I hope this goes down well. The Fe frartenity has given me much to respect and in my old age regardless of previous issues and that I may rant from time to time, my love of this hobby still stirs me. The point is check out the hulls and buy what you want and put your power train mojo to work..Yes!...Life is too short
Alternating current can be transmitted long distances far more economically than direct current — direct current has taken decades to phase out of Manhattan because the early backbone of New York’s electricity grid was built by Mr. Edison’s company (1882), which had a running head start in the first decade before Mr. Tesla and Mr. Westinghouse demonstrated the potential of alternating current with the Niagara Falls power project.
Alternating current can be transmitted long distances far more economically than direct current — direct current has taken decades to phase out of Manhattan because the early backbone of New York’s electricity grid was built by Mr. Edison’s company (1882), which had a running head start in the first decade before Mr. Tesla and Mr. Westinghouse demonstrated the potential of alternating current with the Niagara Falls power project.
That is not entirely true. All your lines connecting individual power grids are high voltage DC lines. The lines going to your house are all AC lines.
Power plants in the USA are 60 hz, 3 phase, AC. It is to expensive to convert ac to dc or vice versa.
That is true but over long distances High Voltage DC lines have lower losses than AC lines do. The increased costs of the rectification of AC is offset by the lower losses of DC over longer distances.
Do you have any idea how large the rectifiers and FEts would have to be to do what you are saying??? We are talking about BILLIONS of watts being transported, just across Texas. Utilities use 3 phase transformers to step up the AC voltage (345000 volts) for low line currents creating low line losses in transporting electricity, then step it down on the remote end for lower voltage and high currents at the customers load.
Like I said it is not practical. It is mainly used for special applications like crossing bodies of water. Texas is building many new long haul "AC" lines ($5 billion cost) in the next 3 years to handle new wind generation coming from the panhandle.
ABB is a European (German) company. Europe does not have the benefit of having a long, single standard for the entire continent as we have here in the US. Conversion of power from AC to DC to AC is necessary for their power systems to interconnect, whereas for North America they all use the same standard frequency and voltages. HVDC makes sense at one point within wind plants because the rotational frequency of the turbine may change but the output frequency and phase needs to be consistent with the grid.
AC won out in America because it is more efficient for long-distance runs from the power plant to the consumer. In situations like local production/consumption (ie, solar or wind) then DC is better because you can store your excess power in batteries more easily, and have a single inversion point to convert to AC.
My previous employer was very involved in medium voltage DC (48V) distribution within data centers (AC in (anything from 120 to 480V) and DC (typically 48V) out), with local step-down in the racks to provide the 3/5/12V required by servers. After we built several test systems, Intel had the same "new idea" and started to push it for their equipment. The reason for the 48V system is that it is the standard for telcom backup power (the phone company runs on 48VDC) and the products are mature and well-understood.
Andy
BTW, 48V doesn't mean 48V at the phone company. It's actually about 54V, adjusted based on the temperature of the backup batteries. Lots of funny stories about engineering groups (within our company!) who spoke different languages both ethic and technical...
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