On-line vertical track long wave irregularity monitoring method and system

The invention discloses an on-line vertical track long wave irregularity monitoring method and a system. According to the system, a pitch gyroscope is arranged on a framework above a one-class spring of a train walking part, a speed measuring sensor is arranged inside an automobile end cover of a train, and output ends of the pitch gyroscope and the speed measuring sensor are both accessed to a central processing unit. The monitoring method comprises the following steps: acquiring a framework inclination angle speed signal of the train through the pitch gyroscope, acquiring an operation speed signal of the train through the speed measuring sensor, performing time-space domain conversion on the two acquired signals through the central processing unit so as to obtain a time-space domain sequence, performing quadratic integration on the time-space domain sequence by using a filter method, eliminating a trend term generated in integration by using a trend term elimination method so as to obtain a track vertical displacement estimation value, and establishing a compensation filter for eliminating the amplitude and phase deviation of the tract vertical displacement estimation value. The monitoring method has the advantages of low cost and good engineering implementation property, and on-line real-time monitoring is achieved.