Boiler coal pulverizing system and control method thereof

The invention discloses a boiler coal pulverizing system and a control method thereof.The boiler coal pulverizing system comprises a hearth, a powder pipe quick-closing valve, a separator, a coal feeder, a coal feeder lower gate plate, a coal mill body, a capacity air door, a smoke air door, a cold primary air door, a hot primary air door, an induced draft fan and a powder pipe, and the coal feeder is connected with the coal mill body through the lower gate plate door; the coal mill body is connected with a separator, the separator is connected with a hearth through a powder pipe, and a powder pipe quick-closing valve is mounted on the powder pipe; the smoke air door, the cold primary air door and the hot primary air door are connected with the capacity air door and the bypass air door after being connected in parallel and converged, the capacity air door is connected to the separator, the bypass air door is connected to a feed port, connected with the coal mill body, of the coal feeder, and the smoke air doo