NDIR Gas Sensor Power Control for Energy Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas-sensor arrangements for monitoring air quality in vehicles lack reliability and accuracy, especially in situations requiring hazard prevention, and have high energy consumption due to their reliance on metal oxide sensors and constant infrared radiation emitter power.
Innovation Solution
A non-dispersive infrared spectrometry (NDIR) gas-sensor arrangement with an infrared radiation emitter and receiver, operated with different powers, using a filter to select specific wavelengths for target gases like CO2 or hydrocarbons, and a controller to adjust power based on detected concentrations for optimal energy use and measurement precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If metal oxide sensors are used for gas detection, then the device can detect target gases, but the measurement precision and reliability deteriorate due to cross-sensitivity to other gases and air humidity
Solution Approach 1:
The patent divides the detection process into multiple wavelength channels, each targeting specific gases. By segmenting the spectral range and using multiple narrow-band filters at different wavelengths, the system can selectively detect different gases (CO, CO2, HC, NO2, O3) independently, eliminating cross-sensitivity interference that plagues metal oxide sensors.
Solution Approach 2:
The patent introduces wavelength-selective filters as intermediaries between the broadband infrared light source and the detector. These filters act as mediators that selectively transmit only the wavelengths absorbed by specific target gases, enabling precise identification and measurement without interference from other gases or humidity.
2Measurement precision
If the infrared radiation emitter operates at high power continuously, then the measurement precision is improved, but the energy consumption increases
Solution Approach 1:
The patent implements periodic scanning through multiple wavelength channels instead of continuous operation at a single wavelength. The system sequentially activates different wavelength bands in periodic cycles, allowing the infrared emitter to operate at high power only intermittently during each scan cycle, thereby reducing overall energy consumption while maintaining detection precision through time-multiplexed measurements.
3Measurement precision
If multiple wavelength channels are scanned sequentially, then the measurement precision for different gases is improved, but the response time increases
Solution Approach 1:
The patent performs preliminary scanning of multiple wavelength channels to establish baseline absorption characteristics before a hazardous condition is detected. This preliminary action allows the system to pre-process and store spectral data, so that when a hazard is detected, the analysis can be performed more quickly using pre-established reference information, reducing the effective response time for critical detections.
4Measurement precision
If narrow-band filters are used for each gas component, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The patent designs the infrared emitter and detector system to be universal across multiple gas types. A single broadband infrared source and a single detector are used for detecting all target gases (CO, CO2, HC, NO2, O3), with the only varying elements being the wavelength-selective filters. This multi-functional approach allows one device configuration to detect multiple different gases by simply changing the filter wavelength, reducing overall system complexity compared to having separate dedicated sensors for each gas.
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 NDIR gas-sensor arrangement provides reliable and accurate measurements with reduced energy consumption by switching between low and high power modes, ensuring high resolution and accuracy when needed, thereby preventing false alarms and efficiently monitoring air quality.
Implementation Method 1
an infrared radiation emitter (3), by means of which infrared radiant energy can be irradiated through a space (2) containing a target gas
Implementation Method 2
When the target gas to be detected with regard to its concentration enters into the beam path between the infrared radiation emitter and the infrared radiation receiver, part of the radiant energy on the specific wavelength is absorbed by the target gas present in the radiation path
Implementation Method 3
a filter (5), by means of which only radiation of a wavelength range that corresponds to the target gas can pass to the infrared radiation receiver (4)
Data Source
AI summary
An NDIR gas-sensor arrangement for measuring a target-gas concentration comprises a variable-power infrared-radiation emitter that can project radiant energy from one side of a space containing the target gas and through the space to the other side thereof, a infrared-radiation receiver on the other side of the space and positioned to be irradiated by the radiant energy projected by the emitter through the space for emitting a signal corresponding to radiation received, and a filter between the receiver and the space and permeable only to radiation of a wavelength range that corresponds to the target gas. A controller connected to the radiation receiver calculates the target-gas concentration on the basis of the signal from the receiver to the controller.