Development and Experimental Validation of a Compact I–V Curve Tracer and PWM/MPPT Load Simulator for PV Systems

Background

The global transition toward renewable energy has made solar photovoltaic (PV) systems a cornerstone of sustainable power generation. To train future engineers and researchers effectively, it is crucial to provide practical, hands-on laboratory setups that allow for the modeling, analysis, and testing of PV system behavior under various operational and environmental conditions.

At KTH, courses in renewable and photovoltaic energy already deliver a strong theoretical foundation. However, practical learning—particularly involving measurement and control of PV performance parameters—is equally vital. A compact and modular test rig that integrates an I–V curve tracer and an intelligent load simulator would provide students and researchers with the tools to study real-world PV characteristics, controller dynamics, and energy conversion efficiency.

I–V curve tracing is the fundamental method for characterizing PV modules, enabling the determination of key parameters such as short-circuit current (Isc), open-circuit voltage (Voc), maximum power point (MPP), and fill factor (FF). Complementing this with a PWM (Pulse Width Modulation) and MPPT (Maximum Power Point Tracking) load simulator provides a dynamic testing platform that can emulate realistic load conditions and evaluate system efficiency under varying solar irradiance and temperature conditions.

Aim of the Thesis

The goal of this thesis is to design, develop, and validate a compact Arduino-based I–V curve tracer integrated with a PWM/MPPT load simulator for use in the photovoltaic laboratory test rig at KTH. The system should be capable of performing automated I–V measurements, simulating DC loads via PWM, and implementing common MPPT algorithms (e.g., Perturb and Observe, Incremental Conductance) to dynamically track and test PV performance.

Specific Objectives

• Design and implement an I–V curve tracer for small- to medium- and full scale and multiple PV modules using Arduino-based control and measurement.

• Develop a PWM-controlled DC load simulator capable of variable resistive loading and controlled current sinking.

• Integrate MPPT algorithms to simulate real PV inverter/controller behavior and evaluate system tracking accuracy.

• Compare different I–V tracing methods (e.g., capacitive, electronic load, PWM sweep) and assess accuracy, speed, and cost trade-offs.

• Validate the complete system through laboratory experiments and compare results to existing commercial or reference instruments.

Expected Deliverables

• Final thesis report and presentation.

• Functional prototype of compact I–V curve tracer and PWM/MPPT load simulator.

• System design files (schematics, PCB layout, firmware).

• Experimental validation data and comparison with commercial instruments.

Duration

The project should start in Jan-Feb 2026, with a duration of up to 6 months.

Location

KTH, Department of Energy Technology

Main Supervisor

Examiner