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三相永磁同步电动机的研制邓隐北,戴羌平(郑州大学450052)史卫平,张瑞安(开封博达电机公司)1永磁电动机转子的结构设计1.1永磁体的性能选择与尺寸确定该电机选用的永磁材料为西安兴华新型材料厂生产的30-SH型钦铁硼(NdFeB),经测试,特性参数... 相似文献
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真空泵用屏蔽式永磁同步电机发热严重,因此在设计阶段准确预测其温度对于真空泵系统的安全稳定运行具有重要意义。针对当前电机电磁场-温度场双向耦合计算方法只能考虑温度对电机材料物理性质参数的影响,提出了一种电机电磁场-温度场互相迭代计算方法。该方法不仅能够考虑温度对电机损耗和永磁体磁性能的影响,还能够考虑温度对电机部件材料导热能力和散热能力的影响,使电机电磁场和温度场预测更加符合实际情况。以一台1.5 kW屏蔽式永磁同步电机作为研究对象,基于提出的方法对电机的电磁性能和温度特性进行分析,并将分析结果与电磁热双向耦合计算结果进行了对比。此外还利用提出的互相迭代法分析了环境温度对电机温升的影响。该研究不仅可以为屏蔽式永磁同步电机优化设计提供理论依据,还可以为其运行安全性和可靠性提供参考。 相似文献
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提高永磁电机性能的新途径——聚磁效应林德芳中国科学院电工研究所(100080)通过磁路分析,提出提高永磁电机性能的新途径—高磁密磁路结构,从而大幅度提高电机的出力和快速响应。1引言90年代以来,永磁电机已广泛用于“3A”场合(OA-办公自动化;FA-... 相似文献
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稀土永磁材料及电机发展概况 总被引:2,自引:1,他引:2
介绍稀土永磁材料的性能、生产概况、存在的问题和对策,以及稀土永磁电机研制概况,并对不同永磁材料电机的性能进行了比较,指出钕铁硼永磁电机的优越性和应用前景。 相似文献
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软磁复合材料适合用于制造结构复杂的小型永磁电机。在三维有限元分析的基础上,进行了以软磁复合材料为定子铁心的三相爪极式永磁电机的优化设计以及参数计算和性能分析;得到的结果对该种材料的应用具有一定参考价值。 相似文献
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特高压直流严重故障时的紧急切负荷措施是阻止受端电网频率跌落的必要手段。结合稳控和营销负控系统特点,本文提出了以企业可中断负荷为精准控制对象的负荷控制系统。比较分析了稳控装置负荷控制与营销系统负荷控制方式的优缺点,介绍了精准负荷控制系统的整体架构,其中重点阐述了系统各层级功能定位、负荷控制原则和防止系统误动与拒动等关键技术。本文提出的精准负荷控制系统已在江苏电网建成投运,实现了350万千瓦秒级精准实时控制和100万千瓦毫秒级紧急控制能力。 相似文献
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高层建筑消防供电,在供电方案中处于最高供电层级,并具有独立性的特点。完善的消防供电系统可以保障建筑物内各种消防用电设备及时可靠地运行,发生事故时可有效疏散人员、物资并控制火势蔓延。根据我国城市高层建筑消防负荷在电网供电系统中所处的负荷等级,结合国家及行业标准,分别对建筑消防供电系统的双电源接线、自备油机双电源接线等4种供电方案进行了详细的比较和分析,得出了高层建筑消防负荷供电的合理主接线方案,并指出了消防负荷供电路径的选择及敷设方法。 相似文献
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Results of computational experiments carried out on an adaptation of the AEP/IEEE 30 bus test system are reported. Some selected buses were modeled using an exponential type of load model. Three cases are considered. In the first case it is assumed that the specified load at modeled buses is obtained with unity voltage. In the second case it is assumed that the transformer taps have been adjusted to give all industrial-type consumers one per unit at the low-voltage panel when the high-side voltage corresponds to the standard optimal power flow (OPF) solution. The third case differs from the second in that the specified power demand is assumed to take place when the high-side voltages correspond to the intact case of the standard security constrained OPF solution. It is concluded that a decrease in fuel cost can be obtained in some instances when load models are incorporated in security constrained OPF studies during contingencies only. In situations where a decrease in fuel cost is obtained in this manner, the magnitude of decrease depends on the total percentage of load fed by fixed tap transformers and the sensitivity of these loads to modeling 相似文献
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王亚忠 《电力系统保护与控制》2008,36(17):60-61
在导出双绕组变压器总损耗的基础上,用数学方法推导出了考虑电压变化影响的变压器经济负荷系数的计算公式,举例说明了不能忽略电压变化影响的原因,并得出当双绕组变压器按损耗最小曲线运行时,其负载损耗为常数的结论。 相似文献
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In general, electric power companies must prepare power supply capability for maximum electric load demand because it is very difficult at present to store electric power. It takes several years and requires a great amount of money to construct power generation and transmission facilities. Therefore, it is necessary to forecast long-term load demand exactly in order to plan or operate power systems efficiently. Several methods have been investigated so far for the long-term load forecasting. However, because the electric loads consist of many complex factors, good forecasting has been very difficult. This paper proposes a long-term load forecasting method using a recurrent neural network (RNN). This is a mutually connected network that has the ability of learning patterns and past records. In general, when interpolation is used for unlearned data sets, the neural network provides reasonably good outputs. However, when extrapolation is used, such as in long-term load forecasting, some kind of tunings have been necessary to obtain good results. Therefore, to solve the problem, a method is proposed in which growth rates are used as input and output data. Using the proposed method, successful results have been obtained and comparisons have been made with the conventional methods. 相似文献
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分析了1000MW机组典型厂用电接线,计算机组正常运行状态和事故停机状态下厂用电的负荷。根据工艺流程的实际运行情况,探讨出安全停机时高压厂用备用变压器必须带的负荷,从而明确高压厂用备用变压器的容量设置。对《火力发电厂设计技术规程》中的条款“当发电机出口装有断路器或负荷开关时,高压厂用备用变压器的容量可按1台高压厂用工作变压器容量的60%~100%选择”提出修改意见,建议高压厂用备用变压器按1台高压厂用工作变压器容量的100%设置。 相似文献
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