英语翻译The Wind Turbine and the Doubly-Fed Induction Generator

英语翻译
The Wind Turbine and the Doubly-Fed Induction Generator System
Operating Principle of the Wind Turbine Doubly-Fed Induction Generator
The power flow,illustrated in the figure called The Power Flow,is used to describe the operating principle.In this figure the followings parameters are used:
PmMechanical power captured by the wind turbine and transmitted to the rotorPsStator electrical power outputPrRotor electrical power outputPgcCgrid electrical power outputQsStator reactive power outputQrRotor reactive power outputQgcCgrid reactive power outputTmMechanical torque applied to rotorTemElectromagnetic torque applied to the rotor by the generatorrRotational speed of rotorsRotational speed of the magnetic flux in the air-gap of the generator,this speed is named synchronous speed.It is proportional to the frequency of the grid voltage and to the number of generator poles.JCombined rotor and wind turbine inertia coefficient
The mechanical power and the stator electric power output are computed as follows:
For a loss less generator the mechanical equation is:
In steady-state at fixed speed for a loss less generator and
It follows that:
where s is defined as the slip of the generator:
The Power Flow
Generally the absolute value of slip is much lower than 1 and,consequently,Pr is only a fraction of Ps.Since Tm is positive for power generation and since s is positive and constant for a constant frequency grid voltage,the sign of Pr is a function of the slip sign.Pr is positive for negative slip (speed greater than synchronous speed) and it is negative for positive slip (speed lower than synchronous speed).For super-synchronous speed operation,Pr is transmitted to DC bus capacitor and tends to rise the DC voltage.For sub-synchronous speed operation,Pr is taken out of DC bus capacitor and tends to decrease the DC voltage.Cgrid is used to generate or absorb the power Pgc in order to keep the DC voltage constant.In steady-state for a loss less AC/DC/AC converter Pgc is equal to Pr and the speed of the wind turbine is determined by the power Pr absorbed or generated by Crotor.The power control will be explained below.
The phase-sequence of the AC voltage generated by Crotor is positive for sub-synchronous speed and negative for super-synchronous speed.The frequency of this voltage is equal to the product of the grid frequency and the absolute value of the slip.
Crotor and Cgrid have the capability of generating or absorbing reactive power and could be used to control the reactive power or the voltage at the grid terminals.

风轮机和双重联邦机关归纳供电系统
风轮机双重联邦机关归纳发电器的Operating原则
The功率流,说明在称功率流的图,被用于描述操作原理.在这个图使用追随者参量：
PmMechanical力量夺取由风轮机和被传达给outputTmMechanical扭矩被申请于rotorTemElectromagnetic扭矩适用于电动子由磁性焊剂的rotorsRotational速度的generatorrRotational速度在发电器的rotorPsStator电能outputPrRotor电能outputPgcCgrid电能outputQsStator无功功率outputQrRotor无功功率outputQgcCgrid无功功率,这速度的空隙的被命名同步转速.它是比例与栅压的频率和与发电器poles.JCombined电动子和风轮机惯性系数的数字
计算The机械动力和定子电力产品如下：
For损失较少发电器机械等式是：
In稳定以损失的固定的速度较少发电器和
It跟随那：
where s被定义作为发电器的滑动：
The功率流
Generally滑动的绝对值比1,并且,因而,PR仅一小部分Ps低.因为Tm为发电是正面的,并且,因为s是恒定的频率栅压的正面和常数,PR的标志是滑动标志的作用.PR为消极滑动(速度了不起的比同步转速)是正面的,并且它为正面滑动(速度低比同步转速)是消极的.对于超级同步速度操作,PR被传达给DC公共汽车电容器并且倾向于上升直流电压.对于次同步的速度操作,PR被采取在DC公共汽车电容器外面并且倾向于减少直流电压.Cgrid被用于产生或吸收力量Pgc为了保留直流电压常数.在稳定损失的较少AC/DC/AC交换器Pgc与PR是相等的,并且Crotor吸收或引起的力量PR取决于风轮机的速度.电能控制如下将解释.
crotor引起的交流电压的The阶段序号为超级同步速度的次同步的速度和阴性是正面的.这电压频率与栅格频率和滑动的绝对值的产品是相等的.
Crotor和Cgrid有产生或吸收无功功率的能力,并且可能使用在栅格终端控制无功功率或电压.