Residual pressure detection method and system

The invention discloses a residual pressure detection method. The method comprises the following steps: reading a pressure value of a first air pressure sensor; reading a temperature value of the first air pressure sensor; reading a pressure value of a second air pressure sensor; calculating a pressure difference value, and caching the difference value within 1 minute; if the measurement time is longer than 1 minute, judging whether the difference value within 1 minute is stable or not; if so, entering the next step, and if not, returning to the first step; calculating an inherent deviation; reading a pressure value of the first air pressure sensor; reading a pressure value of the second air pressure sensor; calculating a pressure difference value; performing offset processing; and calculating the residual pressure value according to the pressure difference value. Therefore, the two air pressure sensors are used for measuring the air pressure of the high-pressure side and the air pressure of the low-pressure