供热机组热电负荷最佳分配方法分析

Research on the Scheme of Optimal Load Distribution for Cogeneration Units

以变工况热力计算为基础,分段采用改进的弗留盖尔公式,分析供热机组的热力特性。通过具体机组进行验证,表明这种热力计算方法具有足够的精度。以实际机组为例,改进热电分离、以热定电的热电负荷分配方案。方案中考虑了热化作功系数的变化,直接以总热耗最小作为电负荷分配指标。同时,依据机组的热力特性,生成热电关系曲线,从而可以将热电负荷调度范围作为限制条件,使分配结果更加合理。通过对比可以发现,这种分配方法可以有效降低机组的总热耗,因而使分配结果明显优于其他方案。该方法可以为电厂与调度部门的负荷调度提供合理的解决方案。

A variable condition calculation method based on improved Flügel equation for cogeneration units was introduced to study the thermal characteristics of those units.This method was applied on the specific units and the calculation result was compared with the experimental data to verify the calculation accuracy.Also,a scheme of optimal load distribution for the cogeneration units was given by dividing the load distribution into two parts： thermal load and electrical load,and dispatching the electrical load according to the thermal load.Simultaneously,this scheme considered the variation of the thermal power coefficient,and the heat consumption minimization was considered as an optimization variable of electrical load distribution.In addition,the diagram of thermoelectric relationship was established on the basis of the thermal characteristics of specific units so that the limitation of load dispatching could be taken into consideration.The comparison between the proposed scheme and other ones indicates that this scheme can decrease the total heat consumption effectively and thus has a better performance.Therefore,this new method can offer the power plants and power dispatch departments a more advisable solution of the load dispatching.