Experimental Research on Passenger Vehicle’s Air Conditioner Usage Characteristics and Its Influences on Fuel Consumption

The driving cycles for testing (i.e. DC) are the basis of automotive performance testing. Generally, because of the lack of key data, such as the air-conditioning usage, the whole vehicle driving loading, the selection of shift gears, and so on, the significant difference between the results of DC and actual road testing cannot be reduced when the DC was developed. So the key factors were studied in this paper, including the air-conditioner usage characteristics and its effects on the whole automotive’s fuel consumption. Three typical cities, Changchun, Hefei and Nanchang, were determined to conduct the tests of the questionnaire, the mobile APP, the special roadway tests, etc. In addition, the bench tests were carried on at the same time. All the test data were collected and analyzed for the development of China Driving Cycles. The analysis of the questionnaire and the mobile APP shows that the frequency of air conditioning in cooling mode was 85% when the temperature was higher than 30 ℃ and the frequency in heating mode was 90% when the temperature was lower than 0 ℃. In the special roadway tests, compared with the 0th gear of the air conditioner blowing machine, the 100 kilometers average fuel consumption of 1st and high gear increased by 8.5% and 16.7% respectively. According to the laboratory NEDC Bench tests at 30 ℃, when the air conditioner was opened in cooling model, the 100 kilometers average fuel consumption increased by about 25%, compared with the tests in which the air conditioner was closed.