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19 ST/Industrial Sensing Solutions because transformers play a vital role in the reliability of a power system. Because of their essential part, the number of maintenance services should get kept to a minimum. Therefore, the condition monitoring of the transformers be- comes very crucial. The extensive volume data collected through sensors, such as an accelerometer can be used to develop models that predict potential failures in transform- ers. The accelerometer may get employed monitoring the windings and the core of a transformer. By using multiple accelerometers, it is possible to detect which winding should get repaired in case of a three-phase transformer. Anti-Tampering One of the critical components of Smart Grid is the smart meter. Over the last few years, the smart meters have advanced significantly thanks to cost-effective sensors. An accelerometer can be used in smart meters to determine if there has been any tampering. This may get performed by capturing the acceleration applied to the meter. By sensing the acceleration and comparing this value with a user-definable threshold in the dedicated registers of the sensor, it can then generate an interrupt signal that can be sent to a microcontroller for further processing and to create a notification of tampering. After the alteration has gotten identified, the proper measure can be taken to ensure an accurate meter reading. Shock Detection High-g accelerometers (full-scale range of ±400g) may get used measuring the duration and magnitude of impact or shock events within the high full-scale range. Typical applications for high-g accelerometers are shock detec- tion and asset monitoring. Accurate shock detection is vital in many applications, such as tracking the profile of the usage of leased assets, shipping data loggers, and the analysis of events caused by high-g shocks. Also, there are applications for the high-g accelerometers in military, crash detection, and sports. For example, with the informa- tion on the magnitude and direction of the shock, doctors can accurately diagnose concussion or head trauma resulting from accidents. Gyroscope The term Gyroscope gets applied to devices used to mea- sure angular rate along in-plane and out-of-plane axes. In dynamic conditions, the integration of the angular rate along the three axes allows determin- ing the three-dimensional angular orientation. There are several different technologies, which gyroscope development is based upon. We will briefly discuss a couple of the major ones in this article. Fiber Optic Gyroscope (Segnac Effect) offers high re- liability, but the cost of this type of device is high, and they are bulky. The traditional mechanical gyroscopes (Gyroscopic Effect) also have a few disadvantages namely high price, low reliability, and large size. Due to these factors, they are not suitable for many industri- al applications. The most exciting and innovative gyroscopes are the ones that are based on MEMS technology using different concepts. Quartz-based gyroscopes find deployment in non-standard packages and modular approach towards multi-axis gyroscopes is difficult. Piezo electric gyroscopes get characterized as having lower performance, and the assembly process is more time consuming and costly. These factors often make this type of gyroscope unsuitable for many industrial applications that require high perfor- mance and cost-effective solutions. The most efficient technology for high-performance and cost-effective gyroscopes are achieved using MEMS- based capacitive technology. They can be developed in very small size at high reliability at a very affordable cost because they may get produced in high volume with extremely high yield rate. They also have excellent stability over time and temperature. These advantages have made this type of gyroscopes an ideal candidate for many applications. MEMS gyroscopes getting discuss herein take advantage of the Coriolis Effect. The Coriolis Effect states that when an angular movement gets applied to a mass moving in direction x, the mass experiences a force in the direction perpendicular to the movement (Figure 2). In the structure in listed Figure 2, the resulting physical displacement is then processed using a capacitive sensing interface. Figure 1: Basic idea of a capacitive accelerometer. Figure 2: The principle of a MEMS gyroscope based on Coriolis effect.

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