operation has seen the launch of another electronic switching cam encoder model; it offers a compact design – 64 mm outside diameter – and contains 4 switching contacts. The number of switching contacts has therefore been increased from two to four without changing the design size. All of the four switching outputs' cams can be individually pre-set, enabling them to be individually adapted to the application. It should be noted that, in addition to the cam function, a multiturn rotary encoder with a resolution of 12 or 13 bits for precise position recording is also integrated into the electronic switching cam encoders. The available interfaces are CANopen, SSI and analogue.

The 4 switching outputs in the 64 mm design form consist of 2 mechanical relays (switches) and two PhotoMOS modules – these are galvanically separated semi-conductor switches. Up to 1 or 0.5 A and up to 60 VDC/VAC can be switched.

A cost-saving design is common to all of the devices. Specifically developed components of high quality, which do not reveal any unnecessary and therefore expensive features, are used. Only this enables the achievement of a price which meets the requirements of the customer and the supplier.

In addition to the switching cam encoder, the vibration sensor NVA, too, is not limited to merely recording the measured variable (vibration accelerations). It has a range of relay switching outputs which switch on exceeding specified acceleration values and thus indicate to the control system and the connected peripheral devices that a reaction is required. E.g. in the case of excessive transmission or rotor vibrations, the system is shut down; this is initialised by the NVA. The corresponding values can be parameterised by the customer. Or TWK sets all parameters as required in the factory. This is particularly interesting for series production.

Of course, development has not come to an end by any means. The concept of safety, in particular, is playing an ever increasing role. Due to Germanischer Lloyd guidelines, wind power plants have to meet higher standards of safety. TWK-ELEKTRONIK has now had a range of sensors certified to SIL2. Rotary encoders, with their diverse interfaces and safety profiles, are already virtually commonplace – PROFIBUS, PROFINET and CANopen, to name just a few. In all likelihood, Ethernet IP and EtherCAT are set to follow. The electronic switching cam encoder will be certified according to SIL2 at the beginning of next year to enable its use in the safety chain.

TWK-ELEKTRONIK's many years of experience are the prerequisite for good advice and the further development of the products – always with the objective of enabling us to offer inexpensive products oriented towards our customers' requirements.