共查询到18条相似文献,搜索用时 171 毫秒
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针对无刷励磁发电机转子绕组引出方式为固定引出转子的负端而无法运用乒乓式一点接地保护的问题,对乒乓式转子接地保护进行改进,提出采用单端注入直流电压源的乒乓式转子接地保护方式并给出改进的乒乓式转子接地保护方法。采用MATLAB/Simulink软件进行转子一点接地故障仿真模型试验,仿真结果表明,单端注入直流电压源的乒乓式转子接地保护能够满足无刷励磁发电机实际运行需要的精度和灵敏度。 相似文献
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无刷励磁发电机通常采用单端注入式原理构成转子一点接地保护,针对该保护无法计算接地故障位置的问题,提出采用自动举刷方式改变转子绕组的引出方式(由固定负端引出变更为正负两端均引出),进而采用双端注入直流电压的乒乓式原理构成转子一点接地保护.给出了改进的乒乓式接地保护原理、接地电阻计算方法和保护动作判据,并采用Matlab/Simulink软件构建转子一点接地故障仿真模型.仿真试验结果表明,改进的乒乓式转子特地保护能够满足无刷励磁发电机实际运行需要的精度和灵敏度. 相似文献
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无刷励磁发电机通常采用单端注入式原理构成转子一点接地保护,针对该保护无法计算接地故障位置的问题,介绍了双端注入式转子接地保护原理、接地电阻计算方法和保护动作判据,并采用Matlab/Simulink软件构建转子一点接地故障仿真模型。仿真试验结果表明,双端注入式原理能够满足无刷励磁发电机实际运行需要的精度和灵敏度。 相似文献
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针对发电机励磁回路接地保护中广泛使用的乒乓式发电机励磁回路一点接地保护的缺陷,叠加一方波装置进行改进,提出了一套全新、完整的一点接地保护方案,消除了原保护装置在发电机停机或无励磁空转状态的缺陷。 相似文献
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论述了乒乓式转子一点接地保护的原理改进方案,通过叠加辅助的直流电源,消除了该保护在发电机停机或无励磁空转状态不能检测发电机转子绕组接地故障的缺憾。 相似文献
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论述了乒乓式转子一点接地保护的原理改进方案。通过叠加辅助的直流电源,消除了该保护在发电机停机或无励磁空转状态不能检测发电机转子绕组接地故障的缺憾 相似文献
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针对发电机实际运行中所出现的励磁回路一点接地故障情况,讨论了一种发电机转子一点接地变电桥式微机保护方案,推导了计算接地电阻及接地点位置的数学方程。通过其灵敏度的理论分析并考虑实际问题,确定了一种较为合理的电路结构,给出了保护的实现方法和改进措施,提高了保护的灵敏度及可靠性。 相似文献
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Kenji Inoue Hideo Yamashita Eihachiro Nakamae Takayuki Fujikawa 《Electrical Engineering in Japan》1993,113(8):101-115
This paper describes principles together with analytic and experimental studies of an exciterless, brushless, and self-excited three-phase synchronous generator which was devised by authors. Since traditional brushless and dc self-excited three-phase synchronous generators without exciter did not have the self-exciting function by series characteristic component proportional to the load current inside the generator, they need auto-voltage regulating equipment or a transformer with three windings and condensers to obtain constant voltage characteristics. It also has the following problem in the case of two-pole traditional generator: oscillatory tension is generated at the shaft of the rotor caused by the magnetic force between magnetic poles of stator and rotor windings, and it causes mechanical vibration and noise. This paper proposes a new brushless and self-excited three-phase generator solving the aforementioned problems: the ratio of poles of the windings for providing power to load (armature and field windings) to the windings for supplying exciting power (stator and rotor exciting windings) is 1 to 5. Then oscillatory tension does not generate theoretically. Furthermore, a self-exciting three-phase generator using the 5th-harmonic component of armature reaction which makes series characteristic component proportional to the load current, currently is available. In this paper, the winding construction, the electric circuit, and the principle of the aforementioned generator are described, and the experimental results of the trial-produced generator show that the three-phase terminal voltage waveforms are almost sinusoidal and also balanced, and the voltage can be kept almost constant for the change of load. This generator has high reliability because of its simple construction. 相似文献
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It is desired from the viewpoints of maintenance and construction to make single-phase synchronous generators of brushless and self-excited types. A novel brushless and self-excited single-phase synchronous generator was devised by one of the authors. The stator exciting current is made to flow simultaneously with the load current in the armature winding. Thus, the iron core for the magnetic circuit can be both for the synchronous generator itself and for the exciter. Experimental studies of the brushless and self-excited single-phase synchronous generator of which the rotor winding is used as a rotor exciting winding and a field winding are described in this paper. In the proposed generator, the rotor is provided with a balanced two-phase field winding to improve the voltage wave distortion. The terminal voltage of this generator can be kept constant in spite of the load variation. Therefore, the proposed synchronous generator can be expected to be used widely. 相似文献
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双馈风力发电系统故障特性及保护方案构建 总被引:6,自引:0,他引:6
针对双馈电机励磁方式的特点,本文分析了电网发生故障时定子短路电流呈现的"多态"故障特征,论述了故障点距离、Crowbar保护动作门槛值以及励磁逆变器控制系数等因素对双馈电机短路电流特性的影响,并进行了仿真验证。基于以上研究结果,从提高双馈电机故障穿越能力的角度出发,提出了一套适用在风电场并网节点处的新型复合式电流—电压保护方案。通过对传统电流保护的改进和构建低电压穿越运行特性的电压保护,使其能够适应双馈电机的故障特征,满足风场联络线上故障的可靠切除及配电系统内故障时风电场的低压穿越运行,对实现含双馈风电机组的电网稳定及故障后的快速恢复具有重要意义。 相似文献
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对一起因发电机励磁电压故障录波回路虚焊引起的注入方波电压型转子接地保护动作进行分析,认为由于转子对地电容的存在,当模拟接地位置α变化时,注入方波电压型转子接地保护的计算公式已不再适用,并从设计、应用等方面提出了改进建议。 相似文献