Bypass Circuit for Automotive Power Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automotive electrical systems face challenges in providing low-power connections when main high-current paths are disabled, particularly in preventing short-circuit and high-current conditions without consuming excessive power, as mechanical relays degrade over time and have limited lifespans.
Innovation Solution
A bypass circuit comprising a current limiter and a comparator that provides an auxiliary low-current path when the main path is disabled, detecting excessive current through a voltage drop comparison with a reference voltage, enabling corrective actions such as disabling the current limiter or switching back to the main path.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If mechanical relays are used to provide high-current paths, then high power levels can be delivered to electrical loads, but the relays consume relatively high power levels themselves and have limited lifespan due to contact wear
Solution Approach 1:
The patent replaces mechanical relays with solid-state electronic switches (MOSFETs or IGBTs) that have no moving parts or contacts. These semiconductor devices can handle high current levels without contact wear, eliminating the lifespan limitation while maintaining the high power delivery capability. The solid-state switches are controlled by gate signals and can be integrated with protection circuitry to provide reliable high-current paths indefinitely.
Solution Approach 2:
The patent introduces solid-state power switches as intermediary devices between the power source and electrical loads. These switches act as electronic mediators that can handle high current without the mechanical contact wear problems of relays. The switches are配合 with control circuitry and protection mechanisms to provide reliable high-power transmission while extending system lifespan.
2Loss of energy
If main current paths are disabled during low-power modes, then power consumption is reduced, but the system loses ability to provide current to electrical loads when needed
Solution Approach 1:
The patent implements dynamic power management where solid-state switches can be rapidly enabled or disabled based on system power mode requirements. During low-power modes, the main current path switches remain disabled to minimize consumption, but the bypass circuit switches are enabled to provide minimal current for essential functions. The system can dynamically transition between these states without mechanical wear, maintaining operational flexibility while optimizing power consumption.
Solution Approach 2:
The patent segments the current path into multiple parallel routes: a main current path for high-power operation and a bypass current path for low-power operation. This segmentation allows the system to selectively activate appropriate paths based on power mode requirements. The bypass path includes solid-state switches that can provide essential current during low-power modes without the limitations of mechanical relays, ensuring continuous operational capability.
3Productivity
If mechanical relays are used for switching, then current can be switched to high-power systems, but the contacts degrade over time leading to limited operational lifespan
Solution Approach 1:
The patent replaces mechanical relay contacts with solid-state power switches (MOSFETs or IGBTs) that have no physical contacts to wear. These semiconductor devices switch current electronically through field-effect control, eliminating contact degradation entirely. The solid-state switches can perform millions of switching cycles without performance degradation, maintaining full current switching capability throughout the vehicle's operational life and beyond.
4Ease of operation
If high-current paths are always available, then electrical loads can be powered immediately, but power consumption increases during low-power modes
Solution Approach 1:
The patent implements dynamic control of parallel current paths using solid-state switches. The main current path switches are disabled during low-power modes to minimize consumption, while bypass circuit switches remain enabled to provide essential current. When high power is needed, the main path switches are rapidly enabled. This dynamic switching capability, enabled by solid-state devices, allows the system to optimize power consumption while maintaining operational readiness.
Solution Approach 2:
The patent segments the power delivery system into main current paths and bypass current paths with separate solid-state switch control. This segmentation enables independent control of each path based on power mode requirements. During low-power modes, only the bypass path is active providing minimal essential current. When high power is required, the main paths are activated. This segmented architecture with solid-state switching eliminates the need to keep all paths continuously active, reducing power consumption while maintaining power availability.
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 bypass circuit effectively protects electrical systems from short-circuits and high-current faults, reduces power consumption during low-power modes, and extends the lifespan of the system by automatically addressing transient faults without human intervention.
Implementation Method 1
The current limiter is configured to provide an auxiliary current path between a power supply line and an electrical load when a main current path between the electrical load and the power supply line is disabled
Implementation Method 2
The comparator is configured to compare a voltage drop across the current limiter with a reference voltage, and to output a detection signal responsive to the voltage drop exceeding the reference voltage
Data Source
AI summary
Circuits, systems and methods are provided wherein a bypass circuit provides an auxiliary current path to supply current from a power supply line to an electrical load. The bypass circuit is used during a low-power mode, and consumes less quiescent power than a main current path that provides current from the power supply line to the electrical load during normal operation. The bypass circuit includes a current limiter and a comparator, and generates a high-current detection signal responsive to the comparator detecting that a current through the current limiter exceeds a maximum allowed or expected current.