The utility model belongs to the technical field of grid-connected equipment, and particularly relates to a ventilation and heat dissipation mechanism for an automatic quasi-synchronization device, which comprises a box body, a double-shaft motor, a fan wheel, a dustproof cover, a clamping piece, a lifting mechanism, a supporting table, a rotating block, a cross rod, a
brush head and a temperature sensor, the inner circumference of the dustproof cover is brushed and swept through the
brush head, so that the air inlet is dredged, active dust prevention is achieved, smoothness of a heat dissipation channel is guaranteed, regular manual cleaning is not needed, and the operation and maintenance
workload is reduced; through clamping and separation of a clamping piece and a rotating block and sensing of a temperature sensor on the
internal temperature, intermittent work of the
brush head is achieved, the dredging effect is guaranteed,
energy consumption is reduced, and abrasion of the brush head is reduced; and finally, a dustproof cover is arranged on the bottom surface of the box body, and all parts are intensively arranged in the dustproof cover, so that the occupation of the internal space of the box body can be reduced, the
layout space of core parts is large, and the structural compactness and expansibility are improved.