Development of a High-Precision Calorimeter for Measuring Power Loss in Electrical Machines

“…(Corresponding author: Armin Jafari, e-mail: armin.jafari@epfl.ch). Calorimetric methods have been used to directly determine losses from generated heat in power converters [8], [11], pulsed-power generators [12], motors and drives [13], [14], semiconductor devices and passive components [7], [15].…”

Section: Introductionmentioning

confidence: 99%

“…A balance test is performed with heaters to emulate the operation conditions of the main DUT to compensate for the variations in air properties. Furthermore, heat leakage through the chamber has to be minimized for high precision [13]. A double-chamber open-type calorimeter can mitigate the need for calibrations and balance tests [17].…”

Section: Introductionmentioning

confidence: 99%

High-Accuracy Calibration-Free Calorimeter for the Measurement of Low Power Losses

Jafari

Heijnemans

Soleimanzadeh

et al. 2021

IEEE Trans. Power Electron.

View full text Add to dashboard Cite

Wide-band-gap technologies enable ultra-high efficiencies in high-frequency power conversion. However, inadequate accuracies in electrical measurements could lead to spurious efficiency measurements, even above 100%. Furthermore, bandwidth limitations, particularly for current probing, delay mismatches between current and voltage probes, loading effects and electromagnetic interferences make electrical techniques inappropriate for measuring extremely-low losses in switches with high dv/dt and di/dt values and magnetic components with high-frequency excitations. Calorimetric methods overcome this issue by a direct loss measurement through the generated heat. Nevertheless, limited ranges and accuracies of existing systems hinder their application in sensitive measurements. Moreover, time-consuming calibrations with extensive data processing impede rapid design assessments. In this work, we propose a closed-type double-chamber calorimeter based on a real-time calibration between two identical chambers, to eliminate extra compensation for ambient variations or changes within the system itself. By streaming the same coolant in both chambers, our system removes the need for flow measurements, enabling extremely low flow rates which improves sensitivity and reduces complexity and system cost. The system provides adjustable cooling and can measure losses down to 500 mW, enabling the evaluation of highperformance power converters and their components with no dependencies on the geometries of the evaluated devices or systems.

show abstract

“…Calorimetric methods have been used to directly determine losses from generated heat in power converters [10], [13], pulsed-power generators [14], motors and drives [15], [16], semiconductor devices and passive components [9], [17]. In a calorimetric system, heat-transfer rate (P) to the coolant is determined by p (…”

Section: Introductionmentioning

confidence: 99%

Calibration-Free Calorimeter for Sensitive Loss Measurements: Case of High-Frequency Inductors

Jafari

Heijnemans

Soleimanzadeh

et al. 2020

2020 IEEE 21st Workshop on Control and Modeling for Power Electronics (COMPEL)

View full text Add to dashboard Cite

Wide-band-gap technologies enable ultra-high efficiencies in high-frequency power conversion. However, inadequate accuracies in electrical measurements could lead to spurious efficiency measurements, even above 100%. Furthermore, bandwidth limitations, particularly for current probing, delay mismatches between current and voltage probes, loading effects and electromagnetic interferences make electrical techniques inappropriate for measuring extremely-low losses in switches with high dv/dt and di/dt values and magnetic components with high-frequency excitations. Calorimetric methods overcome this issue by a direct loss measurement through the generated heat. Nevertheless, limited ranges and accuracies of existing systems hinder their application in sensitive measurements. Moreover, time-consuming calibrations with extensive data processing impede rapid design assessments. In this work, we further investigate a previously proposed closedtype double-chamber calorimeter and present its high accuracy for the evaluation of low levels of losses in high-frequency power inductors. The system provides adjustable cooling and can measure losses as low as 500 mW, enabling evaluation of highperformance power converters and their components with no dependencies on the geometries of the evaluated devices/systems.

show abstract

Development of a High-Precision Calorimeter for Measuring Power Loss in Electrical Machines

Cited by 40 publications

References 21 publications

Assessment of induction machine efficiency with comments on new standard IEC 60034-2-1

Assessment of induction machine efficiency with comments on new standard IEC 60034-2-1

High-Accuracy Calibration-Free Calorimeter for the Measurement of Low Power Losses

Calibration-Free Calorimeter for Sensitive Loss Measurements: Case of High-Frequency Inductors

Contact Info

Product

Resources

About