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Power electronic inverters for photovoltaic (PV) systems over the years have trended towards high efficiency and power density. However, reliability improvements of inverters have received less attention. Inverters are one of the lifetime-limiting elements in most PV systems. Their failures increase system operation and maintenance costs, contributing to an increased lifetime energy cost of the PV system. Opportunities exist to increase inverter reliability through design for reliability techniques and the use of new modular topologies, semiconductor devices, and energy buffering schemes. This paper presents the implementation and design for reliability for a GaN-based single-phase residential string inverter using a new topological and control scheme that allows dynamic hardware allocation (DHA). In the proposed inverter architecture, a range of identical modules and control schemes are used to dispatch hardware resources within the inverter to variably deliver power to the load or filter the second harmonic current on the DC side. This new approach more than triples the lifetime of GaN-based inverters, reducing system repair/replacement costs, and increasing the PV system lifetime energy production.
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Inverter-based Emulation of Single-phase Air Conditioner Loads
Laboratory experimentation of electromechanical systems can be challenging from a practical perspective and offers limited flexibility once built. Aiming at maximizing versatility and accelerating laboratory research, we propose a method of electric motor emulation via power electronics. This paper is focused on constant-frequency air conditioners based on single-phase induction machines and we show how to control a single-phase inverter to emulate the ac-terminal dynamics of such a system serving thermal loads. This approach offers a convenient method of high-bandwidth air conditioner load emulation without moving parts. Such a setup could be used to realize electrical experiments that mimic residential load dynamics with high fidelity. After outlining the system model, we propose a practical voltage-source inverter implementation and conclude with experiments on a 600 W converter.
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- PAR ID:
- 10488593
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- Energy Conversion Congress and Exposition
- ISBN:
- 979-8-3503-1644-5
- Page Range / eLocation ID:
- 3069 to 3076
- Subject(s) / Keyword(s):
- Constant-frequency air conditioners, single-phase induction machine, dynamic emulation, current control
- Format(s):
- Medium: X
- Location:
- Nashville, TN, USA
- Sponsoring Org:
- National Science Foundation
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