IS200ECTBG1A
功率调节和控制系统由一个逆变器构成，该逆变器将直流电转换为交流电，并通过逆变器内部的L-C滤波器控制输送到电网的输出功率的质量。用作静态开关的晶体管由开关信号控制，在简单的模式下，该信号将产生输出方波单相逆变器的L N原理方案为了获得尽可能正弦的波形，使用了一种更复杂的技术——脉宽调制（PWM）；PWM技术允许对输出波形的频率和r.m.s.值进行调节。光伏发电机提供的功率取决于其运行点。为了大限度地提高电厂的能源供应，发电机应适应负载，以便运行点始终对应于大功率点。为此，逆变器内部使用了一种称为大功率点跟踪器（MPPT）的受控斩波器；MPPT即时计算产生大可用功率的发电机的“电压-电流”对值。商用MPPT系统通过定期引起负载的微小变化来确定发电机特性曲线上的大功率点，从而确定电压-电流值的偏差，并评估新产品I x V是否高于或低于前一产品。在上升的情况下，荷载条件在所考虑的方向上保持变化。在另一种情况下，将以相反的方向修改条件。由于所需性能的特点，独立发电厂和并网发电厂的逆变器应具有不同的特性：•在独立发电厂中，逆变器应能够提供交流侧电压。在发电机产量和负荷需求变化时尽可能保持不变；•在并网发电厂中，逆变器应尽可能地再现电网电压，同时尽量优化和大化光伏板的能量输出

The power conditioning and control system is constituted by an inverter that converts direct current to alternating current and controls the quality of the output power to be delivered to the grid, also by means of an L-C filter inside the inverter itself. The transistors, used as static switches, are controlled by an opening-closing signal which, in the simplest mode, would result in an output square waveform. + - L N Principle scheme of a single-phase inverter To obtain a waveform as sinusoidal as possible, a more sophisticated technique – Pulse Width Modulation (PWM) – is used; PWM technique allows a regulation to be achieved on the frequency as well as on the r.m.s. value of the output waveform. The power delivered by a PV generator depends on the point where it operates. In order to maximize the energy supply by the plant, the generator shall adapt to the load, so that the operating point always corresponds to the maximum power point. To this purpose, inside the inverter a controlled chopper called Maximum Power Point Tracker (MPPT) is used; the MPPT calculates instant by instant the pair of values “voltage-current” of the generator at which the maximum available power is produced. The MPPT systems commercially used identify the maximum power point on the characteristic curve of the generator by causing, at regular intervals, small variations of loads which determine deviations of the voltage-current values and evaluating if the new product I x V is higher or lower then the previous one. In case of a rise, the load conditions are kept varying in the considered direction. In the other case, the conditions are modified in the opposite direction. Due to the characteristics of the required performances the inverters for stand-alone plants and for grid-connected plants shall have different characteristics: • in the stand-alone plants the inverters shall be able to supply a voltage AC side. as constant as possible at the varying of the production of the generator and of the load demand; • in the grid-connected plants the inverters shall reproduce, as exactly as possible, the network voltage and at the same time try to optimize and maximize the energy output of the PV panels