DC Power Supply for Solar Inverter Testing: PV Array Simulator Buyer's Guide

Why a flat DC supply isn't enough

A grid-tie inverter constantly hunts for the maximum power point of the array. To grade its tracker you must present a real photovoltaic I-V characteristic, the knee, the open-circuit voltage, the short-circuit current, and watch the inverter walk to the MPP. A standard DC supply holds a fixed voltage and tells you nothing about tracking quality.

A true PV / solar array simulator recreates the curve in real time and reshapes it as irradiance and temperature change. The NS91000 simulation option on the Ultra Power Systems N35500 platform generates these curves natively, so the inverter behaves exactly as it would on a rooftop or in a field array.

Standards your simulator must support

For results that satisfy auditors and customers, insist on the recognised test references:

• EN50530 static efficiency tests across irradiance and voltage points.
• EN50530 dynamic MPPT tests with rising and falling irradiance ramps.
• Sandia MPPT performance methodology for tracking-efficiency scoring.

The NS91000 covers EN50530 static and dynamic plus Sandia MPPT, and the underlying platform carries CE, IEC 61010, EN50530, IEEE 1547 and ISO 17025 references, so your lab data stands up to scrutiny.

Sizing voltage and power for string and central inverters

Match the simulator's open-circuit voltage ceiling to the inverter's maximum DC input, and its current to the array's short-circuit rating. With 0–2250 V available, the platform spans residential strings through 1500 V utility-scale architectures.

Power per channel reaches 42 kW in 3U, and master/master parallel scales to megawatt central-inverter test benches. The ≤5 ms response keeps the simulated curve stable as the inverter's tracker sweeps.

Automation and multi-channel MPPT testing

Modern inverters have several independent MPPT inputs; multi-channel simulation lets you stress each tracker with a different curve simultaneously, emulating partial shading and mismatched strings. LAN, RS232, RS485 and CAN with SCPI and Modbus-RTU let you script irradiance profiles, log tracking efficiency and integrate the simulator into your production or R&D ATE.

Power accuracy of 0.02% F.S. keeps your static efficiency points repeatable, while battery-side flexibility means the same chassis can later serve hybrid PV-plus-storage inverter testing without buying a second instrument. For high-power central inverters, master/master paralleling lets you build the simulated array up to the megawatt range while preserving a single control interface, so a production test cell can grow with your product line.

Tell us your inverter's DC window and channel count and we'll scope a fit, request a quote or email Ultra Power Systems.

Frequently asked questions