Characterization of the module/array simulator using I-V magnifier circuit of a pn photo-sensor

In this paper, circuit design, dynamic response and photo-sensor temperature dependence of a 30 W module/array simulator circuit using an I-V magnifier circuit are described. By using a small photo-sensor in the circuit, the circuit was much simplified. Each gain of voltage and current was independently adjustable using the feedback control of the current signal. Simulator output power was controlled by an LED irradiation light which works like irradiation of sun light on real Si PV modules. The photo-current of the pn photo-sensor was below 100 micro ampere, hence, the current gain of the simulator needed more than 30 dB. The voltage gain was not more than 3 dB because a multi junction pn photo-sensor was used. The simulator output showed typical temperature dependence characteristics of PV modules by controlling photo-sensor temperature. The dynamic response of the short circuit current was measured and it was confirmed that the circuit has enough responsibility to apply the Maximum Power Point Tracking (MPPT) evaluation. A grand line of each module is isolated, hence any topology of connections is available. This circuit simplifies the control system and makes it easy to handle multi simulator units by one personal computer.