皖电东送机组响应电网大频差控制策略分析与应用

Analysis and Application of Large Frequency Difference Control Strategy in Response to Power Grid for Anhui Electric Power East Transmission Unit

一次调频通过机组的蓄能来调节电网的负荷,从而优化电网频率的稳定性。一次调频是由电厂设备调速系统自动完成,而一次调频的调节幅度由电厂蓄能所决定。现在大型发电机组主要采用直流锅炉,相对于传统的汽包炉来说,其机组的蓄能较少。为保证一次调频有更大的调节裕度,提高机组蓄能是最有效的途径,但研究表明过度提高机组蓄能对机组经济性会产生不利影响,在面对长时大频差时后续作用能力也有限。针对长时大频差动作,提高机组响应能力,特别是锅炉侧的及时响应是确保在出现持续大频差的情况下有足够的能量去参与频率调整的关键。对电网大频差动作进行逻辑优化,通过机组调频试验,证明其对提高电网频率大幅长时变化时机组的调节能力有帮助。

Primary frequency regulation relies on the energy storage of the generator unit to compensate the power variation caused by the load on the grid and optimizes the stability of the grid frequency.The primary frequency regulation is automatically completed by the power control system of the power plant and the capability of the primary frequency regulation is determined by the energy storage of the power plant.Nowadays large-scale generator units mainly use DC boilers,which have smaller energy storage than the traditional drum boilers.Therefore,in order to ensure a larger regulation margin for primary frequency regulation,improve the unit energy storage is the most effective method.But the research shows that the excessive increasement of unit energy storage would have a negative effect on unit economy and has limited subsequent capacity in the event of long-term,large frequency differences.Aiming at complying the need of primary frequency regulation for the long duration and large frequency difference situations,improving the response capability of the unit,especially the fast response from the boiler side,is the key to ensure enough stored energy to participate in the frequency adjustment under the condition of continuous large frequency difference.This paper carries out optimization on large frequency difference action of power grid and the improvement to the primary frequency regulation capability of the generator unit after applying the proposed optimization is verified through experimental test.