广东电网感性无功补偿配备不足,春节电压偏高的问题日益突出,为此,从电网结构及春节负荷特性两方面分析了电压偏高的原因,结合2007年春节电压的调控情况,对目前电网在春节调压上存在的问题,提出了相应的解决措施和建议,指出电网电压无...广东电网感性无功补偿配备不足,春节电压偏高的问题日益突出,为此,从电网结构及春节负荷特性两方面分析了电压偏高的原因,结合2007年春节电压的调控情况,对目前电网在春节调压上存在的问题,提出了相应的解决措施和建议,指出电网电压无功的控制应首先满足电网安全要求,并在增加电网电压调控手段的同时,加快广东电网自动电压无功控制(Automatic voltage control,AVC)系统的建设,逐步实现无功电压优化调度,确保春节调压的安全,达到提高电压质量、经济运行的目的。电压调控应对措施在2008年春节调压中的成功应用表明了措施的正确性及有效性,为今后电网春节期间的电压调控提供了重要的参考价值。展开更多
Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires...Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires new concepts for power electronics,control systems,and integration strategies.Further degrees of freedom yield to challenges and even more important to possibilities for all kinds of applications.The innovation of the design will be explained and adjustments for power electronics and control will be worked out.The focus of this paper is the 3rd generation of Intelligent Stator Cage Drive(ISCAD)prototypes.This first integrated and compact prototype has been used to re-equip a Geely Emgrand EV.The entire system and the mentioned process are described in detail.In addition,the in-house designed 48 V battery is highlighted.Simulations and measurements give an overall demonstration of the potential and the current status of the drive.展开更多
某海上油田透平机组使用的燃油控制阀是VL 24V系列燃油计量阀(VL 24 Volt Series Liquid Fuel Metering Valve)。该系列阀门使用过程中曾出现阀体内部阻塞、阀芯磨损、控制失效等故障,导致油启失败。由于介质压力高、阀芯行程短、计量...某海上油田透平机组使用的燃油控制阀是VL 24V系列燃油计量阀(VL 24 Volt Series Liquid Fuel Metering Valve)。该系列阀门使用过程中曾出现阀体内部阻塞、阀芯磨损、控制失效等故障,导致油启失败。由于介质压力高、阀芯行程短、计量精度高和技术限制等因素,故障阀门一直无法实现现场维修,返厂维修的阀门须经过出厂测试,以致造成维修成本高、维修周期长、库存积压等问题。某海上油田动力部门通过不断摸索实验,成功总结出一套适用于现场的解决方案。展开更多
从现有波动量法出发,研究用户波动与背景谐波变化对公共联结点谐波电流、谐波电压的影响,提出一种基于用户主导波动量筛选原理的用户谐波发射水平估计方法。提出公共连接点(point of common coupling,PCC)谐波波动伏安特性比的概念,研...从现有波动量法出发,研究用户波动与背景谐波变化对公共联结点谐波电流、谐波电压的影响,提出一种基于用户主导波动量筛选原理的用户谐波发射水平估计方法。提出公共连接点(point of common coupling,PCC)谐波波动伏安特性比的概念,研究系统侧、用户侧谐波波动对其变化的影响;利用统计学筛选方法从PCC点谐波电流测量值中筛选出用户主导谐波电流波动量,以此估计系统谐波阻抗;采用用户谐波电压发射水平修正公式消除背景谐波的影响。对理论模型和实际工程算例的仿真证明该文方法的正确性和有效性。展开更多
文摘广东电网感性无功补偿配备不足,春节电压偏高的问题日益突出,为此,从电网结构及春节负荷特性两方面分析了电压偏高的原因,结合2007年春节电压的调控情况,对目前电网在春节调压上存在的问题,提出了相应的解决措施和建议,指出电网电压无功的控制应首先满足电网安全要求,并在增加电网电压调控手段的同时,加快广东电网自动电压无功控制(Automatic voltage control,AVC)系统的建设,逐步实现无功电压优化调度,确保春节调压的安全,达到提高电压质量、经济运行的目的。电压调控应对措施在2008年春节调压中的成功应用表明了措施的正确性及有效性,为今后电网春节期间的电压调控提供了重要的参考价值。
文摘Through its new technology the ISCAD system provides up to 300 kW with a safe-to-touch 48 Volt battery.This results in a high-performance drive that is intrinsically electrically safe.The novel machine design requires new concepts for power electronics,control systems,and integration strategies.Further degrees of freedom yield to challenges and even more important to possibilities for all kinds of applications.The innovation of the design will be explained and adjustments for power electronics and control will be worked out.The focus of this paper is the 3rd generation of Intelligent Stator Cage Drive(ISCAD)prototypes.This first integrated and compact prototype has been used to re-equip a Geely Emgrand EV.The entire system and the mentioned process are described in detail.In addition,the in-house designed 48 V battery is highlighted.Simulations and measurements give an overall demonstration of the potential and the current status of the drive.
文摘某海上油田透平机组使用的燃油控制阀是VL 24V系列燃油计量阀(VL 24 Volt Series Liquid Fuel Metering Valve)。该系列阀门使用过程中曾出现阀体内部阻塞、阀芯磨损、控制失效等故障,导致油启失败。由于介质压力高、阀芯行程短、计量精度高和技术限制等因素,故障阀门一直无法实现现场维修,返厂维修的阀门须经过出厂测试,以致造成维修成本高、维修周期长、库存积压等问题。某海上油田动力部门通过不断摸索实验,成功总结出一套适用于现场的解决方案。
文摘从现有波动量法出发,研究用户波动与背景谐波变化对公共联结点谐波电流、谐波电压的影响,提出一种基于用户主导波动量筛选原理的用户谐波发射水平估计方法。提出公共连接点(point of common coupling,PCC)谐波波动伏安特性比的概念,研究系统侧、用户侧谐波波动对其变化的影响;利用统计学筛选方法从PCC点谐波电流测量值中筛选出用户主导谐波电流波动量,以此估计系统谐波阻抗;采用用户谐波电压发射水平修正公式消除背景谐波的影响。对理论模型和实际工程算例的仿真证明该文方法的正确性和有效性。