As they deliver dispatchable renewable energy, biomass power plants are expected to play a key role in the stability of the future electricity grids dominated by intermittent renewables. Large-scale, biomass-fired power plants are often retrofitted from coal-fired plants. Such a fuel modification combined with decreasing pollutant emission limits and higher requirements in terms of load flexibility can lead to a decrease of the maximum power delivered by the unit. The limiting factors are partly related to the control systems of those plants. In this paper, we present the results of the upgrading of an 80 MW_e, retrofitted biomass power plant that was achieved by improving the dynamic control of the combustion process. Thanks to the addition of virtual air flow sensors in the control system and the re-design of the combustion control loops, the undesired effects of a recent $10\text{\%}$ power increase on NO_x emissions were more than compensated. The accurate control of the local NO_x production in the furnace resulted in a decrease of these emissions by $15\text{\%}$ with an increased stability. This study will help increasing the cost-effectiveness of such conversions, and facilitate the development of dispatchable, renewable power units able to contribute to the grid stability.

由于生物质发电厂提供可调度的可再生能源，因此它们在以间歇性可再生能源为主导的未来电网的稳定性中将发挥关键作用。大型的生物质燃料发电厂通常是从燃煤电厂进行改造的。这种燃料改良加上降低的污染物排放限制和对负载灵活性的更高要求，可能导致该装置所传递的最大功率降低。限制因素部分与那些工厂的控制系统有关。在本文中，我们介绍了80 MW _e的升级结果，对生物质发电厂进行了改造，这是通过改善燃烧过程的动态控制来实现的。由于在控制系统中增加了虚拟空气流量传感器，并重新设计了燃烧控制回路，因此，最近的不良影响$10\text{％}$NO _x排放的功率增加得到了补偿。本地NO的精确控制_X在炉生产导致通过降低这些排放$15\text{％}$具有更高的稳定性。这项研究将有助于提高此类转换的成本效益，并有助于开发可调度的可再生电力装置，从而有助于电网的稳定性。