Abstract: The strong stable combustion technology of pulverized coal pre - gasification can balance stable combustion and NO emission control. Based on this principle, a rapid peaking burner for flexible peaking of power plant boilers had been developed, and the operation performance under different loads, the minimum stable combustion load and rapid load variation capacity of the burner were studiedon a 5 MW combustion test rig. The results showed that, after entering the small pre-gasification chamber attached to the burner, the pulverized coal would undergo gasification reaction and transform into preheated fuel composed of high temperature gas and hot carbon particles. Under low load, the preheated fuel would burn rapidly after entering the furnace, forming a high temperature zone at the root to ensure the steady combustion of the furnace. With the increase of load, the gasification reaction in the pre - gasification chamber wasmore complete, and reducing atmosphere was formed with the return flue gas to achieve effective nitrogen reduction. The NO emission atfull load was 159 mg/ m(6% O) without any auxiliary means, and the carbon content of fly ash was 3.4%, meaning combustion efficiency was 99.71%. The rapid peaking burner could still maintain the stable combustion of the furnace under the ultra-low load of 9%, andthe outlet oxygen remains stable during the long-term continuous operation of more than one hour. In the range of 15% to 100% load, therapid load reduction and load rise processes were completed in 8 min and 9 min, and the load ramp rates reached 10.63% / min and9.44% / min respectively. During the process of load change, the combustion in the furnace remained stable, and the temperature distribution had a fast response to the load change, which verified the excellent performance of the burner in the process of rapid peak regulating.