Air conditioner
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing air conditioning apparatuses for vehicles face challenges in accurately estimating motor coil and compressor discharge temperatures, especially in abnormal high-temperature environments, leading to inadequate overheating protection without additional temperature detection means.
Innovation Solution
The air conditioning apparatus estimates motor coil and compressor discharge temperatures based on the detected temperature near semiconductor switching devices in the inverter, using pressure loading characteristics, allowing for effective overheating protection without additional sensors by reducing or stopping the compressor when thresholds are exceeded.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If temperature sensors are installed at the compressor discharge and motor coil locations to detect temperatures, then temperature detection accuracy is improved, but device complexity and cost increase
Solution Approach 1:
The patent creates a virtual copy of the temperature detection function by using the inverter's existing temperature sensor to estimate compressor discharge temperature and motor coil temperature through calculation models, rather than installing physical temperature sensors at these locations. This copying approach achieves the measurement function without adding physical components.
Solution Approach 2:
The patent introduces an estimation calculation model as an intermediary between the inverter's temperature sensor and the compressor/motor temperature parameters. This intermediary translates the inverter temperature sensor data into estimates of compressor discharge temperature and motor coil temperature, enabling indirect measurement without direct sensor installation.
2Device complexity
If estimation calculations use parameters not directly influenced by temperature (such as discharge pressure and rotational speed), then device complexity is reduced, but measurement precision deteriorates in abnormal high-temperature environments
Solution Approach 1:
The patent incorporates feedback by using the inverter temperature sensor (which directly detects temperature) as part of the estimation calculation for compressor discharge temperature and motor coil temperature. This feedback mechanism ensures that the estimation model responds to actual temperature conditions, improving accuracy in abnormal high-temperature environments while maintaining a simple configuration.
Solution Approach 2:
The patent changes the parameter set used in estimation calculations to include the inverter temperature sensor output, which is directly temperature-influenced. This parameter change allows the estimation model to adapt to abnormal temperature conditions while keeping the device configuration simple, resolving the trade-off between simplicity and accuracy.
3Reliability
If additional temperature detection means are installed to improve overheating protection, then reliability is improved, but volume and cost increase
Solution Approach 1:
The patent makes the inverter temperature sensor serve multiple functions: it detects inverter temperature for inverter protection and simultaneously provides data for estimating compressor discharge temperature and motor coil temperature for compressor and motor overheating protection. This multi-functionality improves reliability without requiring additional sensors or increasing apparatus volume.
Solution Approach 2:
The patent enables the inverter's existing temperature detection system to serve the additional function of monitoring compressor and motor temperatures through estimation calculations. This self-service approach allows the system to perform multiple protection functions using its own existing resources, improving reliability without external additions.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is an air conditioning apparatus that is capable of suppressing increases in volume and cost of the apparatus and performing more suitable overheating protection. An electric compressor is an inverter-integrated electric compressor (10) integrally including a compressor (5), an electric motor (6) that drives the compressor (5), and an inverter (7) including a temperature sensor (11) that detects the temperature in the vicinity of a semiconductor switching device, wherein a controller (3) estimates a discharge temperature of the compressor (5) on the basis of a correlation of respective pressure loading characteristics for the detected temperature of the inverter (7), for the rotational speed of the compressor (5), and for the motive force of the compressor (5) in a refrigerating cycle (2).