Part II system Introduction and System Selection
2.1 System Application Introduction
PV pumping system is mainly composed of solar panel components, PV inverter and PV water pump three parts. Solar module absorbs sunlight radiation energy, converts it into electric energy, and provides power supply for the whole system. The PV pumping inverter controls and regulates the operation of the system, uses the electric drive pump emitted by the solar cell array, adjusts the output frequency according to the change of sunshine intensity, realizes the maximum power point tracking and utilizes the solar energy to the maximum. The pump is driven by a motor and is used for water extraction from deep wells or rivers. Based on the design idea of storing electricity in the solar pumping system, the storage battery is not equipped, so as to simplify the system and reduce the cost.
PV Inverter is the core technology of the system .A pump that drives a AC motor, need to use the following two functions of the inverter: 1) Inverter function-the solar cell array output DC conversion to alternating current; 2) maximum power point tracking (MPPT) function--adjust the output frequency according to the illumination intensity in real time, guarantee the system output maximum power. Photovoltaic pumping system to water storage in place of the economic and environmental protection concept of storage, without energy storage batteries, solar energy as the driving force directly drive the pump motor work, greatly saving the system construction and operation costs. Through MPPT core technology, the system provides stable water resources for watering. Greatly improved the agricultural economic benefits, and improved the ecological environment. The technology of environmental protection and energy saving, reducing greenhouse gas emissions, is conducive to promoting photovoltaic water conservancy industry and the global economy, environmental sustainability.
2.2 PV Pump System advantagesPV water pump system consists of solar cell array, pumping inverter and water pump, save energy storage device such as battery, to water storage instead of storage, direct drive pump pumping, high reliability, and greatly reduce the cost of construction and maintenance of the system. 1), Features
◆Pumping system fully automatic operation, no manual and only a small amount of daily manual maintenance.
◆All equipment are equipped with IP65 protection level, all-weather work, no need to build batteries or control rooms.
◆With high efficiency and weak light work function, in cloudy weather can still play a high efficiency, to ensure cloudy and cloudy water.
◆MPPT control technology and new inverter technology to ensure the maximum efficiency of the system using solar power.
2), Advantages Compared with traditional power lift irrigation, solar lift irrigation technology has three advantages: First, the operating cost is small. The solar lift irrigation station basically does not have the matching facility demand, but the power lift irrigation station must support the transmission and transformation facility, the average cost of about 10.15 million yuan per kilometer. In addition, the solar energy lift irrigation station can realize no energy consumption, unmanned operation, can save daily water consumption and labor costs 90%. Second, energy-consuming emissions are low. Reduce the power, diesel and other energy consumption. Every 1 degrees of electricity savings, the corresponding savings of 0.4 kg Tce, effective reduction of carbon dust, carbon dioxide, sulfur dioxide and other emissions. The third is the high efficiency of water extraction. For small and medium sized pumps, solar dedicated pumps can increase efficiency more than 40%. Agricultural photovoltaic irrigation system in the absence of electricity, can fully use photovoltaic technology to solve agricultural irrigation, rural drinking water problem, its initial investment is not only far less than long-distance erection of transmission lines, continuous operation three years after the comprehensive cost is lower than diesel generators. Photovoltaic water pump system is an effective exploration of the development of new energy technology, which can effectively solve the problems of drinking water and irrigation water shortage in the area of electricity shortage. PV water pump system can be widely used in "agricultural irrigation", "Desert Management", "Grassland animal husbandry", "urban Water Features", "Life-use", and other fields.
2.3 Selection of PV pump
1: System head Calculation: (1): Pump Down depth H1 (2): Water pipe Transport Distance L1 (3): Water tank from the ground height H2
Head calculation: H total = (h1+h2+l÷100)
(L length per 100 meter conversion One meter lift) 2: Sunrise Water Calculation According to the hourly demand * Local average sunshine time can be seen in Schedule 1 the average Sunshine time table and installation angle of the major cities . 3: According to 1.2 Select pump model * To ensure the optimal operation of the system recommended pump selection when the lift to retain 10%-15% allowance.
2.4 PV Pump Inverter selection(One) PV Pumping Inverter Power range: Standard product ①1hp/3hp 220V 750-2.2kw ②3HP 380V 0.75-710kw Customizable single-phase/three-phase 220V high-power pumping inverter. Configuration principles: ① Installation location elevation: Less than 2000 meters above sea level of 1000 meters above the elevation of 100 meters per increase in the rated output current reduction of 1% . ②: According to the pump rated current selection of the rated current of a high profile inverter such as: Elevation 3000M 380V 7.5KW rated current 13A pumps Plus the rated output of 2000 meters altitude to reduce the actual rated output current 15.2A plus inverter recommended to enlarge the first gear, then you need to choose 11KW Inverter .
2.5 Selection of auxiliary equipment(One) Output reactor: When the inverter to the pump connection line distance of more than 100 meters, the proposed installation can inhibit high-frequency vibration output reactor, to avoid motor insulation damage, leakage through the large and inverter protection frequently. (Two) DC Circuit breaker ①Input voltage 1000 VDC ② Current selection According to the short circuit current (ISC) * Parallel logarithm * (1.8~2.2) of each battery panel to select the corresponding circuit breaker . (Three) PV DC Lightning Protection device ①SPD working voltage selection: ≥ system operating voltage 1.3 times times
②SPD Type: 2 Class Lightning protection Combiner box: 2-16-Way input output:1 Road can be customized ① battery string maximum input voltage: Dc1000v ② Battery Series Input current: 10a ③ input back: According to the requirements of ④ fuse rated current: 11A (Five) Water level sensor ① Switch Type ② analogue type (0-5v/0-10v/4-20ma)
2.6 Selection of solar panels
The PV panels of each group are used in parallel in accordance with the required power requirements. The power of the solar panel is recommended to use the appropriate pump rated power of 1.3-twice times (pump voltage of 380V) or 1.6-twice times (pump for single/three-phase 220V). The specific configuration should be based on the system requirements of water flow design. For example: The selection of 380v/1.5kw pumps, 100w/18v PV panels, PV panels installed as follows: According to the table 380V 18V PV Panels selected 30 block series use, series power for 30*100=3000w. Solar panel selection power range of 2.25 kw~ 3.0KW. Therefore, the proposed number of parallel 1 groups. Selection of 220v/1.1kw pumps, 200W/36V PV panels, PV panels installed as follows: According to the table 220V 36V PV Panels ,selected 9-10 block series use, series power for 10*200=2000w. Solar panel selection power range of 1.8 kw~ 2.0KW.
2.7 Battery Plate Bracket selection
(polycrystalline/single crystal) See section III, third subsection, solar array installation