Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter ...Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter in 2018 to spring in 2019,the largest SD occurred in this area over the past 10 years,especially in core zones of the Lancang River Source Region.Field research results show that the main causes of the major SD include weak infrastructure(i.e.,roads,communications,warm sheds,and insufficient forage reserve),low rate of domestic animals for sale before the SD,and low loss settlement rate.SD occurrence could furtherly reduce the ability of disaster prevention,mitigation and relief of disaster loss.In the future,heavily affected SD areas should improve the forecasting ability of snowfall incidents,strengthen infrastructure construction,implement grass and livestock balance strategies,optimize livestock structure,improve loss settlement rate,and develop a modern compound model of animal husbandry development model that combines breeding,slaughtering and deep processing of animal product.展开更多
藏中联网工程输电距离长,末端西藏电网容量小、负荷轻、稳定裕度低且频率稳定与有功功率、无功功率高度耦合;高压直流输电系统、光伏发电系统等电力电子设备众多,大型主变空载合闸将引发系列安全问题,此外静止无功补偿器(static var com...藏中联网工程输电距离长,末端西藏电网容量小、负荷轻、稳定裕度低且频率稳定与有功功率、无功功率高度耦合;高压直流输电系统、光伏发电系统等电力电子设备众多,大型主变空载合闸将引发系列安全问题,此外静止无功补偿器(static var compensator,SVC)控制参数整定不当易产生电磁振荡。该文提出了通过优化充电启动顺序的无功电压控制方法;加装合闸电阻、选相合闸装置并配合运行方式调整的励磁涌流和过电压综合防控策略;兼顾电磁振荡抑制和无功调节性能的SVC控制参数优化方法。制定了考虑光伏发电、直流输电系统运行风险及电网频率稳定风险的调控运行策略。仿真分析和系统调试结果验证了所提措施的有效性。展开更多
基金supported by Open-ended Fund of Qinghai Province Key Laboratory of Physical Geography and Environmental Process(2018-QZH-K01)National Natural Science Foundation of China(41701505,41871064)the foundation of PHD development in Yichun University(201-3360118009)
文摘Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter in 2018 to spring in 2019,the largest SD occurred in this area over the past 10 years,especially in core zones of the Lancang River Source Region.Field research results show that the main causes of the major SD include weak infrastructure(i.e.,roads,communications,warm sheds,and insufficient forage reserve),low rate of domestic animals for sale before the SD,and low loss settlement rate.SD occurrence could furtherly reduce the ability of disaster prevention,mitigation and relief of disaster loss.In the future,heavily affected SD areas should improve the forecasting ability of snowfall incidents,strengthen infrastructure construction,implement grass and livestock balance strategies,optimize livestock structure,improve loss settlement rate,and develop a modern compound model of animal husbandry development model that combines breeding,slaughtering and deep processing of animal product.
文摘藏中联网工程输电距离长,末端西藏电网容量小、负荷轻、稳定裕度低且频率稳定与有功功率、无功功率高度耦合;高压直流输电系统、光伏发电系统等电力电子设备众多,大型主变空载合闸将引发系列安全问题,此外静止无功补偿器(static var compensator,SVC)控制参数整定不当易产生电磁振荡。该文提出了通过优化充电启动顺序的无功电压控制方法;加装合闸电阻、选相合闸装置并配合运行方式调整的励磁涌流和过电压综合防控策略;兼顾电磁振荡抑制和无功调节性能的SVC控制参数优化方法。制定了考虑光伏发电、直流输电系统运行风险及电网频率稳定风险的调控运行策略。仿真分析和系统调试结果验证了所提措施的有效性。
