Sensorless rotor temperature estimation of permanent magnet synchronous motor

Abstract

The work proposes a method for estimation of the magnet temperature in permanent-magnet synchronous machines by exploiting the d-axis saturation effects in the steel stator core produced by the d-current and rotor flux excitation. The method implies an intermittent injection of a voltage pulse in the d-axis of the motor. The resulting d-current response is a function of both the initial value of the d-current itself and the magnetization level of the magnets. Thus, a temperature dependent variation in the magnetization level of the permanent magnets is reflected in a variation of the d-current slope upon the voltage pulse. Experimental validation of the method is demonstrated with surface permanent-magnet motor.Index Terms-magnet temperature, rotor temperature, permanent-magnet synchronous motor, saturation effects, voltage pulse injection I.978-1-61284-972-0/11/$26.00

Permanent Magnet Temperature Estimation in PM Synchronous Motors Using Low-Cost Hall Effect Sensors

“…Furthermore, knowledge of the machine inductances is needed, which can significantly change with the operating condition of the machine [18]- [21]. Finally signal injection methods require injection of an additional high frequency signal superimposed on the fundamental excitation [7]- [13]. While these methods can operate at any speed, including zero speed, they can have some adverse effects on the operation of the machine (e.g.…”

“…Temperature estimation reported in the literature include thermal model based methods [3]- [6], back electromotive force (BEMF) based methods [15]- [21] and methods based on the injection of some form of test signal [7]- [13]. Thermal models require precise knowledge of the machine geometry, materials and cooling system for obtaining a precise model for each machine design [3]- [6].…”

“…Contact-type temperature sensors such as thermistors or 1 This work was supported in part by the Regional Ministry of Education, Culture and Sport of the Principality of Asturias through "Severo Ochoa Program" under Grant BP-13067, and in part by the "Human Resources program in Energy Technology" of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20154030200610) thermocouples would require cabling to a rotating part through slip rings and brushes, or the use of a wireless transmission system [9], [10], [12]- [13]. Alternatively, non-contact sensors, i.e.…”

Energy harvesting and wireless data transmission system for rotor instrumentation in electrical machines

“…Instrumentation to measure rotor temperatures in electrical machines has been reported in the literature as part of thermal modelling studies or the verification of sensorless temperature estimators and observers [5,6,7,8]. In all cases, those systems were battery powered and transmitted data wirelessly using infrared (IR) communication [5,6].…”

“…In all cases, those systems were battery powered and transmitted data wirelessly using infrared (IR) communication [5,6]. The authors in [9] used an isolated DC/DC converter IC connected to the synchronous machine excitation to feed temperature sensors and a Bluetooth data transmission system.…”