Switchable Ground Overvoltage Protector for Automotive Voltage Spikes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Voltage spikes in motor vehicle electrical systems can damage sensitive consumers like sensors in exhaust gas treatment systems, and existing solutions are inadequate for effective protection.
Innovation Solution
An overvoltage protector with a potential input and output, a ground terminal connected via a line with a blocking component and a switch controlled by a circuit, where the switch closes during voltage spikes to divert excess current, using a component like a zener diode to reduce voltage and ensure stable supply to sensitive consumers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a ground connection is provided to divert current during voltage spikes, then protection against voltage spikes is improved, but the voltage at the potential output is reduced even during normal operation
Solution Approach 1:
The patent applies a switchable ground connection that can be dynamically opened or closed based on voltage conditions. The control circuit monitors the voltage and closes the switch only when a voltage spike is detected, allowing the ground connection to divert current during spikes while keeping it open during normal operation to maintain proper voltage levels at the potential output.
Solution Approach 2:
The control circuit implements feedback by continuously monitoring the voltage at the potential input and potential output terminals. When a voltage spike is detected (voltage exceeds threshold), the control circuit activates the switch to close the ground connection. Once the voltage returns to normal, the switch opens again, creating a closed-loop protection system that responds to actual voltage conditions.
2Stability of the object's composition
If a blocking component is used to maintain voltage during normal operation, then voltage stability is improved, but the component may be damaged by sustained high voltage operation
Solution Approach 1:
The blocking component (such as a Zener diode or varistor) is subjected to periodic rather than continuous high-voltage stress. The control circuit closes the switch only during brief voltage spike events, allowing the blocking component to conduct and stabilize voltage during these short intervals while remaining inactive during normal operation, thereby preventing thermal damage from sustained operation.
Solution Approach 2:
The control circuit acts as an intermediary between the blocking component and the voltage spike. Instead of allowing the blocking component to directly handle all voltage variations, the control circuit monitors conditions and selectively activates the component only when necessary, protecting it from sustained high-voltage exposure while still providing voltage stabilization during spikes.
3Reliability
If the switch is kept closed to provide continuous protection, then protection effectiveness is improved, but voltage is reduced to zero at the potential output
Solution Approach 1:
The switch is designed to be dynamic rather than static, transitioning between open and closed states based on real-time voltage conditions. During normal operation, the switch remains open to allow full voltage supply to the consumer. When a voltage spike occurs, the switch closes briefly to divert the spike current through the ground connection, then opens again once the spike subsides, maintaining both protection effectiveness and proper voltage supply.
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 reliably provides a stable 12 V supply to sensitive consumers while protecting against voltage spikes, ensuring the component is not damaged by sustained operation and maintaining voltage at a desired level during spikes.
Implementation Method 1
voltage is present at the potential output of the overvoltage protector even when the switch is closed since a component that blocks below a threshold voltage and conducts above the threshold voltage is located in the line leading to the ground output. Such a component can be e.g. a varistor or a diode, in particular a zener diode
Data Source
AI summary
An overvoltage protector for an electrical consumer in a motor vehicle, includes an input for connection to the electrical system of a motor vehicle, an output for connection to the electrical consumer to be protected, and a ground terminal which is connected via a line to a branch point between the input and the output, wherein at least one component that blocks below a threshold voltage and conducts above the threshold voltage, and a switch connected in series with the component are located in the line, wherein the switch is controlled by a control circuit that closes the switch when a voltage spike occurs and subsequently reopens it.