Programmable power supplies and loads are evolving to best serve a variety of applications as they leverage technologies such as wide-bandgap semiconductors, as described in our March special reports on the topics. Those reports focused on hardware, but software—ranging from simulation to instrument control—has a role to play as well.
MathWorks offers simulation and modeling tools for programmable power-supply design. “MathWorks provides Simulink software that lets engineers model digital control algorithms and the analog circuit together, before beginning detailed circuit design with a SPICE circuit simulator,” said Tony Lennon, market manager for power electronics control design.
Lennon identified a trend over the past year toward advances in hardware-in-the-loop (HIL) testing.1 “HIL testing helps engineers validate the control software they program on a microcontroller or FPGA,” he said. “The HIL test system consists of a computer with appropriate I/O that runs the analog components as a real-time simulation.” The real-time simulation model consists of code generated from a model developed in Simulink and other software, he said, adding, “The benefit of HIL testing is that engineers can validate their control code for a full range of operating and fault conditions without damaging prototype power supplies.”
Lennon cited several challenges in power-supply design. “Power supplies are often required to operate in conditions with varying loads and sometimes fluctuating power inputs,” he said. “Simulink lets engineers design their digital control algorithms in models where these varying conditions can be simulated.” He pointed out that fault conditions can also be simulated. “Using simulation helps engineers uncover errors in their control algorithms before they move to prototype testing,” he said.
MathWorks serves a variety of application areas. “Simulink can be used to model most electrical systems, and the models can generate code that can be run as a real-time simulation,” Lennon said. “This means that engineers can begin validating the control code for their power supply against a real-time simulation of an electric-vehicle drivetrain, a solar-panel system, a microgrid, etc.”
Keysight Technologies offers a variety of software solutions, ranging from simulation to test automation. “Our PD1000A Power Device Measurement System for Advanced Modeling paired with our Advanced Design System (ADS) simulation solution enable thermal simulation of complex power-converter designs,” said Ryo Takeda, power semiconductor solution architect; Bernhard Holzinger, power semiconductor technical architect; and Mike Hawes, power solution consultant. The combination targets industries such as HEV and EV manufacturers who are migrating their power-conversion designs to wide-bandgap devices.
Bill Griffith, who works in product marketing at Keysight, commented, “Keysight’s DC power solutions combine custom hardware and software to solve industries’ toughest test challenges. Examples include IoT battery-life testing, photovoltaic (PV) string inverter testing, HEV/EV testing, and single- and 2-quadrant high-power testing with a regenerative power supply.”
He added that application-specific software allows high-performance power supplies to test a variety of devices. The software includes distributed solar array simulator control platforms for testing PV string inverters in real-world conditions as well as for implementing industry-standard test-automation strategies in accordance with the EN 50530 standard2 for PV inverter MPPT (maximum power point tracking) efficiency tests.
Specific Keysight offerings include the DG9000A advanced/multi-input PV inverter test software. “Distributed solar array inverters are difficult to test,” said Griffith. “Missing test points leads to an inaccurate representation of energy conversion.” Keysight’s DG9000A can test multiple input inverters and manage up to 12 separate MPPT operations simultaneously, he said.
The company also offers Solar Array Simulator (SAS) Control Pro as part of its BenchVue software, which automates static and dynamic EN 50530 MPPT test. Simply input the test parameters, and click “Start Test,” said Griffith, adding, “Once the test is complete, SAS Control Pro creates a report formatted to the EN 50530 standard.”
Griffith also said, “Keysight has formed an automotive and energy group to continue building DC power solutions with state-of-the-art hardware and software. Keysight PathWave Test 2020 software suite enables 5G, IoT, and automotive engineers and managers to streamline product development processes and facilitate rapid decision making.”
Finally, Tektronix's recently released I-V tracer software allows the Keithley 2400 Series Graphical SourceMeter instruments to behave as modern replacements to old Tek curve tracers like the 370 and 576, according to Wilson Lee, technical marketing manager, Americas. “We developed this software in collaboration with several customers to address needs in areas like failure analysis and incoming inspection, where benchtop instrument use and immediate feedback is a must,” he said. “One of the great benefits of the software is that it exists on the SMU itself, so you can easily transport a curve tracer around a lab under your arm!”
REFERENCES
1. Hardware-in-the-Loop Testing for Power Electronics Control Design, White Paper, MathWorks, 2019.
2. Overall efficiency of grid connected photovoltaic inverters, EN 50530, European Standards, 2010.