Integrated Vehicle Charger Using Traction Inverter and Motor Windings
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Solution Overview
Problem
Conventional external charger circuits for plug-in electric vehicles require additional dedicated components and are inefficient due to limited voltage control, leading to increased cost and weight, especially when charging with AC inputs.
Innovation Solution
A traction system with a DC bus, energy storage device, and a voltage converter assembly including phase legs and an electromechanical device, where a controller configures switches and phase legs to form DC/DC converters, enabling both bucking and boosting voltage without the need for significant on-board charger components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional external charger circuits with dedicated components are used, then battery charging capability is provided, but vehicle cost and weight increase
Solution Approach 1:
The patent combines the battery charging function with the existing traction motor and inverter components. The inverter is configured to operate as a charger by connecting the battery to the DC bus through the inverter switches, eliminating the need for separate dedicated charging components. This merging approach reduces vehicle weight while maintaining charging capability.
Solution Approach 2:
The inverter is designed to serve multiple functions: it acts as both a motor controller during vehicle operation and a battery charger during charging mode. By making the inverter universal, the patent eliminates dedicated charging components, thereby reducing vehicle weight without compromising charging functionality.
2Adaptability or versatility
If conventional external charger circuits with dedicated components are used, then battery charging capability is provided, but vehicle cost increases
Solution Approach 1:
The patent merges the charging function with existing inverter components, eliminating the need for separate dedicated charging components such as separate rectifiers, filters, and control circuits. This reduces the total component count and manufacturing cost while maintaining full charging capability.
Solution Approach 2:
The inverter is designed to perform both motor control and battery charging functions, making it a universal component. This multi-functionality reduces the overall system cost by eliminating redundant components and reducing assembly complexity.
3Adaptability or versatility
If voltage step down stage is added for AC charging, then charging compatibility is improved, but device complexity increases
Solution Approach 1:
The inverter is designed to handle both voltage step-down and voltage inversion functions. By making the inverter universal, the patent achieves charging compatibility across different AC voltage inputs without adding separate dedicated voltage conversion stages, thereby maintaining device simplicity.
Solution Approach 2:
The inverter switches are dynamically controlled to achieve both voltage step-down during charging and voltage inversion during motor operation. This dynamic control approach allows a single component to adapt to different operating conditions, eliminating the need for multiple static conversion stages.
4Productivity
If electromechanical device is disconnected during charging, then charging efficiency is improved, but device complexity increases
Solution Approach 1:
The inverter switches are dynamically controlled to direct current flow appropriately during charging mode. The same switches that connect the electromechanical device during motor operation are dynamically reconfigured to connect the battery to the DC bus for charging, eliminating the need for separate connection mechanisms while maintaining charging efficiency.
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 configuration allows for rapid charging without adding on-board charger components, reducing costs and space, while maintaining efficiency by keeping the electromechanical device connected to the converter assembly during charging.
Implementation Method 1
a phase leg and a winding of the electromechanical device form a DC/DC converter
Data Source
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AI summary
According to some embodiments, a traction system is disclosed. The traction system includes a DC bus (8), an energy storage device (4) coupled to the DC bus (8), and a voltage converter assembly (6,60,70) coupled to the energy storage device (4). The voltage converter assembly (6,60,70) includes a plurality of phase legs (22,23,24,25,26). The traction system further includes an electromechanical device (34,90,106) including a plurality of windings (35) coupled to the voltage converter assembly (6,60,70). The traction system also includes a switch (36,40) coupled to the DC bus (8) between the voltage converter assembly (6,60,70) and the energy storage device (4). The traction system includes a controller (42,124) configured to control the switch (36,40) and the voltage converter assembly (6,60,70) such that a phase leg and a winding of the electromechanical device (34,90,106) form a DC/DC converter.