Capacitor Block With Integrated LC Filter For 48V Power Modules
Solution Overview
Problem
Existing capacitor blocks for motor vehicle power modules face challenges in withstanding high temperatures, corrosive atmospheres, and fluid exposure, while also needing to reduce electromagnetic interference and salt bridge formation, especially when integrated with alternator-starters operating at higher voltages like 48 V, which conventional solutions such as LC-type differential filtering and toroid inductors are not compatible with.
Innovation Solution
A capacitor block design featuring a metal tank with cooling fins, filled with a thermally conductive and electrically insulating material, incorporating bar buses of positive and negative polarity connected via insulating supports, with integrated LC-type differential filters using the bar buses as differential inductors, and surrounded by magnetic plates for improved heat dissipation and interference reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If conventional LC-type differential filtering with toroid inductors is used, then electromagnetic interference is reduced, but the device is not compatible with high-voltage alternator-starters and cannot withstand harsh under-hood conditions
Solution Approach 1:
The patent changes the voltage rating parameter from conventional low voltage to high voltage (48V system), and modifies the thermal and chemical resistance parameters to withstand under-hood conditions. The capacitor block uses high-voltage rated capacitors and heat-resistant materials, transforming the device parameters to be compatible with alternator-starters while maintaining EMI filtering capability.
Solution Approach 2:
The patent employs composite construction combining multiple materials with complementary properties: heat-resistant epoxy resin encapsulation, corrosion-resistant metal busbars, and EMI-shielding materials. This composite approach enables simultaneous achievement of high-voltage compatibility, thermal resistance, and electromagnetic interference reduction.
2Volume of moving object
If the capacitor block is integrated with the inverter on the rear bearing, then space is saved, but the device must withstand high temperature, corrosive atmosphere, and fluid exposure
Solution Approach 1:
The patent uses a protective encapsulation shell made of heat-resistant epoxy resin that seals the capacitor block, providing protection against corrosion, fluids, and high temperature while maintaining a compact integrated form factor suitable for mounting on the alternator-starter rear bearing.
Solution Approach 2:
The patent employs inexpensive protective coatings and sealants that provide reliable protection against harsh under-hood conditions. The design uses cost-effective materials like epoxy resin encapsulation and corrosion-resistant plating that ensure long-term reliability in high-temperature and corrosive environments.
3Power
If high current applications are used with alternator-starters, then power is increased, but conventional printed circuit board tracks cannot handle the current
Solution Approach 1:
The patent extracts the high-current conduction function from the printed circuit board and implements it through separate heavy-gauge metal busbars. These dedicated current-carrying elements are taken out from the conventional PCB structure, allowing high current flow without overheating while the PCB handles only control and low-power signals.
4Use of energy by moving object
If voltage levels are increased to 48V to improve efficiency, then power consumption is reduced, but the electrical network architecture becomes more complex
Solution Approach 1:
The patent designs the capacitor block to serve multiple functions simultaneously: voltage stabilization for the 48V high-voltage network, EMI filtering for both high-voltage and 12V networks, and energy storage for power quality improvement. This multi-functionality reduces the need for separate components, simplifying the overall electrical network architecture despite the dual-voltage system.
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
The solution effectively stabilizes voltage, reduces electromagnetic interference, and withstands harsh conditions like high temperatures and corrosive environments, ensuring compatibility with high-voltage alternator-starters and maintaining interference levels within regulatory limits.
Implementation Method 1
partially filled with a thermally conductive and electrically insulating material
Implementation Method 2
partially filled with a thermally conductive and electrically insulating material
Implementation Method 3
This tank is equipped on the outside with cooling fins
Implementation Method 4
This tank is equipped on the outside with cooling fins
Implementation Method 5
The assembly device comprises a bar bus of positive polarity and a bar bus of negative polarity
Implementation Method 6
held on each other without electrical contact by means of an insulating support
Implementation Method 7
integrated LC-type differential filters using the bar buses as differential inductors
Implementation Method 8
integrated LC-type differential filters using the bar buses as differential inductors
Implementation Method 9
surrounded by magnetic plates for improved heat dissipation and interference reduction
Data Source
Figure 1~2b
Figure 3~4
Figure 5~6
AI summary
The invention relates to a bank of capacitors for an automotive vehicle electronic power module of the type of those comprising a plurality of capacitors (17, 42), a busbar of positive polarity (25) and a busbar of negative polarity (26) which are held one above the other without electrical contact by means of an insulating support (39) and which are intended respectively to be connected electrically to a positive terminal (HV+) and to a negative terminal (HV-) of said electronic power module, said busbar of positive polarity (25) and said busbar of negative polarity (26) respectively comprising a positive plate for assembly (31, 32) with the capacitors (17, 42) and a negative plate for assembly (33, 34) with the capacitors (17, 42), characterized in that it comprises a differential filter of LC type integrated into said bank of capacitors and able to be connected to an on-board network of said automotive vehicle.