是什么导致了电源干扰？
发布时间：
2021-01-06 15:50
来源：
是什么导致了电源干扰？
There’s a tenaciously prevailing opinion that mains-related problems can essentially be traced back to the power utility. This assertion is only partially correct. The truth is far more complex. Sources of power disturbances can be found at the power utilities as well as at the facilities of the power consumers. However, 85% of all power quality disturbances are indeed “homemade”, i.e. caused by the equipment operators themselves.
有一种普遍观点认为电源相关的问题基本上都可以追溯到公共电网。这种观点仅部分正确。真相要复杂得多。电源干扰的来源可以在共用电网和电力消费者的设施中找到。然而，85%的电能质量干扰事实上是“自制的”，例如，设备操作员自身造成的。
Power Utilities
公共电网
Under certain circumstances, connecting and disconnecting large loads on the part of the power utility may result in voltage fluctuations (i.e. overvoltage or undervoltage) or frequency fluctuations in the dynamic network. This mains pollution spreads throughout the entire grid and influences the functioning of sensitive devices such as rectifiers, networks and PLC systems.
在某些情况下，在公用电网上连接和断开大负载可能引起电压波动（例如过压或欠压）或动态网络的频率波动。这种电源污染扩散到整个电网并影响敏感设备的功能例如整流器、网络和PLC系统。
Operating Equipment (consumers)
操作设备（消费者）
Harmonics are caused by non-linear consumers such as thyristors, IGBTs and varistors. These components are used in, amongst other devices, DC power supplies (power packs), computers, electronic ballasts and dimmers, as well as in power converters and frequency converters for drive units using motors with adjustable speed. Modern electronics works with extra-low voltage. Incoming alternating current is first of all rectified by means of a bridge rectifier and smoothed by a smoothing capacitor.
谐波由非线性消费者（例如晶闸管、IGBT和压敏电阻等）引起，这些组件用在其他设备中，直流电源（电源组）、计算机、电子镇流器和调光器，以及使用可调节速度的电机的驱动单元的功率变流器和变频器。现代电子器件在超低电压下工作。进入的交流电首先通过整流桥进行整流，并通过平滑电容器平滑
Current consumed by these devices is pulsed. This results from intermittent charging of the smoothing capacitor downstream from the rectifier. The current’s waveform is changed by this intermittent charging: it’s no longer sinusoidal but rather superimposed with harmonic current. The consequence for the consumer is that sinusoidal current is no longer available from the mains.
这些设备消耗的电流为脉冲。这是由于整流器下游的平滑电容器的间歇性充电的结果。电流的波形被这种间歇性充电改变：它不再是正弦，而是用谐波电流叠加。对消费者来说，其后果是电源再也没有正弦的电流可用。
Due to the fact that voltage and current frequencies are linked via line impedance, they cause current and voltage distortion at the terminals and vice versa. If current supplied to linear consumers is not distorted, i.e. if it’s sinusoidal, and if the voltage has a different waveform, i.e. not sinusoidal, the current at the mains terminals is also non-sinusoidal. The following table describes the various phenomena and their causes.
由于电压和电流的频率与线路阻抗关联，它们会导致终端的电流和电压失真，反之亦然。如果提供给线性消费者的电流没有失真，即，如电流为正弦且电压具有不同的波形，即不是正弦，则电源终端处的电流也是非正弦。下表描述了各种现象及其原因
| Phenomenon 现象 |
Primary Cause 主要原因 |
Can be Limited by 可以由……限制 |
|
| The Power Utility 公用电网 |
The Power Consumer 电力消费者 |
||
| Frequency fluctuation 频率波动 |
Load changes, generation failure 负载变化，产生失败 |
Yes 是 |
No 否 |
| Gradual voltage changes 平缓的电压改变 |
Load changes 负载变化 |
Yes 是 |
No 否 |
| Rapid voltage changes/ flicker 快速电压改变/闪变 |
Switching, special loads 开关、特殊负载 |
No否 |
Yes是 |
| Voltage asymmetry 电压不对称 |
Asymmetric loading of the phases 各相的负载不平衡 |
To some extent 在某种程度上 |
Yes是 |
| Harmonics and sub-harmonics 谐波和子谐波 |
Special devices 特殊设备 |
To some extent 在某种程度上 |
Yes是 |
| Signal voltages 信号电压 |
Data transmission 数据传输 |
Yes是 |
Yes是 |
| Direct current or voltage 直流电流和电压 |
Special devices (half-wave rectifiers) 特殊设备（半波整流） |
No否 |
Yes是 |
| Voltage dips and interruptions 电压跌落和中断 |
Faults in the power utility’s or the power consumer’s network (short-circuits, interruptions) 公用电网或者电力消费者的电网故障（短路、中断） |
No否 |
No否 |
| Temporary overvoltage 暂时过电压 |
Faults in the power consumer’s network, power resonance 电力消费者的电网故障，电源谐振 |
No / to some extent 否/在某种程度上 |
To some extent /yes 在某种程度上、是 |
| Transient overvoltage 瞬时过电压 |
Lightning, switching operations 闪电、开关投切 |
No否 |
No否 |
关键词：
相关文章
