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Gallium Nitride (GaN) high electron mobility transistor (HEMT) is one of the promising candidates to replace existing switches in high-frequency high power converter applications. Reliability of GaN HEMT is an important issue for its commercial deployment. Online prognosis of this transistor ensures robust reliability for mission critical applications. Online prognosis requires identification of fault...
Torque production capability of permanent magnet synchronous machines (PMSMs) depends on the permanent magnets (PM) magnetization state (MS). MS is a function of PM initial magnetization level, decreasing as temperature increases. Furthermore, excessive PM temperature can produce irreversible PM demagnetization. PM MS and temperature measurement/estimation is therefore important both for torque control...
This paper proposes a method to estimate the stator winding temperature of permanent magnet synchronous motor (PMSM) driven by direct torque control (DTC) strategy, where the stator resistance is used as a direct indicator of the temperature. In this method, the quantitative relationship between the dc current offset and the corresponding changes in torque is derived. The dc current offset is generated...
In this paper an Extended Kalman Filter (EKF) is used as an observer for temperature monitoring, like a virtual sensor, of a metal-polymer fibre based heater structure. Metal-coated polymers are relevant for the realisation of smart systems (capable of both sensing and actuating). A real-time implementation of the temperature estimator is important to guarantee a gentle, fault-free operation of the...
Thermal monitoring is a common feature in most of electric machine drives since thermal overloading is one of the most common causes of motor failures. Contact-type sensors are normally used to measure the stator temperature in electric machines. However, use of this type of sensor is not advisable in the rotor as it requires cabling to a rotating part or the use of a wireless transmission system...
Energy Storage System (ESS), with its fast ramping and bi-direction power flow capabilities, is playing a more vital role in the electric market. However, it still stands on the farther end of economic viability. As a result, a good estimate of battery service life, and therefore revenue, is necessary before the investment is made in any given application. In this paper, a set of improved degradation...
This paper presents a novel algorithm for in situ efficiency estimation for induction motors operating with distorted unbalanced voltages. The proposed technique utilizes the genetic algorithm, IEEE Form F2-Method F1 calculations, large motor test database and a new stray-load loss formula. The technique is evaluated by testing 3 small- and medium-sized induction motors with 11 different combinations...
An accurate estimation method of State of Health (SOH) for lithium battery is presented in this paper. The battery model is improved based on equivalent circuit model and battery internal electrochemical characteristics. In our study, Double Unscented Kalman Filtering (D-UKF) algorithm is designed to calculate State of Charge (SOC) and SOH at the same time. The main feature is the battery SOH estimation...
Photovoltaic (PV) modeling plays a vital role in the estimation of the expected yield from a PV generation plant. The single diode model of a PV module requires estimation of 5 unknown parameters derived from the equivalent circuit using only the parameters extracted from datasheets as input. These parameters are used to evaluate the current and voltage from the module under varying conditions of...
The paper addresses the problem of Dynamic Line Rating (DLR) estimation for OverHead transmission Lines (OHLs) in the context of Wide Area Monitoring Systems (WAMSs). DLR is universally recognized by experts from academia and industry as one of the most viable solution for a reliable exploitation of the real power systems thermal loadability margins. In this domain, the large quantity of synchronized...
A simple approach of sensorless junction temperature estimation is proposed for SiC power MOSFET devices. The junction temperature is derived in real-time by finding the instantaneous on-state resistance which is temperature sensitive and can be used as an indicator for device thermal estimation. Based on the scheme, a high-speed circuit is designed to quickly detect the on-state resistance and estimate...
This paper proposes alternative methods for the estimation of the phase winding- and magnet temperature of a surface mounted permanent magnet synchronous machine. Different approaches for HF injection based temperature estimation are discussed and analysed. The conclusion for HF techniques leads to the design of a recursive least squares base estimation approach which with good properties regarding...
The injection of a high frequency signal in the stator via inverter has been shown to be a viable option to estimate the magnet temperature in PMSMs. The variation of the magnet resistance with temperature is reflected in the stator high frequency resistance, which can be measured from the resulting current when a high frequency voltage is injected. However, this method is sensitive to d and q-axis...
Battery is the major energy storage source of electric vehicles (EVs), which makes the accurate estimation of State-of-Charge (SOC) very crucial. Various SOC estimation methods have been proposed in recent years. Among of them, Ah method is widely used due to its easy implementation. This paper presents an energy method for SOC estimation of power lithium-ion battery, which is based on the law of...
This paper investigates a new approach based on the fuzzy logic-controlled methodology that is suitable for analyzing and evaluating large format LiMn2O4 cell performance via online state-of-health (SOH) prediction for energy storage system (ESS) applications. The proposed method for online SOH prediction is comprised of two parts. First of all, the values of the cell resistance R and maximum cell...
There are well-defined methods to measure the (increased) series resistance of PV panels in controlled laboratory conditions. However, the presence of various irradiance levels and partial shadows, in case of an outdoor installation, may affect the series resistance estimation. This paper focuses on the estimation of increased series resistance in outdoor conditions in various irradiance levels and...
In this paper, a detailed study of the performance of rotor flux and reactive power based MRAS rotor resistance estimators for Vector Controlled Induction Motor drive is presented. The rotor resistance changes significantly during operation of the drive due to temperature rise and saturation. This variation has a major influence on the performance of the field oriented control of induction motor drive...
This paper puts forward a framework for estimating transmission line parameters (including series resistance, reactance and shunt susceptance), line temperature and sag utilizing synchronous voltage and current phasors measured by the phasor measurement unit (PMU) in real time. Transmission line parameters are essential inputs to various power system analyses and applications such as power flow analyses...
In this paper, an effective approach for estimating the operating temperature of a photovoltaic (PV) module is presented. The developed method is simple and does not need any additional hardware. The proposed approach uses an analytical formula to derive the temperature from the maximum power point (MPP) voltage and current. The effectiveness of the new method is investigated through some conducted...
It is well-known that the slope of the I-V curve of a photovoltaic panel at open-circuit conditions is proportional to the panel's internal series resistance. However, the slope of the I-V characteristic is greatly affected by environmental conditions, showing an approximately linear relationship with the reciprocal of the irradiation. In this work, a simple series resistance estimation method based...
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