hi all!
between the new job and not much wind lately, it has taken 2 weeks to get some testing done.
the weather man said 15kph winds this morning. i think it was more like 15-20kph winds ( 9-12.5mph )
i had lots of elements to work with, but ended up using just one of the elements out of the 6 that are in the 18kw 208 volt 3 phase duct heater insert i have. i rectified the output from the genny to the element. the genny will start on its own with 2 or 3 elements connected in series, but can barely move with just the one element connected to the rectifier. i allowed the genny to come up to approx 100 rpm then connected the element.
the one element measures 12.2 ohm resistance.
the genny measures 2 ohm resistance in the 1 circuit star conection.
it was designed for 240 volt output at 600 rpm 3 phase (12 pole)
the prop is 12 foot diam, designed from alton moore's blade program entered as a 2 blader tsr_7. 3 blades were made and mounted. it starts in almost unnoticable wind.
here is a pic of the portable rectifier assembly i use for testing.
these are different elements that i connected in star, and the picture after that are 3 elements connected in series. each of these elements are 2.2 kw at 208 volt. they were not used for the final testing today though.
this is the element bank i will be using for heating. it is 18kw, 208 volt, 3 phase. it has 6 elements and was originally connected 2 circuit deltal. the elements can all be connected individually. most of the testing today was done with just one element powered from my rectifier assembly.
with all the fluctuating going on, it was hard to try and right down the numbers from all meters. i simply lined up the meters from left to right and took pictures to get the readings. the meters are from left to right, frequency meter, dc volt, and amperage using 1 foot of #10 lead wire as a shunt.
240 rpm, 92.6 volt, 7.5 amp 695 watt
247 rpm, 99.8 volt, 8 amp 798 watt
196 rpm, 76.8 volt, 6.1 amp 468 watt
i also used to fly a 1.5 or 2hp 180 volt dc motor as a genny. i connected the output from the rectifier to the motor at 0 rpm and watched the motor climb in speed. it went well over 200 volt and prop was doing well over 600 rpm. i laughed to myself as the rpm of the motor increased in step with the voltage from the genny.
now the genny seems to be working fine, but i am not sure about the prop. i did this knowing that a 12 foot diam prop will likely be small for the genny. there is a slight bounce to the top guy cables, but seems to disappear after about 100 rpm. i am sure it is resonating somehow with the tower. the total balance over the rpm seems to also be good. i did not observe any furling throughout the testing.
i can make a ok genny and prop, but my mind does not do the best when it comes to looking at the overall performance of the whole unit. higher wind testing when time and weather allows will give a clearer picture of what i have here.
any analytical thoughts at this point from the very experienced would be greatly appreciated.
hope you enjoyed the update!
zubbly
