Improvement of the cooling performance of symmetrically self-ventilated induction machines in the 2-15 MW range

Abstract

This paper presents the results of an effort to improve the cooling performance of symmetrically self-ventilated induction machines in the 2-15 MW Range. Aerodynamic modifications are applied to the rotor inlet, the rotor bars, the stator bars and the stator cooling gap supports. The modificatiorts are tested in a rotating test r i g under labomtory conditions and in a prototype engine. The cooling mass flow and cooling eficiency are increased by more than 10%.

Cooling of Automotive Traction Motors: Schemes, Examples, and Computation Methods

“…The cooling performance of the forced air motors strongly depends on how large the surface contact areas is between the coolant and the motor components. This can be improved by adding geometrical modification such as cutting multiple air slots into the shaft, rotor, or the stator core [36].…”

“…In this paper, a detailed analysis of the active type cooling: the natural [21][22][23][24][25][26][27][28], forced air [29][30][31][32][33][34][35][36][37][38][39][40][41][42], forced liquid and phase change types [18,[66][67][68], are reviewed in Section II. On this basis, a comprehensive summary of the convection methods as applicable to the automotive traction motors cooling contexts have been provided with the advantages and disadvantages of each method being compared.…”

Electrical Machine Slot Thermal Condition Effects on Back-Iron Extension Thermal Benefits

“…In transportation applications, water-jacket cooling is commonly applied to electrical machines due to the compact volume of liquid cooling with respect to forced-air cooling, with the latter requiring more space for auxiliaries such as fans and coolers [4][5][6][7]. For a conventional assembled water jacket which encloses the stator core, the heat generated within the slot is eventually removed to the coolant via the slot, the back-iron and housing [6,[8][9][10][11][12][13].…”

Equivalent Slot Thermal Conductivity and Back-iron Extension Effects on Machine Cooling

“…Compared to air forced cooling [4], liquid cooling provides a more efficient cooling system. For a conventional water jacket cooling system [5][6][7][8][9][10][11], where the stator core is enclosed by the housing that carries water, the heat generated in the slot are dissipated to the water jacket, via slot, slot liner, back-iron and housing.…”