Development of a wireless and self-sustaining sensor system in industrial applications for a high number of sensors

The industrial environment of a manufacturing plant is a suitable field of application for a variety of measuring tasks for process monitoring on the use of thermoelectric generators (TEG) for the power supply of wireless sensor modules. This paper describes the various aspects of the development of a self-sustaining system using the example of coolant monitoring and control. Subject is a continuous pressure and temperature measurement at each mold of a cooling system. Furthermore, wireless transmission of data to a central base station is required, wherein more than 50 sensor modules have to share one radio channel. The energy for operation of the sensor module is provided by a TEG using the temperature difference between the coolant tube and the "warm" environment. To attain a stable energy supply, various TEG and construction practices with controlled heat flow have been evaluated and optimized. In combination with a specific power management a robust, industry-compliant solution has been realized.