Solar Energy Power Generation: Introduction Sky Resources Solar Technology Co., LTD----projects ManagementTraining document
Clarification of the Solar Energy Power Generating Following two type of the solar energy power generating • Grid-off solar energy power generating Main used in the area where is no electricity supply or the telecommunication station which is faraway from the electricity net or the wireless places. Key components：solar panel、battery、intelligent controller、inverter 、electricity distributionand anti-lighting system. (electricity distribution is close to the active load). Advantages：offer the independent electricity net which will not restricted by the local public electricity net. Disadvantages：much waste of the energy resources or can controller the use of the solar energy resources. the electricity use is high restricted by the weather condition, the low efficiency of use and high investment, a little low system life span (especially say the batter’s life span).
Grid-On PV System Main use in the place where the city electricity distribution net. It is the lead direction of New energy from home and all over the world. Key components:solar panel、grid-on inverter、 electricity distribution and anti-lighting system （much simple ). Advantages：high efficient use of the system，long life span；the investment cost is some lower；the use of the electricity will not restricted by the system itself and the weather conditioninfluence. Disadvantages：the return of the electricity powered by solar will be restricted by the local public electricity net.
The Independent Grid-off Solar Energy Power Generating System Detailed Introduction
Solar Panel/Module Solar Panel is a generating equipment which can transfer the solar light energy to the DC electricity energy. It is made as a single panel when use according to the different requirements on the power output and its voltage. It also can be used as several solar panel connected in series (which is to meet the demands on voltage) and connected in parallel (which is to meet the demands on current). this way can make as the panel/modules arrays to supply much higher electricity demands. the solar panel/modules has many advantages such as high power efficiency on area，long life span, and high reliability，during the use period, the loss of the output power is less than 20%. The structure of the silicon solar panel/ module
The features of Volt-Amperefor PV solar panel Generally speaking，the solar panel electricity generating is increased in percentage with the intensity of the sunlight. With the surface temperature increased of the solar panel slightly decreased. The so-called general of the solar panels that power is in the sunlight intensity of 1000 W/M2, components, surface temperature is 20 ℃, Imax * Umax value.
Photovoltaic module installation angle Photovoltaic module installed inclination should be guaranteed to receive the maximum sunlight exposure, in normal circumstances components and the horizontal direction for the local latitude ± 5 °to 10 °. That is, when the reduction in the summer, when the increase in the winter. If a fixed angle brackets, the use of local latitude tilt angle. For example, the city of Shantou to 23.42 °latitude.
Battery discharge curves • 10 hour rate (0.1 CA), 5 hour rate (0.17 CA), 3 hours rate (0.25 CA) discharge termination voltage: 10.8 V /set; 1 hour rate (0.55 CA) discharge termination voltage: 10.5 V / set • Termination of battery discharge voltage minimum not more than 9.6 V / only to ensure that the battery will not over-discharge.
the relationship between Battery life and temperature curve In the environmental temperature 15 to 25 ℃ and the proper use of circumstances, the use of rechargeable batteries floating design life of 5 to 8 years. Environmental temperature on the battery life is greatly affected when the ambient temperature every 10 ℃ increased battery life of about 50 % reduction. Therefore, to extend battery life, the battery should be maintained as far as possible in 15 to 25 ℃.
Small PV power Intelligent Controller Characteristics： • Solar protection reverse: solar + and - to the anti-polarity, after correct, it can continue to use. 2. Battery Open circuit protection: If the battery breaks, and batteries can be rechargeable normally, the controller will be limited at both ends of load voltage, to ensure that the load is not injury, if at night or solar battery not be chartered, the controller due to its own access to electricity, will not have any action; 3. Overcharge protection: protection of charge voltage higher than the voltage, automatic shutdown of rechargeable batteries. When the voltage then swap to maintain voltage, battery enter Float state, when less than restoring voltage Float closed, are sufficient to enter the state. Have sufficient voltage protection and restoration of both temperature compensation voltage Float; 4. When the battery voltage is lower than the protection of voltage, the controller automatically shut down output in order to protect the battery from damage; 5. Over voltage protection: When high voltage, output shut down automatically to protect against electrical damage. A charge, the release of over-voltage protection are delayed action to prevent the disoperation. 6. With temperature compensation function 7. Variety of control options functions: general charge and discharge mode, light is turned off mode, the opening of the shutdown mode Small PV power Intelligent Controller 5A 、10A
Mid-Power Photovoltaic Controller 1.LCD display: LCD shows Users Display System important information such as the battery voltage, the charge Current and discharge Current, the operation mode and the system parameters, system status by the digital and English 2. Automatic / manual / night features: Programmable Load Control Ways to automatically or manually. Manual, manual load Open or closed. At this time, the evening function invalid. When choosing night function, the controller closed in the daytime load detection evening, Automatically after a period of time delayed opening load, regular time, it has been Dynamic load shut down. Regular time and delay time based programmable Determined; 3. Protection features: over-charged, over-discharged, output overload, over -Pressure, high temperature protection; 4. Float voltage with the temperature compensation function; 5 fast charging functions: the battery voltage falls below a certain value, rapid Start charging automatically, the controller will increase battery power Pressure, when the battery voltage achieve the desired value, started fast charging When Countdown procedures, regular time, with rapid charging state. Therefore, Full use of solar energy. 6. Automatic identification functions: the first power, in accordance with electrical storage controller Pool automatic identification terminal voltage is 12 V or 24 V system; 7. Mode: normal charge-discharge mode, light is turned off mode, - The opening of the shutdown mode. Mid-Power Photovoltaic Controller 20A、30A
High-Power Photovoltaic Controller High-Power Photovoltaic Controller 50A-100A High-Power Photovoltaic Controller 150A-200A Standard 4UCabinets Standard6U Cabinets
High-Power Photovoltaic Controller 250A-400A 100A-200A 1200 StandardCabinets Waterproof Outdoor Mount
The characteristics of the High-Power Photovoltaic Controller (1) • DSP chip microcomputer control, the charge and discharge parameters, temperature compensation coefficient programmable arbitrary , can adapt to the special requirements of different occasions. • LCD dot matrix modules that operate in both English and Chinese menu, users can switch choice; • Various LED indicator to display photovoltaic charge state and load-off state; • 9 touch buttons; • Control circuit totally isolated from the main circuit, high anti-jamming capability; • 1-18 Road solar input control; • Real-time display battery voltage, load current, the total current photovoltaic, Each PV current, battery temperature, the total number of hours photovoltaic power generation, the cumulative load of electricity, and some like several dozen parameters;
The characteristics of the High-Power Photovoltaic Controller (2) • the historical data and Statistics show: the number of charge cycles, the number of discharges, the number of overload, short-circuit number; Programmable voltage generator start-up and shutdown, secondary load-off voltage, wind generator unloading and recovery voltage, street photosensitive parameters such as voltage switch; • Users can set up a rechargeable battery discharge protection and the protection of the load-off state; • With the Second ability to control, that is the main load and secondary load in different battery voltage electrical point of control; • Various charge pressure of a "backlash" control functions, to prevent oscillation switch into the state; • Protection features: with a rechargeable battery, a discharge, output overload, short-circuit, surge, solar or battery against a short circuit to the anti-battery at night and a series of anti-anti-sufficient warning and protection; • RS232/485 interfaces can be allocated to facilitate long-distance remote, remote control; PC control software can be measured real-time data, alarm information, change control parameters, read the daily 30 days maximum battery voltage, battery voltage minimum daily PV and the total volume of electricity consumed by the daily load accumulated historical data; • Parameter settings and the ability to password-protect users may modify password;
The characteristics of the High-Power Photovoltaic Controller (3) • Warning: over-voltage, under-voltage, overload, short-circuit protection, such as alarm; • Multi-channel output report to the police or passive control contact: a rechargeable battery, a battery discharge, Diesel boot control, load disconnect, controller fault; other user-selectable backup alarm contact, such as flood alarm; • Work step by step-ladder pattern of limited mode, PWM mode, the opening of the off-model-turned-down mode, the clock control mode, the light is turned off early-model, which is the model for the first two occasions common load, After four model load occasions against the lights, all the length and timing clock delay can be set up; • Users can also set up parameters including: are charging pressure, Float voltage, voltage absorption launched voltage regulator dynamic coefficient of static coefficient Regulators are filling state time and state absorption time. • Do not brown-out real-time clock function, display and set the clock; • Lightning: According to system requirements, install different levels of mine devices; • A temperature compensation function; • Portfolio ingenious: alone, but also complementary components scenery, inverter control integration models
The characteristics of the inverter ★High reliability for new energy generation power plants are often installed in the mountain and pastoral areas, border, islands, and other traffic inconvenience, if there are large temperature difference between day and night, high-altitude and thin air caused by heat, insulation, as well as facing long transport , once a power failure, repair, the more difficult and therefore the reliability of the power supply to more stringent requirements. ★ High efficiency, the current generation of new energy sources, high cost per unit of electricity, the solar panels is expensive, improving the efficiency of inverter power than improving the efficiency of solar panels more efficient and more economical. ★ Specifically for high altitude, cold zone designed to be at an altitude of 6,000 m and -40 ℃ use of ambient temperature (Note: the need for the use of descending). ★ With the discharge of the battery protection, photovoltaic power plants, wind power is often used for the power station on the battery charge controller, real-time management of discharge, the battery will be over-discharge protection with its own power inverter power supply devices to achieve, not only simplify circuit, reduce costs, but also can avoid the conventional DC motor controller-off arising from the widening arc, thus enhancing the reliability of the system.
On the load configuration • Equipment (or other electrical appliances used) on the plate are generally rated current, voltage data, they are multiplied together to receive VA value corresponding power. Users must use carefully inspect the load power in order to avoid overload. With the general operation of electrical appliances in the state, especially in the standby power than the actual state of the mark on some low power users to be used in the use of electrical appliances and of the nominal power, is starting at the same time consider the impact of current, best left 30 % of the power cushion to ensure reliable power supply; • The load should be considered motor-5 ~ 7 times the cushion to impact current.
protection instruction remarks Output Over-load protection Power load more than 150%, 10 seconds after the shutdown output delay Need to be reset shutdown Short circuit protection If the output short circuit, inverter power will be shut down automatically To protect against the importation Input DC voltage inverter to the anti-polarity, the inverter will be automatically protected Automatically reset, that is, after the failure to eliminate the output will automatically resume Under-voltage Input DC voltage is lower than the under voltage point, inverter power will be shut down automatically Over voltage Input DC voltage is higher than the pressure point, inverter power will be shut down automatically Over heating protection Inverter Power Supply chassis temperature over 75 ℃, the output will be shut down automatically Inverter Power protection
The discharged protection and recovery • Protection of the over-discharged, the battery voltage required to return to work at 226 V or above can start again. Backlash is set up in order to prevent voltage under voltage system in the near oscillations, as shown in Figure 6.1. • Power attention when booting the first time if the battery voltage is in the release point and resume work between power will be in the state and show under voltage shutdown. • Over-discharged protection value and the restoration of working voltage values for the default settings (subject to user requirements set), general without adjustment. If and where adjustments, in the PC board (SNMC) found on the potential for VR2 (Figure 7.3 Position 6), such as lowering the release point, then clockwise adjustment; such as raising the release point, the anti-clockwise adjustment. Potentiometer adjustment semi-circle, the corresponding change in value of the release point about 7 V, for reference purposes only. Picture 6.1
the Maintainability of Photovoltaic power system’s components • Some products photovoltaic power system components can be repaired after used again, known as maintenance parts, but some parts missing validity beyond repair or restoration costs are too high, these components as a non-repair components, the following table lists the photovoltaic power supply Attributes of components in the system.
the Maintainability of Photovoltaic power system’s components Actually in photovoltaic power system , some components can be maintained but some can not be. Such as solar panels, maintenance-free batteries, they are difficult to repair after the failure, which is called as the non-maintenance components, which are directly dealt with a narrow reliability index, the main reliability, failure rate, the average life expectancy of three indicators, reliability, R (t) refers to products (or parts) under the conditions set forth in that time to complete the function of the probability of failure rate λ (t) refers to the moment t work has not yet Failure products, in the moment unit time in the probability of failure; average life expectancy refers to the use of products from the beginning until failure occurred experienced by time. The controller, inverter power supply can be maintained, such as products or components, and its main indicators reliability, failure rate and the average time between failures (MTBF) and mean time to repair faults (MTTR). The components can be maintained and by the maintenance of the components of PV systems, in general, should be understood as products can be maintained.
The designing of the PV Grid-Off system Case： • Requirements: computers, lighting, radar (emotional) of load, time uncertain, the daily power consumption about 200 KWH， batteries to power for three days cloudy. • Battery configuration (in accordance with the allocation of work for three rainy days): Battery groups voltage: 220 V Capacity needs: (daily needed electricity × rainy days × 1000) / (battery voltage ×discharge capacity) Discharge capacity: In the process of battery usage, the battery capacity released by the percentage of its rated capacity, known as the discharge capacity. Discharge capacity to the protection of small batteries, the election is generally recommended 0.5 (200 × 3 × 1000) / (220 * 0.5 * 0.9) = 5754 AH choose 2 V1000AH battery of a total of five groups of 110pcs, a total of 550pcs.
The designing of the PV Grid-Off system • 2. Solar array configurations: Need to configure the maximum power to maintain voltage in the vicinity of 220V , Selection of 85 Wp (or other specifications): open-circuit voltage of 22 V, maximum power point voltage of 17.5, short-circuit current of 545 A. Configured 220/12 = 18pcs connected in series. Each series power is 18 × 85 = 1530Wp. Each series in accordance with the full power operation of 3.2 hours, each providing 3.2 × 1530 = 4896 KWH electricity. Need solar parallel: the daily consumption / (n = array electricity × efficiency) At: 200 / (4.9 * 0.85) = 48 Unit: 0.85 controller for solar and other conductors, such as the efficiency losses. The total need to configure 48 × 18 = 864pcs 85 Wp solar panel
The designing of the PV Grid-Off system • 3. Solar controller configuration According to the trade unions and arrays: configuration 9pcs SD22100 solar controller. Each four-way controller solar arrays. • 4. Inverter configuration Because users do not have to provide the power size of the load, in accordance with the working day to 10 hours to estimate, about 30 KW. Consider cushion and load activated impact of the proposed configuration SN22050KS power inverter. Meanwhile, in order to protect key equipment, such as radar and work normally. Recommends that users load individually configured as the key low-power inverter power, the inverter and battery SN22050KS common DC bus power, the specific size can be agreed with the users. The low-power inverter can be purchased as spared machine.
Grid-connected PV systemRenewable energy grid-connected power generating applications
Grid-connected PV inverter introductionNewest developed 3K、5K、6K、30K、50K，100k，500k Grid-connected Inverter
the comparative advantages and disadvantages of the structure and topology of the common grid-connected inverter • direct inverter system • Low-frequency transformer isolation system
the comparative advantages and disadvantages of the structure and topology of the common grid-connected inverter • the high-frequency isolation system • the high-frequency non- isolation system • Multi- More DC-DC (MPPT), single inverter system
The advantages and disadvantages of direct inverter system Advantages: Eliminates cumbersome Frequency Transformer: high efficiency (96 %), light weight, simple structure. Disadvantages: (1) solar panels and electrical power grids not isolation, solar panels have bipolar voltage power grids, adverse safety. (2) DC type solar panel’s voltage is more than 350 V. This solar components, and even the entire system of higher insulation requirements prone to leakage phenomenon.
The advantages and disadvantages of the Lowe frequency Transformer isolation system Advantages: Using the frequency transformer to change the voltage and isolate the electricity, it has the following advantages: simple structure, high reliability, impact resistance, and good safety performance, MPPT DC voltage 200 V rating in the general-750V. Disadvantages: (1) relatively low system efficiency. (2) heavy
The advantages and disadvantages of high-frequency isolation system Advantages: Having the advantage of electrical isolation as well as light weight, system efficiency 93%. Disadvantages: (1) As isolated DC / AC / DC power hierarchy generally smaller, so this topological structure concentrated in the following 5 KW; (2) high-frequency DC / AC / DC the work of a high frequency, usually dozens KHz, or higher, it is more difficult for EMC system design; (3) the impact of poor system.
The advantages and disadvantages of the high-frequency isolation system Advantages: Same as the first topology structure, eliminating cumbersome frequency transformer, we can bring the following advantages: high efficiency, light weight. At the same time joined the BOOST circuit for DC / DC input voltage DC upgrade, solar array DC input voltage range can be very wide (70 V-750V). Disadvantages: (1) Similarly, the solar panels and electrical power grids not isolation, solar panels have bipolar voltage power grids. (2) The use of high frequency DC / DC, EMC become even more difficult. (3) Lower reliability.
Multi- More DC-DC (MPPT), single inverter system Advantages: • Same as the advantage of the high-frequency isolation system • Due to a number of DC-DC circuit for a number of different tilt array of access, that is, 1 ~ n arrays can have different MPPT voltage, very suitable for photovoltaic building. Disadvantages: • Not with the high-frequency isolation system
Using the low frequency transformer High power three-chase High Power grid-connected Inverter system Using the low frequency transformer High power three-chase High Power grid-connected Inverter system10-500KW
multi-level transformation of the High power three-phase Grid-connected inverter system
The advantages and disadvantages of single machine connecting to the Grid Advantages: • Easy centralized control • Relatively low cost • Easy electromagnetic Compatibility • The better ability of the anti-island effect Disadvantages: • Low reliability, high cost of redundancy to achieve • As all components of PV series-parallel, the relatively low efficiency of power generation • Reduce the relative safety of
The Way Of Distribution of power, multi-branch Grid-connected inverter
the characteristics of way Distribution of power, multi-branch Grid-connected inverter • Each Parallel unit is made up by the dozens of 1.5 KW, 2KW, 2.5KW, 3KW PV Grid-connected inverters parallel. Multiple independent inverter use common DC bus and 220 V AC bus, and then by an independent step-up transformer (220 V/10KV) to the high-voltage power transmission grid. • The program is suitable for application in different photovoltaic arrays tilted surface, or a variety of models of different voltage photovoltaic arrays and networks. Photovoltaic arrays and network inverter can have different specifications. • All the inverter can communicate, remote monitoring and centralized management through CAN bus or RS485 bus or Ethernet connected to the network, and upper control of the PC.
the single-phase grid-connected inverter By, Low-frequency transformer isolation
the single-phase grid-connected inverter By DC boost, high-frequency transformer isolation
The advantages and disadvantages’ distribution of power, multi-branch Grid-connected inverter • Advantages: • Each array independent of each other, and easy to maintain; • Higher reliability of the whole system; • Installation flexibility, adaptability good; • Better safety performance; • Higher utilization of photovoltaic array • Disadvantages: • Relatively high cost • Can be difficult to achieve electromagnetic compatibility • Require careful design and verification of the ability of anti-island effect
The characteristics of grid-connected multi-inverter Parallel • The program calls for installing photovoltaic arrays in the same tilted surface, and requires each sub-array has the same power, voltage and same serial and parallel working model. Multi-inverters operate Parallel connection. • Under the control of the group controllers, inverter "operation tuning ”, not running when not needed, significantly extend the service life of the inverter. N + X can be realized redundancy. • Group controllers provide friendly interface. Users can get the operating parameters, generating capacity, fault enquiries, parameter settings and so on successfully through the LCD screen and key directly.
the advantages and disadvantages of Parallel grid-connected multi-inverter • Advantages: • The whole system reliability; • Installation of a relatively flexible, • Applicability good; • Better safety performance; • High utilization of photovoltaic arrays; • Algorithm flexible, centralized control; • Disadvantages: • Relatively high cost; • Electromagnetic Compatibility difficult to achieve; • Require careful design and verification of the ability of anti-island effect
SG series PV Grid-connected Inverter *Grid-connected PV system includes the PV modules, Grid-connected inverter and network measurement devices and distribution system. *Solar cells can generate DC power electricity *The power is changed to the same- phase, sine wave current through the PV Grid-connected inverter directly and enters into the power grids.
Existing product models and specifications • SG1K5TL 、SG2K5TL （Non-isolated） • SG3K、SG5K、SG6K • SG10K3、SG20K3、SG30K3、SG50K3、SG100K3 • SG200K3、SG500K3
SG Products Characteristics • using U.S.A. TI Company’s 32 DSP microprocessor control • using the fifth generation Intelligent Power Module from Mitsubishi. • maximum power tracking technology (MPPT) • night zero power technology (single-phase) • perfect protection (island effect, over-current, over-temperature, etc.) • stainless steel shell, all enclosed installation（SG3K,SG5K,SG6K） • monitoring capabilities improved, through RS485, Ethernet, and other means of communication