Smart in-cylinder pressure sensor for closed-loop combustion control

Our approach of a closed-loop combustion control is built on an intensively evaluated robust cylinder pressure sensor with integrated smart electronics and an openly programmed engine control unit. The presented pressure sensor consists of a steel membrane and a highly strain-sensitive thin film with laser-welded electrical contacts. All components are optimized for reliable operation at high temperatures. The sensor setup safely converts the in-cylinder pressure of a combustion engine at temperatures of up to 200 ∘C into the desired electrical values. Furthermore, the embedded smart electronics provides a fast analogue to digital conversion and subsequently computes significant combustion parameters in real time, based on implemented thermodynamic equations, namely the 50 % mass fraction burned, the indicated mean effective pressure, the maximum pressure and a digital value, which represents the intensity of knocking. Only these aggregated parameters – not the running pressure values – are sent to the engine control unit. The data communication between the smart sensor and the engine control unit is based on the controller area network bus system, which is widely spread in the automotive industry and allows a robust data transfer minimizing electrical interferences. The established closed-loop combustion control is able to control the ignition angle in accordance with the 50 % mass fraction burned at a certain crankshaft angle. With this loop, the combustion engine is controlled and run efficiently even if the ignition angle is intentionally incorrectly adjusted. The controlled and automatic correction of simulated ageing effects is demonstrated as well as the self-adjustment of an efficient operation when different fuels are used. In addition, our approach saves the computing capacity of the engine control unit by outsourcing the data processing to the sensor system.

Is it possible to turn a diesel engine into a less pollutant device?

The current tendency in the eastern part of Europe is to modify old diesel engines with the purpose of improving characteristics in terms of horsepower and torque, but also to reduce the generated pollution. The diesel engines are still in use, against to the tendencies of renouncing to their support, at least in larger urban & industrial areas, where the pollution level, especially the particulate matter (particles PM10, PM2.5) and ozone concentrations, also the NOx are supposed to be generated mostly by diesel engine vehicles. The paper presents results concerning the influence of modifying the diesel engine control unit’s parameters, such as injection quantity, start of injection, intake air pressure and all the others correlated for better performance. The article brings into attention possibilities to reduce the exhaust pollution concentrations, correlated by simultaneous ways of improving the external characteristics of the engine by modifying the engine control unit’s parameters. Measurement results of a compression ignited internal combustion engine before and after the retrofitting, by reparametrization, meaning changing the parameters are presented and discussed.

PEMBUATAN ALAT TPS (THROTTLE POSITION SENSOR) CHECKER PADA SEPEDA MOTOR HONDA REVO PGM-FI BERBASIS IOT MENGGUNAKAN MODUL ESP32

Berkembangnya teknologi membuat mesin kendaraan sekarang menggunakan sistem injeksi yang dilengkapi dengan berbagai komponen dan sensor untuk mendukung proses pembakaran di ruang mesin. Salah satunya yaitu TPS (Throttle Position Sensor). Sensor TP berfungsi untuk mendeteksi adanya perubahan posisi pada throttle gas. Adanya kerusakan pada sensor TP dapat mempengaruhi performa dari kendaraan. Umumnya pengecekan sensor TP dilakukan menggunakan multimeter yang tentunya sulit untuk dilakukan, karena posisi dari sensor TP yang sulit dijangkau. Maka dari itu dibutuhkan alat yang mampu digunakan untuk mengecek kondisi sensor TP secara efisien. TPS Checker merupakan alat yang digunakan untuk mengecek kondisi sensor TP melalui pengukuran tegangan pada input dan output sensor TP serta hambatannya sesuai dengan kondisi bukaan throttle gas. Hasil pengukuran didapat dari rumus pembagi tegangan (voltage divider). Alat TPS checker dibuat dengan menggunakan microcontroller ESP32 yang dapat dihubungkan dengan smartphone untuk menampilkan hasil pengukuran secara real-time melalui aplikasi Blynk serta dilengkapi fitur reset untuk menghapus data kerusakan yang sudah terdeteksi dan tersimpan di Engine Control Unit (ECU). TPS Checker dapat digunakan untuk mengukur sensor TP pada seluruh kendaraan injeksi, namun penulis melakukan pengujian TPS Checker menggunakan sepeda motor Honda Revo PGM-FI. Setiap tipe kendaraan memiliki standar pengukuran yang berbeda-beda. Standar pengukuran pada motor Honda Revo PGM-FI yaitu tegangan sensor TP sebesar 4,75V – 5,25V dan hambatan berada pada rentang 0 – 5K Ohm. Dari hasil pengujian TPS Checker dapat disimpulkan bahwa alat ini mampu digunakan untuk melakukan pengukuran pada sensor TP serta menghapus kode kerusakan pada sepeda motor Honda Revo PGM-FI.

Special Issue “Technologies for Future Distributed Engine Control Systems”

Current trends in aviation greatly expand the use of highly integrated, increasingly autonomous air vehicles, with distributed engine control systems (DECS) [...]

Research on the civil aero-engine modeling method oriented to control law design

The non-linear aero-thermal model of civil aero-engine established by the component method has the characteristics of complex structure and strong coupling of parameters, which is difficult to directly use in the design of control law. Aiming at the problem that civil aero-engine control law design is difficult, heavy workload, and can only be used for nominal point linearization model, a civil aero-engine modeling method oriented to control law design is proposed. Simplify the structure according to the aero-engine control function, and use rotor dynamics modeling and combustion reaction dynamics modeling to establish aero-engine control standard model in differential form, which establishes the corresponding relationship of the parameters required for the control of the aero-engine full envelope. With this control standard model, the nonlinear control method can be directly used in the design of the aero-engine control law, which reduces the workload and difficulty of the control law design to certain extent. The control standard model is established by taking DGEN380 aero-engine as an example, whose accuracy is verified through experiments, and an example of the control law design is given. The civil aviation engine modeling method oriented to control law design has achieved the expected goal.