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针对激光诱导击穿光谱技术应用于煤粉颗粒流成分的直接检测，研究不同激光光源参数对煤粉颗粒流等离子体特性的影响，以优化煤粉颗粒流检测时的激光波长、能量等光源参数。选取电厂常用燃煤神木混作为实验对象，经碾磨后得到粒径小于0.2 mm的样品，利用绞笼式给粉机产生稳定煤粉流。研究分析不同激光波长下等离子体温度、电子密度以及特征谱线强度等特性随激光能量的变化趋势。研究结果表明，在不同波长激光作用下，煤粉颗粒流的等离子体温度、电子密度和特征谱线绝对强度随激光能量在一定范围内的变化趋势基本一致，但在激光波长为1064 nm条件下，随着激光能量的增加，这些特性参数增加的速度要比532 nm时更快，这主要是由于短波长(532 nm)的光子效率更高，在较低的能量条件下，就会达到饱和状态。“,”Laser-Induced Breakdown Spectroscopy (LIBS) was used to detect the components of coal particle flow . The influences of different parameters of laser on the plasma characteristics of coal particle flow were studied. The parameters included different laser wavelengths and laser energies. The coal commonly used in the power plants in China was chosen as the experimental sample. Before the experiment, the diameter of coal particle was less than 0.2 mm by sieving method. Then the experiment was carried out at different laser wavelengths and laser energy. The results show that the variations trends of the plasma temperature, electron density and the lines intensity with laser energy are consistent under different laser wavelengths. However, as the laser energy increases, these characteristic parameters increase faster under 1 064 nm than that under 532 nm. The main reason is that the short wavelength (532 nm) with higher photon efficiency would reach the saturated state under lower laser energy.