关于three phase House + single Phase Solar System电工请入分分伺候

enhuichang · 发表于 2014-5-31 09:34:22

本帖最后由 enhuichang 于 2014-1-8 22:43 编辑
正打算装个3KW Single-phase的太阳能。发现家里的电表是3Phase的。而且还发现家里主要的用电大户（1.44KW的水泵和1.33kw的小空调）不是装在同一个火线（相位）上。问了几个装太阳能的答案都比较模糊。
问：如果把3KW的Single-Phase的太阳能装在1.44KW的水泵的火线（相位）上那么1.33KW的小空调是不是不能用太阳能发出来的电只能从政府购买？
大家帮我看下下面的补充的材料上不是说smart meter上的电不管哪相发出另外一相都能享受到太阳能？
补充：08/01/2014
Solar and 3 phase power
The Quick Answer
If you have 3 phase power, you HAVE to read the following paragraphs. Sorry, no quick and snappy answer this time. It's really important that you understand otherwise (a) you will waste a huge amount of your time on wild goose chases and (b) you may get tricked into paying more that you should and (c) you will be worried that solar is wrong for you.
The Western Power Rules
Until June 30th 2013 you are allowed to connect a 3kW inverter on a single phase, but after July 1st 2013 then the maximum automatically approved is 2.5kW and they have to perform a check on the "voltage rise" before they will approve anything larger than that (but they will NEVER approve anything larger than 3kW on a single phase). So if you want to install a 3kW solar installation after July 1st, then you can install 2 x 1.5kW inverters, 2 x 2kW inverters, 2 x 2.5kW inverters, but you cannot install a single 3kW inverter without waiting a week or two for them to complete their approval process.
Similarly, if you want a 5kW solar installation, you can install 2 x 2.5kW inverters, but you cannot install a single 5kW inverter unless it happens to be a 3 phase inverter (we sell the SMA Sunny Tripower 5kW 3 phase inverter, and the JFY 5kW 3 phase inverters).
How can having one or two single phase connected inverters cover my use across all three phases?
Firstly, this is how Western Power officially describes it...
"The 3 phase meter measures the combined consumption and generation across all three phases continuously - it does not distinguish between phases and then takes the net after a set period (of 10 minutes). If there is excess generation on one phase, and a load on another phase, then the excess generation will supply that load. If there is still more power required, then the customer will receive electricity from the network and it will be recorded in the meter as purchased/imported electricity. But if there is still excess generation after supplying all of the household load, it will be sent out onto the network and recorded as sent out (or exported onto the network), which is where the customer receives REBS and/or FiT (or neither if they aren't eligible)."
Did you understand that?
No?
What they are saying is that ALL the solar power generated on ANY of the three phases is sent to the meter first and ALL the power sent from the grid to the house on ANY phase goes to the meter first, and then every ten minutes, the meter does a calculation. If the solar made more power than the house demanded in that ten minute period, then there is a 'surplus' and you are paid for that surplus (currently 8.4c per unit inc GST), and if the house used more than the solar made, then there is a deficit and you will have to pay for the power (currently 24.8c per unit inc GST)
e.g
Let's say in a ten minute period, the solar with two inverters, one connected to the red phase and the other connected to the blue phase, made 1 unit of power. In the same ten minute period, with the air con, pool pump, oven and a TV running, the house used 3 units of power, then the meter subtracts the solar (1) from the power used (3) and records that you owe them for 2 units of power. It doesn't matter in the slightest what phase(s) the solar is connected to, the meter ignores phases entirely and calculates on the total across all phases.
or...
The Solar made 1unit of power and the house used 1unit , then that works out to zero. No money owed by you, no money owed to you by Synergy.
or...
The Solar made 1 unit, and the house used absolutely none in that ten minute window of time, then Synergy will pay you 8.4c

I'm still confused...do I need a 3 phase inverter or not?
Don't worry if the explanation above left you in the same cold sweat as Mrs McDonald's Year 6 maths class.
The short and simple answer is NO. You do not need to install a 3 phase inverter in Western Australia because the meter does all the work. If you are still uncomfortable with that answer, then you CAN install a 3 phase meter...see next paragraph.
3 Phase Inverters
SMA and JFY both have 3 phase inverters suitable for residential use (SMA Sunny Tripower STP 5000TL-20 from SMA and Suntree 5000TL from JFY). These inverters fall within the 5kW cap imposed in Western Australia for residential customers to obtain a payment for surplus power produced and exported back to the grid. Both are dual tracking inverters. The SMA model costs a little over $2,200, the JFY about $1800. Compare this to the price of 2 x 2.5kW Delta inverters at $1700 and they are quite respectably priced. We expect to see many more 3 phase 5kW inverters coming onto the market soon. If you want a 3 phase inverter, we sell both models, but suggest the SMA model is a better quality unit.
From:http://www.solar4ever.com.au/3phase.php