Basic Linear-Mode Solar-Cell Simulators

The paper describes basic types of linear-mode power systems for simulating voltage/current characteristics of solar cells modules. Starting from a current source with a chain of diodes arranged in parallel (being the most simple equivalent circuit diagram of a solar power module) a very basic solar module simulator using a bipolar power transistor and based on the "amplified diode" concept is developed. Furthermore, this principle is modified utilizing a linear-mode series regulator in order to reduce the dissipated power at no-load condition. The paper includes a detailed description of the different operating principles, gives dimensioning guidelines and presents also measurement results taken from laboratory prototype systems.