MOS-FET as a Current Sensor in Power Electronics Converters

Sensors

Rok Pajer¹  Miro Milanoviĉ¹  Miran Rodiĉ¹  Branko Premzel² 

[1] Faculty of Electrical engineering and computer sciences, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia;Piktronik, Cesta k Tamu 17, SI-2000 Maribor, Slovenia;

关键词: power electronics;    converter;    MOS-FET;    current measurement;    thermal model;   

DOI  :  10.3390/s150818061

来源: DOAJ

【 摘 要 】

This paper presents a current sensing principle appropriate for use in power electronics’ converters. This current measurement principle has been developed for metal oxide semiconductor field effect transistor (MOS-FET) and is based on UDS voltage measurement. In practice, shunt resistors and Hall effect sensors are usually used for these purposes, but the presented principle has many advantages. There is no need for additional circuit elements within high current paths, causing parasitic inductances and increased production complexity. The temperature dependence of MOS-FETs conductive resistance RDS−ON is considered in order to achieve the appropriate measurement accuracy. The “MOS-FET sensor” is also accompanied by a signal acquisition electronics circuit with an appropriate frequency bandwidth. The obtained analogue signal is therefore interposed to an A-D converter for further data acquisition. In order to achieve sufficient accuracy, a temperature compensation and appropriate approximation is used (RDS−ON = RDS−ON(Vj)). The MOS-FET sensor is calibrated according to a reference sensor based on the Hall-effect principle. The program algorithm is executed on 32-bit ARM M4 MCU, STM32F407.

【 授权许可】

Unknown