When car consumers buy vehicles, in addition to considering the performance of the car, such as power, handling, and safety, the highly-rated NVH performance, which can provide driving and passenger comfort, has become a factor for consumers to buy a car. In the process of vehicle development, all developing car manufacturers need to evaluate the performance of competing models to develop new models with higher performance.
What is NVH technology?
NVH is a general term for three items: Noise, Vibration, and Harshness. Low NVH technology of vehicle power motor, measured acceleration noise test of power vehicle <67dB (without soundproof cover), in line with CNS 5799 noise test regulations. The maximum noise of electric vehicle driver's right ear is 68dB at 0~80 kph.
What is NVH testing?
NVH is to detect the indicators of Noise, Vibration, and Harshness. The level of vibration and noise has always been one of the evaluation indicators for consumers to purchase products, and the quality of its performance level is also an important factor affecting the added value of products.
NVH technology features:
- Noise: Unpleasant, loud sounds.
- Vibration: Because the material cannot be completely uniform, the accuracy of the manufacturing is limited, the wear after use, etc., cause the vibration of the moving objects and machinery.
- Roughness: The discomfort caused by the vibration and noise generated by the road surface, the engine, and the vehicle body during the running of the vehicle.
Technical overview: The low NVH drive motor for electric vehicles maintains its high-efficiency characteristics, but reduces NVH through slot-to-pole ratio design and slot arc trimming. The measured acceleration noise of electric vehicles is <67dB (without soundproof cover), in line with CNS 5799 Noise test regulations; maximum right ear noise of electric vehicle driver at 0~80 kph 68dB(A) Technical features: High efficiency and low NVH drive motor, with 210 Nm torque output, the maximum speed of 8000 rpm, maximum efficiency of 96 %. It has the characteristics of wide-area and high-efficiency and can have high-efficiency performance for wide-area torque and speed operation. In addition, the NVH characteristics have also been verified to comply with CNS regulations. Suitable for commercial vehicles and general cars.
Why is NVH testing important?
Through the NVH test, can reflect the inadequacy of the vehicle, and then improve and enhance its performance, as well as enhance the comfort of the occupants. In the process of moving the vehicle, the driver and passengers can feel whether it is comfortable or not. Vehicles with good performance have low vibration and noise, are quiet and comfortable to drive and are less prone to fatigue even on long distances. This is achieved through rigorous design, manufacturing, and testing.
NVH application range:
All kinds of general sedans, passenger cars, commercial vehicles, and urban vehicles with power requirements between 50 and 70 kW. Applicable to: Gearbox, Electric Vehicle, Magnetic Brake, etc. It can be used for vibration and noise design, optimization, and verification of engine vehicles/hybrid electric vehicles/electric vehicles and their power systems, as well as indicators for the development of vehicle sound quality engineering.
NVH test items:
- Idle Test: When the vehicle is started, the idling NVH is the earliest NVH performance item felt by the occupants in the car, so the idle speed test method is used to judge the idling conditions of the vehicle (P, N, D gear), the occupants in the car are very concerned about the vehicle. NVH perception.
- Acceleration Test: After the vehicle is started, the driver will accelerate the vehicle to within the legal speed limit. Therefore, the acceleration NVH is an NVH performance item that can be felt by the occupants of the vehicle after idling. Influence of occupants.
- Constant Speed Test: When the vehicle is driving on the road outside the alliance, it usually drives at a constant speed, so the constant speed NVH is also the most easily experienced NVH performance item for the occupants in the vehicle. Therefore, the constant speed test is used to evaluate the effect of constant speed NVH on the occupants of the vehicle under constant speed conditions.
- Coast Test: When the vehicle enters the urban area from the outer road, the driver usually needs to slow down and coast to a low speed, so this coasting test is used to evaluate the impact of the vehicle's coasting vibration and noise on the occupants of the vehicle under this condition.
- Wind Noise Test: When the vehicle is driving on the highway at high speed (>100kmh), the wind shear sound will become the main noise source of the vehicle, so the wind noise test is used to evaluate the impact of wind noise on the occupants of the vehicle.