Among today’s various renewable energy sources, solar energy is by far the most prevalent. To harness this source, arrays or solar panels are formed by linking solar modules that contain semiconducting material which absorbs photons of sunlight. The photons energize electrons in the semiconducting material, freeing them from their atoms. This, in turn, creates direct current (DC) that must be converted to alternating current (AC). Photovoltaic (PV) technology is the mechanism used to implement this solar-to-electrical conversion. Unfortunately, it generally can only achieve efficiency of roughly 19 percent. The only way to maximize the use of harvested solar energy while minimizing module and system size is to achieve efficiency of greater than 95 percent.
There are two types of PV systems. The first type is configured as an off-grid or standalone system that operates independently of the electric utility grid. The second type of PV system can be integrated with the utility grid, which enables energy to be shared between the PV system and the grid. One benefit of this approach is that surplus power can be sold back to the utility.
Regardless of which approach is taken, each PV system uses similar components, including PV modules, a cooling system, an energy storage system or battery bank, the load, a utility grid interface, and a PV inverter system (see Figure 1). While these components vary depending on functional and operational requirements, the PV inverter system is the heart of any implementation. It performs all DC-to-AC conversion, power protection, monitoring, and control functions.
Figure 1: Typical PV energy system Click on image to enlarge
There are a number of decisions to make in the design of PV inverters, including power system interconnection regulations and international standards. Specifications such as IEEE 1547 and EN50160 impose constraints including the necessity for galvanic isolation, as well as the maximum harmonic distortion of the current injected at the point of common coupling (PCC), and the maximum permitted DC current injection.
Microsmi makes vry lo pwer FPGA device.
Misleading is the use of 1t,2nd,srd for efficiencyimprovements
the are all seperate and inependent issues.
MPPT input power otimization.
PWM, how any MPPT, PFC, PFM or PWM circuit works, it s the basis of all modern power conversion.
PFC = current propotionl to voltage... over fundamental period.
All must be used together to maxamize efficiency.
At a systems level, if you have any electrical storage in the system, you are best off to connect the panels and the batteries by DC, not AC. That typically results in 10% more energy available when you invert the AC out of the storage. (1. Eliminates a conversion: DC -DC - AC instead of DC - AC - DC - AC, and 2. higher end-to-end efficiency)
If by "prevalent" you mean installed capacity, then wind far outstrips solar. Latest numbers I saw were 238 GW for wind, 67 GW for solar. You also mention solar efficiency of 19% (that is a typical number for panels themselves) and then say we need 95% to "maximize use of harvested solar energy". I think you probably meant to say that just the inverter efficiency should target 95% since basic physics limits existing Si panel efficiency to about half that.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.