Electric Machine Baffle for Radial Cooling Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern electric vehicles face challenges in effectively cooling electric motor arrangements due to power losses resulting in high temperatures, which can lead to reduced power and potential failure of power electronics, and existing cooling methods compromise rotor bearing rigidity.
Innovation Solution
An electrical machine design featuring a stator, rotor, and inverter with a second end shield having cooling fins and a baffle plate that directs cooling air radially around the components, enhancing heat dissipation and maintaining rotor bearing rigidity through a compact, space-efficient design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If ventilation openings are provided for double-sided cooling, then cooling capacity is improved, but rotor bearing rigidity is reduced
Solution Approach 1:
The cooling system is segmented into separate inflow and outflow channels with distinct pathways. The baffle plate divides the cooling medium flow into separate channels, allowing independent optimization of cooling paths without compromising bearing structure integrity.
Solution Approach 2:
A baffle plate is introduced as an intermediary component to guide the cooling medium flow. This plate directs the cooling air from the intake opening through the stator and rotor regions to the exhaust opening without requiring ventilation openings in the bearing plates, thus maintaining bearing rigidity while achieving effective cooling.
2Temperature
If high-temperature air is used for cooling, then cooling of internal components is improved, but rotor bearing outer ring cannot be cooled and bearing wears out prematurely
Solution Approach 1:
Different regions of the bearing system receive different cooling conditions. The baffle plate configuration ensures that cooling air with appropriate temperature reaches the bearing outer ring region, while hotter air is directed toward internal components that require more aggressive cooling. This localized quality differentiation allows simultaneous protection of bearing reliability and effective cooling of internal components.
3Volume of moving object
If inverter is integrated in the second end shield with cooling fins, then compact design is achieved, but heat dissipation space is reduced
Solution Approach 1:
The inverter is mounted axially on the second end shield rather than occupying radial space. This axial arrangement utilizes the z-dimension (along the rotation axis) for inverter placement, freeing up radial space for cooling fins and maintaining effective heat dissipation surface area while achieving compact overall machine design.
Solution Approach 2:
The second end shield serves multiple functions: it provides structural support for the rotor bearing, acts as a mounting surface for the inverter, and serves as a base for cooling fins for heat dissipation. This multi-functionality allows compact integration of the inverter without compromising the heat dissipation capacity of the end shield structure.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design achieves effective cooling with high cooling capacity while maintaining the structural integrity of the rotor bearing, improving the reliability and service life of electronic components by optimizing heat exchange and reducing temperature stress.
Implementation Method 1
A baffle plate is arranged between the cooling fins of the second end shield and the stator and the rotor in such a way that a cooling medium flowing in radially through the at least one intake opening is guided to the at least one exhaust opening
Implementation Method 2
Cooling air is drawn in via the intake opening and guided along the cooling fins, with the cooling air being guided around the baffle and discharged via the outlet opening
Implementation Method 3
at least two cooling fins on the second end shield
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to an electric machine comprising a stator (1), a rotor (2) and an inverter (4) arranged in an inverter housing (3). Said rotor (2) is rotatably mounted about a rotational axis with its rotor axis in a first end shield (5) and in a second end shield (6). The second end shield is arranged in or on the inverter housing. At least one suction opening (7) and at least oneblowing opening (8) are arranged on the radial periphery of the second end shield (6). At least two cooling ribs (9) are provided on the second end shield (6), a baffle (10) is arranged between the cooling ribs (9) of the second end shield (6) and the stator (1) and the rotor (2) which is arranged in the stator (1), such that a cooling medium flowing radially through the at least one suction opening (7) is guided to the at least one blowing opening (8).