外文翻译--光伏并网逆变器

中文 1125字 译文 ： 光伏并网逆变器 最近，人们越来越关注的替代能源，因为化石燃料和核电厂的环境影响及其稳定性（长尾和原田， 1997 年 ; Myrzlk， 2001 年）。在各种替代能源中，太阳能发电尤为重视，除了因为它是一种清洁的，无限的能源，此外相当多的研究已经在这一领域取得了突出的成绩。太阳能发电系统由太阳电池组件，充电电池，和一个逆变器。现在只有逆变电流模式进入主流，原因是光伏逆变是正弦电流进入电网。具体体现在单相并网光伏逆变器中，它具有普遍的拓扑结构，这是标准的全桥电压源逆变器（电平逆变器），它可以创建一个正弦电网电流（ Kjaer et al., 2005; Kojabadi et al., 2006）。这种拓扑结构有两个普遍的问题如下。 （ 1 ）电池是 太阳能发电厂必不可少的储存电能设备。但电池充电是一个短期和有污染的过程，并且有负面经济的效率。然而，逆变器可以不使用电池可以解决这些问题。在这个过程中，接口电路为逆变环节的直流电（ DC ）输出的太阳能电池阵列的交流电源系统。如果输出电压的电流源逆变低于电力系统电压和在发生短路负荷或逆变器故障，它没有电流短路（ Myrzlk， 2001年） 。 （ 2 ）在一般的微处理器作为控制器，以实现良好的特点时，太阳能发电系统与电流源逆变器的设计。是在控制器以较少的价值，有高质量电感和电波的输出电流的高开关频率变频器 所需要的，但是，受限制的是开关损耗和处理器的采样频率。 图 .1 显示的结构电流源逆变器用作接口电路连接太阳能电池的实用线（ Mohan et al， 1995年） 。它由五个开关，一个电感器， LC 滤波器，输出端口。逆变器工作在这两个开关模式。质量保证开关只执行斩波行动，而第一季度，第四季度交换机确定方向的输出电压根据极性的电力系统。因此，与一般全桥 PWM逆变器执行完整的一块，该系统减少了开关损耗。 图 .2显示波形的传统电流源逆变器。它代表了波形的输出电压和电流，该电流通过电感，输入信号，每个开关。 图 .3显示了脉冲转变电流源逆变器电路，用于降低开关频率和提高效率。当太阳能电池模块输出电压的是高于或低于输出电压的转换器，则合成的电流源转换，这需要 Buck - Boost变换器运作良好。电路降压频率的逆变器是固定的，在60 HZ ，这是电力系统频率。该过滤器（ LS,CS）在输出端口的逆变器是一种低成本的能力，以改善波形的输出电流。如果过滤器的高容量的使用，功率因数的系统将不统一，因为相位延迟。 图 .4显示波形是电流源逆变器。指标代表交换期间的升压斩波器，这个数字。国际法协会， ILF代表波形电感电流 各自的转换和 IDC代表输出电流的逆变器。作为一个脉冲波形，输出波形的六脉冲移转换代表 6 波形开关频率 TS.We 采用了数字信号处理器（ TMS320F2812 ）产生的 PWM 6相移信号电流源逆变本文。由于采用非对称 PWM模式，波形的输出电流，这几乎是逆变器的波形相似，六乘以开关频率但不完全相同的。 图 .5 显示了各自的电感电流和输出电流的常规逆变器和逆变器相等的开关频率。 原文： Grid-connected photovoltaic system using current-source inverter Recently, there has been a growing interest in alternative energy sources because fossil fuel and atomic power plants affect the environment and its stability (Nagao andHarada,1997; Myrzlk, 2001). Among the various alternative source of energy, solar power stands apart as it is a clean and unlimited source of energy moreover, a considerable amount of research has been conducted recently in this field. A solar power systemconsists of a photovoltaic module,a charge battery, and an inverter. Only inverters operating in current-source mode are included in the classification,since one of the aims of the PV inverter is to inject a sinusoidal current into the grid. To embody the operation of a single-phase-grid-connected inverter for photovoltaic module,it has general topology that is a standard full-bridge voltage source inverter (VSI), which can create a sinusoidal grid current (Kjaer et al., 2005; Kojabadi et al., 2006). This topology has two general problem as below. (1) A battery is essential to store the electric energy generated by a solar power plant. But a charge battery has problems on its a short duration and pollution along with economic efficiency. However, transmitting the generated energy directly into the utility line without using a battery can solve these problems. In this process, an interface circuit called an inverter links the direct current (DC) output from the solar cell array to the AC power system. It does not matter if the output voltage of the current-source-inverter is lower than the power system voltage and in case of a shorted load or inverter malfunction, it does not have a surge current from a short-circuit (Myrzlk, 2001). (2) In general a microprocessor is used as the controller to achieve good characteristics when designing solar power systems with the current-source-inverters. In the controller, to reduce the value of the inductance and the ripple of the output current, a high switching frequency is required for the inverter, however, the frequency is restricted bythe switching loss and sampling frequency of a processor. Fig. 1 shows the structure of a current-source PWM inverter used as the interface circuit for linking solar cells to the utility line (Mohan et al., 1995). It consists of fiveswitches, one inductor, and an LC filter at the output port. This inverter operates in two switching modes. The QA switch only performs the chopping action, while the Q1Q4 switches determine the directions of the output voltage according to the polarity ofthe power system. Therefore, compared with general full-bridge PWMinverter that performs complete chopping, this system reduces the switching loss. Fig. 2 shows the waveforms of the conventional current-source PWM inverter. It represents the waveforms of the output voltage and current, the current through the inductor, and the input signals to each switch. Fig. 3 shows the proposed six-pulse-shift current-source PWM inverter circuit that is used to reduce the switching frequency and improve the efficiency. Whenever the output voltage of solar cell module is higher or lower than the output voltage of the converter in compositing the current-source converter, it is required that the buck-boost converter operate well. The proposed circuit has buck-frequency of the inverter is fixed at 60 Hz, which is the value of power system frequency. The filter (LS, CS) at the output port of the inverter is of a low capacity to improve the waveform of the output current. If a high capacity filter were to be used, the power factor of the system would not be unity because of the phase delay. Fig. 4 shows the waveforms of the proposed current source PWM inverter. TS represents the switching period of the buck-boost choppers in this figure. ILAILF represent the waveforms of the inductor currents of the respective converters and IDC represents the output current of the inverter. As a operational waveform, the output waveform of six-pulse-shift the converter represent six waveform in switching frequency TS.We used a DSP (TMS320F2812) to generate a PWM six-phase-shift signal for the current-source inverter in this paper. As a result of using the asymmetricPWM mode, the wa