500W光伏离网系统方案

客户的用电需求 ：照明20W灯具3盏，平均每天工作5小时，电视机50W，平均每天工作4小时。地点为内蒙内某牧民家。

需求分析： 负载总功率为110W，都为阻性负载，平均每天用电为0.5度。

设备选型： 根据负载的类型和功率，选用12V20A的PWM控制器和500W修正波逆变器，组件采用一块320W的单晶组件，蓄电池采用一块12V100AH的铅酸蓄电池。控制器、逆变器和蓄电池做成一体化柜子，方便携带。

5kW光伏离网系统方案

客户的用电需求 ：照明200瓦每天工作6小时，冰箱50瓦每天工作24小时，两台一匹空调工作12小时，电视机50瓦每天工作10小时。还有洗衣机，台式电脑，电饭锅，电风扇等家电，客户安装地点在四川凉山。

需求分析： 首先统计负载总功率：照明200W、冰箱50W、空调1500W、电视机50W、洗衣机算300W、台式电脑200W、电饭锅1200W、电风扇100W，总计3600W。再统计每天用电量：照明1.2度电、冰箱1.3度、空调5度、电视机0.5度、洗衣机算1度、台式电脑0.5度、电饭锅1度、电风扇0.5度，平均总计 11度，大部分用电都是在晚上，约8度左右。

系统设计： 负载总功率为3.6kW，因此选用5kW功率的逆变器，给空调启动留有余量；四川凉山光照条件较好，平均每天算4小时，设计选用3.8KW的组件，平均每天能发电 15度，离网系统效率较低，一般约0.8，平均每天可用电12度，因此基本上可以满足99%以上的用电需求；蓄电池设计为 10度电，满足正常天气的用电需求，因为客户预算有限，不考虑阴雨天和冬天光照不好的天气情况。

设备选型： 选用古瑞瓦特SPF 5000ES控制逆变一体机，输出功率为5KW，组件采用10块单晶380W的组件，采用8块12V150AH铅酸蓄电池。

电气方案： 10块组件全部串联，接入逆变器光伏输入端，8块12V150AH铅酸蓄电池，采用4串2并的方式接入逆变器的蓄电池输入端。电气图如下：

500W photovoltaic off-grid system scheme

Customer's electricity demand: 3 lamps with 20W lighting, working 5 hours a day on average; TV with 50W, working 4 hours a day on average. The place is a herdsman's home in Inner Mongolia.

Demand analysis: The total power of the load is 110W, all of them are resistive loads, and the average daily electricity consumption is 0.5 degrees.

Equipment selection: Based on load type and power, 12V20A PWM controller and 500W correction wave inverter are selected, 320W single crystal components are used as components and 12V100AH lead-acid battery is used as storage battery. Controller, inverter and battery made into an integrated cabinet, easy to carry.

The picture

The picture

5kW photovoltaic off-grid system scheme

Customer's demand for electricity: Lighting 200 watts working 6 hours a day, refrigerator 50 watts working 24 hours a day, two one-piece air conditioning 12 hours a day, TV 50 watts working 10 hours a day. As well as washing machines, desktop computers, rice cookers, electric fans and other household appliances, the customer installed in Liangshan, Sichuan.

Demand analysis: First count the total load power: lighting 200W, refrigerator 50W, air conditioning 1500W, TV 50W, washing machine 300W, desktop computer 200W, rice cooker 1200W, electric fan 100W, a total of 3600W. The daily electricity consumption is as follows: 1.2 KWH for lighting, 1.3 KWH for refrigerators, 5 KWH for air conditioners, 0.5 KWH for TV sets, 1 KWH for washing machines, 0.5 KWH for desktop computers, 1 KWH for rice cookers and 0.5 KWH for electric fans. The average total is 11 KWH. Most of the electricity consumption is at night, about 8 KWH.

System design: The total power of the load is 3.6kW, so the inverter with 5kW power is selected to leave enough for the start of the air conditioning. Sichuan Liangshan light condition is good, the average day is 4 hours, the design uses 3.8KW components, the average daily power generation 15 degrees, off-grid system efficiency is low, generally about 0.8, the average daily available electricity of 12 degrees, so basically can meet more than 99% of the demand for electricity; The battery is designed to produce 10 kilowatt hours of electricity to meet the demand in normal weather. Because the customer's budget is limited, the rainy day and the bad illumination in winter are not considered.

Equipment selection: Guruwatt SPF 5000ES is selected to control the inverter all-in-one, with the output power of 5KW, 10 single-crystal 380W components and 8 12V150AH lead-acid batteries are used.

The picture

Electrical scheme: All 10 modules are connected in series to the photovoltaic input end of the inverter, and 8 12V150AH lead-acid batteries are connected to the battery input end of the inverter by means of 4 series and 2 parallel. The electrical drawing is as follows: