Correction of Winding Peak Temperature Detection in High-Frequency Automotive Electric Machines

Dong, Tenghui; Zhang, Xi; Zhou, Fei; Zhao, Baixuan

doi:10.1109/tie.2019.2931513

Cited by 8 publications

(15 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the slot winding part, Fig. 4 presents the cross‐section of slot winding and a typical arrangement of conductors [8, 19]. The AC loss factor K ac,slot of the l th layer winding wires can be calculated by (2) as a preliminary exploration [12, 20–22]

K_{ac, slot} = 1 + \frac{1}{4} {()(, \frac{\sum_{l - 1} N_{i}}{N_{l}})}^{2} {()(, \frac{ω μ_{0} d^{2} ε_{l}}{2 ρ_{0}})}^{2}

where N l is the number of wires in the l th winding layer, ω is the electrical angular velocity of the input current, μ 0 is the vacuum permeability, d is the diameter of the bare copper wire without surface insulation, ρ 0 is the electric resistivity of copper, ɛ l is defined as the fill factor of mental conductors to the slot

ε_{l} = N_{l} ()(, π d^{2} / 4) / ()(, w_{l} d)

where w l is the slot width at a depth of the l th layer.…”

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%

“…Equations (4) and (5) are proven to have enough accuracy in AC loss estimation for the slot and end winding parts in the alternating armature field [8, 19]. Besides, the rotation of the rotor will also cause additional AC loss in the winding [15].…”

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%

“…As the frequency increases higher than 300 Hz, the temperature rise in the active winding part will exceed that in the end winding part, producing detection error inevitably [8, 15].…”

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%

“…It is worth noting that for high‐power traction motors used in electric vehicles, the required monitoring accuracy of the temperature at hotspot is much more critical than the conventional industrial applications due to the potential transient high‐power output [8]. Inaccurate detection of the winding peak temperature may cause delayed actions of forced cooling and lead to thermal damages [2, 4, 9].…”

Section: Introductionmentioning

confidence: 99%

“…Taking the temperature of the end winding as the peak value inevitably causes detection errors, which misleads the thermal management system. Consequently, the thermal safety of the insulation system will be threatened by the underestimated temperature rise [2, 4, 8, 9].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Improved hotspot monitoring method for thermal management system of automotive traction motor

Dong

Zhang

Zhu

et al. 2020

IET Electric Power Applications

Self Cite

View full text Add to dashboard Cite

Hotspots in traction motors of electric vehicles are normally considered to locate in end windings due to the loose packaging and no access to iron cores for heat dissipation. To ensure safety, end winding temperatures are typically monitored by thermocouples in thermal management systems for real‐time cooling control. However, the authors’ study finds that slot winding temperatures will exceed end winding temperatures under high‐speed operations due to the much higher additional loss caused by the alternating flux. Hence, the thermocouple would underestimate the actual peak temperature in electric machines, causing insufficient cooling and potential damage to insulations. For cost savings, additional thermocouples monitoring slot winding temperatures are usually not equipped in the automotive industry. To calibrate the peak temperature of windings, this study proposes an innovative approach based on the thermo‐magnetic model of the traction motor, which provides the estimated slot winding temperatures only using the end winding sensors. As a result, the proposed method can provide much accurate peak temperatures for the thermal management system. Experimental tests validate the performance of the proposed method in improving the accuracy of hotspot monitoring.

show abstract

K_{ac, slot} = 1 + \frac{1}{4} {()(, \frac{\sum_{l - 1} N_{i}}{N_{l}})}^{2} {()(, \frac{ω μ_{0} d^{2} ε_{l}}{2 ρ_{0}})}^{2}

ε_{l} = N_{l} ()(, π d^{2} / 4) / ()(, w_{l} d)

where w l is the slot width at a depth of the l th layer.…”

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%

“…As the frequency increases higher than 300 Hz, the temperature rise in the active winding part will exceed that in the end winding part, producing detection error inevitably [8, 15].…”

Section: Movement Of Hotspots In the Windingmentioning

confidence: 99%