Electric Power Systems 电力系统 Section 1 Introduction 第一节介绍 The modern society depends on the electricity supply more heavily than ever before. 现代社会的电力供应依赖于更多地比以往任何时候。 It can not be imagined what the world should be if the electricity supply were interrupted all over the world. 它无法想象的世界应该是什么，如果电力供应中断了世界各地。 Electric power systems (or electric energy systems), providing electricity to the modern society, have become indispensable components of the industrial world. 电力系统（或电力能源系统） ，提供电力到现代社会，已成为不可缺少的组成部分产业界的。 The first complete electric power system (comprising a generator, cable, fuse, meter, and loads) was built by Thomas Edison the historic Pearl Street Station in New York City which began operation in September 1882. 第一个 完整的电力系统（包括发电机，电缆，熔断器，计量，并加载）的托马斯爱迪生所建-站纽约市珍珠街的历史始于 1882 年 9 月运作。 This was a DC system consisting of a steam-engine-driven DC generator supplying power to 59 customers within an area roughly 1.5 km in radius. The load, which consisted entirely of incandescent lamps, was supplied at 110 V through an underground cable system. 这是一个半径直流系统组成的一个蒸汽发动机驱动的直流发电机面积约 1.5 公里至 59 供电范围内的客户。负载，其中包括完全的白炽灯，为 V 提供 110 通过地下电缆系统。 Within a few years similar systems were in operation in most large cities throughout the world. With the development of motors by Frank Sprague in 1884, motor loads were added to such systems. This was the beginning of what would develop into one of the largest industries in the world. In spite of the initial widespread use of DC systems, they were almost completely superseded by AC systems. By 1886, the limitations of DC systems were becoming increasingly apparent. They could deliver power only a short distance from generators. 在一个类似的系统在大多数大城市在世界各地运行数年。随着马达的弗兰克斯普拉格发展在 1884 年，电机负载被添加到这些系统。这是什么开始发展成为世界上最大的产业之一。在最初的直流系统广泛使用尽管如此，他们几乎完全被空调系统所取代。到 1886 年，直流系统的局限性也日益明显。他们可以提供功率只有很短的距离从发电机。To keep transmission power losses ( I 2 R ) and voltage drops to acceptable levels, voltage levels had to be high for long-distance power transmission. Such high voltages were not acceptable for generation and consumption of power; therefore, a convenient means for voltage transformation became a necessity. 为了保持发射功率损失（我 2 R）和电压下降到可接受的水平，电压等级，必须长途输电高。如此高的电压不发电和电力消耗可以接受的，因此，电压转换成为一个方便的手段的必要性。 The development of the transformer and AC transmission by L. Gaulard and JD Gibbs of Paris, France, led to AC electric power systems. 在发展的变压器，法国和交流输电由 L.巴黎戈拉尔和 JD 吉布斯导致交流电力系统。In 1889, the first AC transmission line in North America was put into operation in Oregon between Willamette Falls and Portland. 1889 年，第一次在北美交流传输线将在俄勒冈州波特兰之间威拉梅特大瀑布和实施。It was a single-phase line transmitting power at 4,000 V over a distance of 21 km. With the development of polyphase systems by Nikola Tesla, the AC system became even more attractive. By 1888, Tesla held several patents on AC motors, generators, transformers, and transmission systems. Westinghouse bought the patents to these early inventions, and they formed the basis of the present-day AC systems.这是一个单相线路传输功率为 4,000 公里，超过21 V 系统的距离。随着交流的发展多相系统由尼古拉特斯拉，成为更具吸引力的。通过 1888 年，特斯拉举行交流多项专利电动机，发电机，变压器和输电系统。西屋公司购买了这些早期的发明专利，并形成了系统的基础，现在的交流。 In the 1890s, there was considerable controversy over whether the electric utility industry should be standardized on DC or AC. By the turn of the century, the AC system had won out over the DC system for the following reasons: 在 19世纪 90 年代，有很大的争议或交流电力行业是否应该统一于直流。到了世纪之交的，在交流系统赢得了原因出在下面的直流系统为： （1）Voltage levels can be easily transformed in AC systems, thus providing the flexibility for use of different voltages for generation, transmission, and consumption. （1）电压水平可以很容易地改变了空调系统，从而提供了传输的灵活性，发电用不同的电压和消费。 （2）AC generators are much simpler than DC generators. （2）交流发电机简单得多比直流发电机。 （3）AC motors are much simpler and cheaper than DC motors. （三）交流电机和电机便宜简单得多，比直流。The first three-phase line in North America went into operation in 1893a 2,300 V, 12 km line in southern California. 前三个阶段的美国北线投产于 1893 年- 1 2300 五，南加州 12 公里路线研究。 In the early period of AC power transmission, frequency was not standardized. 在电力传输初期交流，频率不规范。 Many different frequencies were in use: 25, 50, 60, 125, and 133 Hz. 有许多不同频率的使用：25，50，60，125，和 133 赫兹。 This poses a problem for interconnection. Eventually 60 Hz was adopted as standard in North America, although 50 Hz was used in many other countries. 这对互连的问题。最后 60 赫兹标准获得通过，成为美国在北美，虽然是 50 赫兹在许多其他国家使用。 The increasing need for transmitting large amounts of power over longer distance created an incentive to use progressively high voltage levels. To avoid the proliferation of an unlimited number of voltages, the industry has standardized voltage levels. In USA, the standards are 115, 138, 161, and 230 kV for the high voltage (HV) class, and 345, 500 and 765 kV for the extra-high voltage (EHV) class. In China, the voltage levels in use are 10, 35, 110 for HV class, and 220, 330 (only in Northwest China) and 500 kV for EHV class . 较长的距离越来越需要大量的电力传输多激励他们逐步使用高压的水平。为了避免电压增殖数量无限，业界标准电压水平。在美国，标准是115，138， 161，和 230 千伏的高电压（高压）类，345，500 和 765 千伏级的特高