共查询到19条相似文献,搜索用时 406 毫秒
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阐述引起三相电压不平衡的主要因素及危害,介绍三相不平衡度的计算方法。对国家标准GB/T15543-2008《电能质量三相电压不平衡》的内容、适用范围、电压不平衡度的允许值、不平衡度的测量和取值及改善三相不平衡的措施等进行解读。 相似文献
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《Planning》2014,(24)
本文针对三相逆变器负载不对称引起逆变器输出电压不对称的情况,采用基于同步旋转坐标系的双PI控制策略,对三相逆变器输出电压进行控制,用Matlab对系统进行建模仿真,仿真结果表明逆变器输出电压的平衡度达7%以下。 相似文献
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《Planning》2014,(3)
谐波技术监督应包括电压波动和闪变、三相电压不平衡度和电压正弦波形畸变率等电能质量指标。目的是使电网的电能质量指标符合有关标准,保证电网安全、稳定、优质、经济、可靠运行,向用户提供合格的电能。 相似文献
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低压配电系统三相负荷在实际运行中常出现不平衡甚至严重不平衡,经测试度非常严重。三相负荷不平衡对低压电网、配电变压器均造成危害。为了今后在设计、施工中能重视三相负荷的平衡.本文将对造成不平衡的原因及其危害作一下分析。 相似文献
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配变三相负荷平衡是农村电网管理中的重要问题,要提高农电管理水平,特别是对农网进行的规划和改造,需对其足够重视.电压与线损有密切的关系,减少线路电压损耗可明显提高经济效益,因此,三相负荷平衡在线损中的重要性就可想而知了,以下只要从三相负荷的不平衡影响,以及如何实现三相负荷平衡来分析,进而得出三相负荷在线损管理中的重要性. 相似文献
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通过分析三相四线制供配电系统中性线开断且三相负载不平衡时,产生过、欠电压的危害性,探讨住户装设过、欠电压保护电器的必要性。对三相供电住户采用单相或三相自恢复式过、欠电压保护电器的利弊进行分析、比较,指出住户三相供电存在的安全隐患,建议对自恢复式过、欠电压保护电器多加讨论。 相似文献
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本文通过对220kV某变电站10kV电容器由于三相电压不平衡导致跳闸原因分析,找出引起电压不平衡的因素,为以后查找电容器组故障原因积累经验。 相似文献
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《Planning》2014,(19)
本文通过现场测试中发现电容式电压互感器的电容量异常增加,且三相线电压明显不平衡,经进一步试验分析,判定电容器内部串联电容已部分击穿,并提出了电容式电压互感器运行及测试相应注意事项。 相似文献
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结合多年住宅配电设计及实践调研,从负荷计算、过(欠)电压保护、剩余电流动作保护方面,对住宅分户箱三相配电进行分析;对现行规范规程不合理、不完善之处提出建议;在三相平衡、中性线断线保护及间接接触防护方面,提供有效解决方案。 相似文献
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设计一款三相逆变交流电源,输出正弦信号频率为50Hz,负载Y型连接时线电压有效值可达24V,负载线电流有效值最大为2A。系统由三相逆变驱动主电路、滤波电路、STM32最小系统、信号隔离电路、SPWM(正弦脉宽调制)信号发生器、电压和电流测量电路和LCD显示等功能电路组成。测试结果表明,室温下输入直流电压为36V,负载线电流有效值Io在0~2A间变化时,各相负载调整率不大于0.3%,电能转换效率可达88%。 相似文献
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简要介绍了电气隔离和四极开关的用途和功能,分析了三相断电后中性线带危险电压的原因,阐述了单电源不同类型接地系统对开关极数的不同要求和滥用四极开关的后果等内容,以期指导电气维修和安装时正确选用四极开关。 相似文献
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ABSTRACTThis paper presents the simple voltage regulation scheme using a three-phase static VAr compensator (STATCON) for a stand-alone self-excited induction generator (SEIG) that uses variable-speed wind generation system. Most of the loads are inductive and need an equal amount of leading VArs, which is generated by the STATCON and injected at point of common coupling instantaneously. The one cycle control technique is considered and modified to implement for VAr compensation of SEIG voltage regulation. To emphasis the controller characteristics, a STATCON is designed for a 3-Ø, 0.75?kW, 415?V, 1.8?A Induction Machine and tested in simulation using MATLAB/SIMULINK software. 相似文献
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Treatment of dye wastewater containing acid orange II using a cell with three-phase three-dimensional electrode. 总被引:9,自引:0,他引:9
The removal of color and chemical oxygen demand (COD) from simulated dye wastewater containing Acid Orange II was experimentally investigated using coagulation-electrooxidation. Two kinds of coagulation methods, ferrous-mediated coagulation and electrocoagulation were tested as pretreatment. The electrooxidation was carried out in a cell with a three-phase three-dimensional electrode using granular activated carbon as particle electrodes. Particular attention was paid to probe the effect of cell voltage, airflow rate, solution conductivity and treatment time on the electrochemical treatment efficiency. The experimental results showed that the coagulation-electrooxidation process could efficiently remove the color and the COD from the simulated dye wastewater. The overall COD and color removal efficiencies reached as high as 99% and 87%, respectively, by ferrous coagulation (molar rate of Fe(II)/ dye: 0.5) and 30-min electrolysis (cell voltage: 20.0 V and airflow: 0.1 m3 h(-1)). 相似文献
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A. Ramesh Babu T. A. Raghavendiran V. Sivachidambaranathan J. Barnabas Paul Glady 《国际自然能源杂志》2018,39(2):117-121
The main objective of this paper is to develop a novel inverter to produce multilevel output voltage. This paper proposes the cascaded H-bridge with sub-multilevel inverter (CHBSMLI) using three unequal DC sources in order to get 15-level output voltage. The unequal DC sources can be obtained from photovoltaic cell. The proposed CHBSMLI reduces the number of switches which in turn reduces the switching losses. The multicarrier sine Pulse Width Modulation (PWM) technique is proposed to obtain pure sinusoidal signal with reduced total harmonic distortion (THD). The performance analysis of the proposed three-phase CHBSMLI carried out using MATLAB/simulink with minimised THD and switching loss. The gating signals are generated using a Spartan-3E FPGA processor. The single-phase 15-level CHBSMLI with PWM developed to validate the simulation result. 相似文献
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本文介绍了地埋管地源热泵系统的基本原理与特点,总结了地埋管系统出现热失衡的几种常见情况,分析了出现热失衡的原因。并针对常见的热失衡现象,提出了具体的解决措施。 相似文献