Zero calibration method for particulate matter sensor

The invention provides a zero calibration method for a particulate matter sensor, and belongs to the technical field of gas detection, zero calibration operation is performed based on a zero calibration system for the particulate matter sensor, and the zero calibration system for the particulate matter sensor comprises a first three-way valve, the particulate matter sensor, a particulate matter filter, a sampling pump and a second three-way valve which are communicated in sequence; the zero calibration method for the particulate matter sensor comprises the following steps: operating a sampling pump, and extracting an air sample with a preset flow; closing a normally-opened opening of the first three-way valve, opening a normally-closed opening of the first three-way valve, closing a normally-opened opening of the second three-way valve, and opening a normally-closed opening of the second three-way valve, so that the first three-way valve, the particulate matter sensor, the particulate matter filter, the sampl