Differential pressure sensor series, fighting to protect blue skies

With the improvement of people's living standards and the rapid development of the automobile industry, the number of motor vehicles in my country continues to rise. According to statistics from the Ministry of Public Security, the number of motor vehicles in China reached 395 million in 2021, ranking first in the world in both total volume and increase. While facilitating people's daily lives, vehicles, as a mobile source of pollution, have caused a huge burden on the ecological environment due to their exhaust emissions. For this reason, the country has introduced strict National VI emission standards, requiring more measures to reduce harmful components in vehicle exhaust emissions, such as the installation of exhaust after-treatment systems. The performance of the exhaust after-treatment system depends to a large extent on the sensors used in conjunction with it. Sensors are also necessary hardware for the OBD on-board diagnostic system that meets the requirements of the National VI regulations for the after-treatment system. Among them, the differential pressure sensor series is the most commonly used sensor, and their contributions to environmental protection cannot be ignored.

Sensata Technologies Differential Pressure Sensor

When it comes to the differential pressure sensor series, we have to mention Sensata Technologies, which is one of the world's leading independent sensor manufacturers. The differential pressure sensor series developed and manufactured by Sensata Technologies is based on MEMS micro-electromechanical technology and is built on a strong technical reserve and rich technical experience. The purpose of the particulate filter in the exhaust after-treatment system is to reduce the emission of particulate matter to meet the requirements of the National VI emission regulations. The main functions of the differential pressure sensor are: first, it is used to monitor the pressure difference between the upstream and downstream of the particulate filter, and to determine whether the particulate filter is blocked or leaking through the differential pressure signal; second, after the soot amount of the particulate filter reaches the upper limit, the particulate filter is regenerated and controlled through the differential pressure signal; third, the particulate filter is diagnosed for excessive emissions. In addition, the diagnostic demand for the detachment of the rear-end pipeline of the particulate filter is added in the exhaust after-treatment of gasoline engines. At this time, a dual-mode differential pressure sensor is needed. In addition to the main functions of the differential pressure sensor mentioned above, it can also measure the pressure of the rear-end pipeline of the particulate filter. The significant advantages of differential pressure sensors and dual-mode differential pressure sensors include high exhaust tolerance, high reliability, high accuracy and anti-icing. The selection of differential pressure sensors and dual-mode differential pressure sensors mainly considers the pressure range, operating temperature, output signal form, pull-up and pull-down resistors and accuracy. The selection of dual-mode differential pressure sensors also needs to consider the selection of the pressure range of the rear-end pipeline of the particle trap. Different shapes of differential pressure sensors and dual-mode differential pressure sensors are available according to the installation requirements of different customers, such as the number of bolt holes, the diameter of the pressure port and the connector model.

Sensata Technologies Dual Mode Differential Pressure Sensor

The diesel engine EGR system uses a venturi flowmeter to achieve precise control of the EGR flow, and the flowmeter calculates the flow by measuring the exhaust pressure at one end of the venturi tube and the pressure difference at both ends of the thermometer. The common mode pressure inside the venturi tube can reach more than 5barG, while the pressure difference at both ends of the venturi tube is only about 35kpa. Therefore, a high common mode differential pressure sensor was born. It is a differential pressure sensor that has high common mode pressure and can measure a small range of differential pressure. The design advantages of the high common mode differential pressure sensor are excellent exhaust gas tolerance, common mode pressure tolerance higher than 5barG, high accuracy and anti-icing. Similar to the differential pressure sensor and dual-mode differential pressure sensor mentioned above, the high common mode differential pressure sensor mainly considers the five factors of pressure range, operating temperature, output signal format, pull-up and pull-down resistors and accuracy during the selection process.

Sensata Technologies High Common Mode Differential Pressure Sensor

In addition to the differential pressure sensor series, Sensata Technologies also has many other products that have made great contributions to the protection of the ecological environment. For more product information, please visit Sensata Technologies' website: www.sensata.com.cn, or follow the WeChat public account: SensataChina.