交流发电机

In this paper, the mathematic model of a. c. excited generator system based on field-oriented control is established first. The simulated results operating at no-load and steady state are agreed with the test waveforms by means of 2. 8kW ACEG prototype developed by Harbin institute of large electrical machinery and Zhejiang University.

本文建立了磁场定向控制交流励磁发电机系统的数学模型，并采用哈尔滨大电机研究所和浙江大学联合研制的2.8kW ACEG系统实验原理样机，测试。。。

The AC-DC-AC voltage source inverter main circuit and TMS320LF2407 are selected to form high performance alternating current excitation system of ASG in this dissertation after detail schemes argumentation.

本论文在详细方案论证的基础上选择了交－直－交电压型主电路和数字信号处理器TMS320LF2407构成高性能的异步化同步发电机交流励磁系统。

A new method to measure the mechanical angular acceleration of rotating system is established by changing the exciting mode of AC asynchronous tachogenerator,and form a angular acceleration tachogenerator to measure the mechanical angular acceleration directly.

摘 要：提出的旋转系统机械角加速度直接测量方法通过对交流异步测速发电机励磁方式的改变，构成了能直接测量机械角加速度的测旋转角加速度发电机。

A new method to measure the mechanical angular acceleration of rotating system is established by changing the exciting mode of AC asynchronous tachogenerator, and form a angular acceleration tachogenerator to measure the mechanical angular acceleration directly.

提出的旋转系统机械角加速度直接测量方法通过对交流异步测速发电机励磁方式的改变，构成了能直接测量机械角加速度的测旋转角加速度发电机。

The stability of AC-excited generator is studied on the detail analysis of the math equation and basic characteristic of it.

本文在详细分析交流励磁发电机的数学模型和基本特性的基础上，对其稳定机理进行了深入的研究，得到了其在不同转差下静态稳定性的规律及具有更高的暂态稳定性的理论依据，进行了仿真和实验验证。

The design of Brushless synchronous AC generator constitute of the main generator AC excitor revolve selenium rectifier and so on.

无刷同步发电机主要由主发电机、交流励磁机、旋转整流器组成。

This thesis calculates emphases the excitor circult of AC excitor .but the calculate of excitor circult must solve two problem: how to caculate the output AC phasic potential, phasic electric current and the capacity of AC excitor basing on the main generator direct current excitating voltage and direct current excitation current ;how to caculate the armature feedback, power factor and required ampere-turn of AC exciter.

本文重点对交流励磁机的磁路进行计算，但磁路计算先要解决两个问题：如何根据主发电机给定的直流励磁电压和直流励磁电流计算出交流励磁机的输出交流相电势，相电流及交流励磁机容量；如何计算交流励磁机的电枢反应，功率因数及其所需的安匝数。

Then introduce the principle of work and the construction characteristic. This thesis calculates emphases the excitor circult of AC excitor .but the calculate of excitor circult must solve two problem: how to caculate the output AC phasic potential, phasic electric current and the capacity of AC excitor basing on the main generator direct current excitating voltage and direct current excitation current ;how to caculate the armature feedback, power factor and required ampere-turn of AC exciter.

本文重点对交流励磁机的磁路进行计算，但磁路计算先要解决两个问题：如何根据主发电机给定的直流励磁电压和直流励磁电流计算出交流励磁机的输出交流相电势，相电流及交流励磁机容量；如何计算交流励磁机的电枢反应，功率因数及其所需的安匝数。

The high-voltage transmission was need for the case electrical power is to be provided at considerable distance from a generating station.

这种限制是由于换向器必须纠正内部产生交流电压，从而使大型直流发电机不可行的。

The mathematic simulation software compiled by this paper has been used to simulate the basic characteristics of the main parts of the aircraft ac EPGS, include the permanent brushless dc generators , the exciters with rotating rectifiers, the brushless ac generators, the brushless dc generators, the inverters and the automatic voltage regulators .

运用本文建立的数字仿真软件对飞机交流电源系统的主要部件，包括永磁无刷直流发电机、旋转整流励磁系统、无刷交流和直流发电机、逆变器和调压器的基本特性进行了研究。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。