Wireless temperature monitoring system for wind turbine gearboxes based on Profinet
The wind turbine gearbox is an essential mechanical component in a wind turbine. The temperature inside the gearbox can reflect the operating status of the gearbox. In the following case study, Hongke Technology Co, Ltd, MSR distributor in China, introduces a system that wirelessly detects the temperature inside the gearbox and integrates the MSR385WD data logger into the Profinet network to realize real-time temperature monitoring and fault warning.
Author: Amy Mai, Head of Environmental Monitoring Business Unit, Hongke Technology Co, Ltd
The Profinet network technology
Profinet is an open industrial Ethernet communication protocol proposed by the PROFIBUS & PROFINET International Association. Profinet applies TCP/IP and related information technology standards and is an industrial real-time Ethernet. Profinet is characterized by high compatibility, fast speed and high real-time. Its communication rate is up to 100 Mb/s. The bus cycle time of general data transmission is hundreds of microseconds or less. Profinet plays an important role in a variety of applications in the process industry, such as wind power generation, boiler control, oil extraction, fire protection and gas systems, etc. Profinet technology represents a new communication solution for the field of industrial automation, i.e. the entire plant is connected to a network.
Function of a wind turbine gearbox
The gearbox is an important mechanical component widely used in wind turbines. Its main function is to transfer the energy produced by the wind turbine under the influence of the wind to the generator and to give it the appropriate speed. Insufficient gearbox oil injection, high oil temperature, bearing damage, friction or over-tightened seals lead to a high internal temperature of the gearbox. Recording and monitoring the temperature inside the gearbox in real time can help to identify problems and rectify them in good time to prevent further damage to the gearbox. Since the internal gearbox both rotates and revolves, wireless transmission of temperature data is undoubtedly the best choice.
The temperature transmitter module is attached to the gearbox. Monitoring the temperature inside the wind turbine gearbox helps to detect problems and fix them in time to prevent damage to the gearbox. Image source: Hongke Technology Co, Ltd
Ideal for remote monitoring: MSR385WD measuring system
with data logger and transmitter modules
The MSR385WD wireless data logger communicates with the MSR385SM wireless temperature transmitter module via the 868 MHz/915 MHz band mode, receives the measurement data and stores it. The data logger can communicate with 10 transmitters simultaneously to record and store the temperature of multiple points with a memory capacity of up to 1 million readings, making it ideal for long-term temperature recording. A flash memory ensures data security in the event of a power failure. The data logger is powered via the USB port; autonomous operation is possible for up to two days with the integrated 2400 mAh Li-Po battery. The MSR385WD has an extended Modbus RTU interface, which allows the data logger to be connected to the Profinet network via a gateway to enable online temperature monitoring in real time.
The MSR385SM transmitter module is equipped with a temperature sensor (-20...+125 °C), has one of the highest degrees of protection against water and dust with IP67 and has a maximum temperature resistance of 125 °C. Thanks to its robustness, the transmitter module is ideal for the complex and harsh working environment inside the wind turbine gearbox. Thanks to its extremely compact size (35 x 25 x 55 mm) and low weight (40 g), it can even be mounted in hard-to-reach areas of the gearbox.
Ideal for remote monitoring of temperature, humidity and air pressure: MSR385WD wireless data logger. The transmitter modules are available either in an ABS housing or in temperature-resistant (up to +125 °C) silicone tubing.
Architecture of the system for recording the gearbox temperature
The MSR385SM transmitter module installed in the wind turbine gearbox detects the temperature change and regularly sends the temperature signal to the MSR385WD data logger. The logger establishes a connection to the gateway device via the Modbus RTU interface. The peripheral Profinet master uses the Modbus communication protocol to obtain the temperature value of the logger via cable and remotely by accessing the register address. The temperature data is displayed in the upper computer. If the temperature exceeds the set value, an alarm can be set if required.
①MSR385SM transmitter module: Is installed in the gearbox. The high-precision temperature sensor detects the temperature change of the most important parts in the gearbox and transmits the measured data regularly via the 868MHz/915MHz radio band.
②MSR385WDdata logger: Installed outside the gearbox, receives the temperature data from the transmitter module, collects it, stores it and communicates with the communication module via the Modbus RTU interface.
③Profinet-to-RS485 gateway device: It is connected to the Modbus RTU interface of the MSR385WD data logger and uses the gateway conversion protocol to convert the Modbus data collected at the lower level into Profinet data, which is connected to the Profinet network as a slave station.
④Profinet master station: A controller, e.g. a PLC, acts as the master station.
⑤HMI,SCADA: HMI, SCADA: Display of temperature or other parameter data. It can be expanded with an oil pressure sensor and an ultrasonic sensor to create a more comprehensive system for inspecting and maintaining gearboxes.
Conclusion
Profinet, a new generation of industrial Ethernet technology, has strong anti-interference ability and high transmission speed, which solves the problem of real-time data transmission and stable transmission. The wind turbine gearbox temperature detection system based on the Profinet network integrates important temperature data inside the gearbox into the higher-level computer and visualizes it to provide timely understanding of the operating status of the gearbox, issue an early warning, save labor costs, and avoid major losses due to further deterioration of the fault. By analyzing the data later, maintenance recommendations can be made to extend the service life of the gearbox. The system also offers the following advantages:
Modular design: the gearbox, temperature detection device (MSR385SM transmitter module) and recording/storage device (MSR385WD data logger), gateway device (slave station), master station and higher-level computer software are independent of each other and can be replaced according to actual conditions.
Simple wiring: The front end of the system is simply wired via radio transmission. Profinet, the new generation of industrial Ethernet technology, connects the devices directly via the network cable, which simplifies the wiring process and reduces wiring and labor costs.
High degree of automation and low maintenance costs: the system automatically reads the temperature data, sets conditions for fault prediction and triggers alarms if necessary. The wireless temperature transmitter built into the gearbox is battery powered and has a battery life of up to 10 years, reducing maintenance time, costs and downtime.
High compatibility: Integrating the gearbox's temperature data into the Profinet network increases the system's upward compatibility, facilitates data management and analysis and enables accurate technical maintenance.