In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel ...In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.展开更多
当电网出现有功缺额并导致频率跌落时,风电机组可以通过释放自身轴系动能为电网提供短时频率支撑(short-term frequency support,STFS)。如何利用有限的风电机组轴系动能最大限度地支撑电网频率,是当前研究的热点问题。针对风电机组可...当电网出现有功缺额并导致频率跌落时,风电机组可以通过释放自身轴系动能为电网提供短时频率支撑(short-term frequency support,STFS)。如何利用有限的风电机组轴系动能最大限度地支撑电网频率,是当前研究的热点问题。针对风电机组可释放动能和电网频率变化率约束下的电网最大频率偏差最小化问题,该文提出一种基于有功功率互补控制(active-power complementation control,ACC)的风电机组STFS策略,揭示STFS过程中风电机组的最小动能释放机理,并证明采用ACC释放全部轴系动能的STFS策略为上述问题的最优解。最后,基于含风电的电网动模实验平台的实验结果验证该文提出STFS策略的可行性与频率支撑效果。展开更多
风火打捆直流外送系统中风电场和电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)控制系统可能会激发火电机组的轴系扭振。文章首先采用复转矩系数法和特征值分析法识别出LCC-HVDC...风火打捆直流外送系统中风电场和电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)控制系统可能会激发火电机组的轴系扭振。文章首先采用复转矩系数法和特征值分析法识别出LCC-HVDC定电流、风机直流电压外环控制是影响轴系-控制交互模式的关键控制环节。然后,通过推导系统传递函数,提取出反映LCC-HVDC定电流和风机直流电压外环控制对轴系-控制交互模式影响的多条关键控制路径,包括HVDC定电流控制路径、风机直流电压外环控制路径和两者间交互控制路径。进一步,定量计算每条作用路径在轴系-控制交互模式处的阻尼系数,并通过相位补偿在关键控制路径上分别设计附加阻尼控制来提高对应阻尼系数,从而抑制火电机组轴系扭振。最后,基于PSCAD/EMTDC的详细电磁暂态仿真,验证了理论分析的正确性及振荡抑制策略的有效性。展开更多
基金Project of Science & Technology Development Guidance of Jilin Province (No.200405033)
文摘In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.
文摘当电网出现有功缺额并导致频率跌落时,风电机组可以通过释放自身轴系动能为电网提供短时频率支撑(short-term frequency support,STFS)。如何利用有限的风电机组轴系动能最大限度地支撑电网频率,是当前研究的热点问题。针对风电机组可释放动能和电网频率变化率约束下的电网最大频率偏差最小化问题,该文提出一种基于有功功率互补控制(active-power complementation control,ACC)的风电机组STFS策略,揭示STFS过程中风电机组的最小动能释放机理,并证明采用ACC释放全部轴系动能的STFS策略为上述问题的最优解。最后,基于含风电的电网动模实验平台的实验结果验证该文提出STFS策略的可行性与频率支撑效果。
文摘风火打捆直流外送系统中风电场和电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)控制系统可能会激发火电机组的轴系扭振。文章首先采用复转矩系数法和特征值分析法识别出LCC-HVDC定电流、风机直流电压外环控制是影响轴系-控制交互模式的关键控制环节。然后,通过推导系统传递函数,提取出反映LCC-HVDC定电流和风机直流电压外环控制对轴系-控制交互模式影响的多条关键控制路径,包括HVDC定电流控制路径、风机直流电压外环控制路径和两者间交互控制路径。进一步,定量计算每条作用路径在轴系-控制交互模式处的阻尼系数,并通过相位补偿在关键控制路径上分别设计附加阻尼控制来提高对应阻尼系数,从而抑制火电机组轴系扭振。最后,基于PSCAD/EMTDC的详细电磁暂态仿真,验证了理论分析的正确性及振荡抑制策略的有效性。