CN203326921U

CN203326921U - Novel-type photovoltaic power optimizer

Info

Publication number: CN203326921U
Application number: CN201320247415XU
Authority: CN
Inventors: 施火泉; 常浩; 王坤; 秦冬雷
Original assignee: Wuxi Hengtong Electric Appliance Co Ltd; Wuxi Intelligent Fast Logical Sensing Network Science And Technology Ltd; Jiangnan University
Current assignee: Wuxi Hengtong Electric Appliance Co Ltd; Wuxi Intelligent Fast Logical Sensing Network Science And Technology Ltd; Jiangnan University
Priority date: 2012-06-14
Filing date: 2013-04-24
Publication date: 2013-12-04
Anticipated expiration: 2023-04-24

Abstract

The utility model proposes a novel-type photovoltaic power optimizer which is directly added to each photovoltaic module and can furthest improve system energy output. The photovoltaic power optimizer firstly acquires voltage and current signals of a photovoltaic module which is connected with the photovoltaic module, and transmits the signals to a central processor in a manner of wired or wireless communication. The interior of the central processor comprises an MPPT algorithm which is carried out for each photovoltaic module. An output voltage of each photovoltaic module and an output current of each photovoltaic module are coordinated according to a strategy of system power optimization at the basis of operation and integration, and direct-current bus voltages of all photovoltaic modules are equal to each other, thereby enabling each photovoltaic module to operate at a best operating point, and enabling the setting of a bus voltage to be more flexible and stable. Therefore, the novel-type photovoltaic power optimizer is better in popularization and application values. The novel-type photovoltaic power optimizer has a more obvious effect especially during series connection mismatch or parallel connection mismatch of the photovoltaic module at a photovoltaic array part or caused by intermittent shielding or aging.

Description

A kind of Novel photovoltaic power optimization device

Technical field

The utility model relates to the photovoltaic generating system applied technical field, is specially a kind of Novel photovoltaic power optimization device.

Background technology

Solar photovoltaic generation system is called for short photovoltaic, it is a kind of photovoltaic effect of utilizing the solar cell semi-conducting material, solar radiation can directly be converted to the electricity generation system of electric energy, in order to obtain higher voltage or electric current output, photovoltaic system is in series or in parallel to form by a plurality of photovoltaic modulies (module).The photovoltaic module array illumination condition that actual large tracts of land is laid is inhomogeneous, and often face more severe phenomenon, as environmental conditions such as shade, fragment, dirts, the imbalance of photovoltaic module output there will be the problem of mismatch when in series or in parallel with each other, and the direct result that mismatch problems causes is exactly the loss of power.

In order to obtain maximum power output, MPPT maximum power point tracking MPPT (maximum power point tracking) is set at present usually in centralized inverter (102) and controls, as shown in Figure 1.Same MPPT is used in the input of inverter multichannel, the difference of each photovoltaic module (100) in None-identified series and parallel branch road, more impossible difference between photovoltaic module is carried out to balance, serious power loss due to appearance series and parallel mismatch, this large solar photovoltaic power plant that is lost in is very general.Therefore the energy loss that centralized control framework causes for the difference of the discreteness of photovoltaic module parameter or solar radiation condition is helpless.

Distributed photovoltaic power optimization control system is that each photovoltaic module connects a photovoltaic power optimizer, and the output of each photovoltaic module is connected on the input point of photovoltaic power optimizer, this distributed photovoltaic power optimizer is followed the tracks of control to each photovoltaic module, but each photovoltaic power optimizer is followed the tracks of alone, can not realize the coordination control of each parallel branch of photovoltaic system, the DC bus-bar voltage that can't guarantee every optical crosstalk photovoltaic assembly equates and stablizes, the lower branch road of voltage can not output current, a reverse current even may circulate, generation for fear of parallel branch circulation, must be at each branch road series diode (101), output current will produce supplementary load loss on this diode.On this basis, more efficiently photovoltaic power optimization system is to have increased a central controller, receive by central controller photovoltaic module voltage, the current data that each photovoltaic power optimizer detects, on computing and comprehensive basis, according to the optimized strategy of system power, coordinate output voltage and the electric current of each photovoltaic module, and the DC bus-bar voltage of every optical crosstalk photovoltaic assembly is equated.Traditionally, require each photovoltaic power optimizer must carry out the MPPT computing, while for some, changing faster external environment, also require each photovoltaic power optimizer to there is arithmetic speed faster, need to select high performance microprocessor, increased the cost of system, also have the computing power consumption.

Summary of the invention

For the problems referred to above, the utility model proposes a kind of Novel photovoltaic power optimization device, this photovoltaic power optimizer directly is additional to each photovoltaic module, can improve to greatest extent the energy output of system.At first photovoltaic power optimizer obtains the voltage and current signal of coupled photovoltaic module, and passes to central controller by wired or wireless communication mode.Central controller is carried out MPPT to each photovoltaic module, on computing and comprehensive basis, according to the optimized strategy of system power, coordinates output voltage and the electric current of each photovoltaic module, and the DC bus-bar voltage of every optical crosstalk photovoltaic assembly is equated.Both can guarantee that each photovoltaic module was operated in best operating point, and can make again bus voltage set more flexibly and more stable, there is popularizing value preferably.Especially photovoltaic array part or intermittent cover or during photovoltaic module series and parallel mismatch that the factor such as aging causes, its effect is more obvious.

Its technical scheme is such: it is characterized in that: it comprises central controller, photovoltaic power optimizer, photovoltaic module, each described photovoltaic module is connected with corresponding described photovoltaic power optimizer, described photovoltaic module output is gone here and there after described photovoltaic power optimizer conversion again, output is connected in parallel, described central controller is inner containing the MPPT algorithm, described photovoltaic power optimizer inside comprises the first telecommunication circuit, described central controller inside also comprises the second communication circuit, described central controller is undertaken by wired or wireless mode is two-way with communicating by letter of described photovoltaic power optimizer, by described the first telecommunication circuit and described second communication circuit, completed.

It is further characterized in that: described photovoltaic power optimizer comprises power circuit, metal-oxide-semiconductor gate drive circuit, DC-DC converter, the first telecommunication circuit, temperature sensing circuit, input terminal voltage/current sampling circuit, output end voltage/current sampling circuit and microprocessor, and described microprocessor connects described the first telecommunication circuit, temperature sensing circuit, input terminal voltage/current sampling circuit, output end voltage/current sampling circuit and metal-oxide-semiconductor gate drive circuit; Described metal-oxide-semiconductor gate drive circuit connects described DC-DC converter.

The beneficial effects of the utility model are, with centralized inverter, with other distributed photovoltaic power optimization devices, compare, the utility model has been introduced central controller, receive the voltage and current that each photovoltaic power optimizer gathers, each photovoltaic module is carried out to maximal power tracing, electric current and voltage according to optimized each photovoltaic module of policy co-ordination of system power, make permutation reach the power output maximum, overcome because discreteness or the influencing each other of solar radiation condition difference of solar module parameter are caused the solar module energy loss, increased the energy output of system.The more outstanding beneficial effect of the utility model is that photovoltaic power optimizer does not need to carry out maximal power tracing, has reduced the computing power consumption, can select the chip that cost is low, and the data of communicating by letter with central controller are simplified more, and overall cost is lower.

The accompanying drawing explanation

Fig. 1 be prior art the photovoltaic generation schematic diagram;

Fig. 2 is enforcement schematic diagram of the present utility model

Fig. 3 is theory of constitution block diagram of the present utility model

Embodiment

As shown in Figure 2, the enforcement schematic diagram of a kind of Novel photovoltaic power optimization device that the utility model patent provides, it comprises photovoltaic module (100), photovoltaic power optimizer (201), central controller (203).Each photovoltaic module (100) photovoltaic power optimizer (201) of connecting, and the output of photovoltaic module (100) connects photovoltaic power optimizer (201), the output of photovoltaic power optimizer (201) is a photovoltaic module optimization string in series (202) mutually.Photovoltaic module optimization string (202) adopts multi-channel parallel then to be connected to inverter (206).Central controller (203) is inner containing the MPPT algorithm.Photovoltaic power optimizer (201) inside comprises the first telecommunication circuit (204), central controller (203) inside also comprises second communication circuit (205), central controller (203) is undertaken by wired or wireless mode is two-way with communicating by letter of photovoltaic power optimizer (201), by the first telecommunication circuit (204) and second communication circuit (205), is completed.

The theory of constitution block diagram of the Novel photovoltaic power optimization device that Fig. 3 provides for the utility model patent, wherein PV+ (301) connects photovoltaic module (100) positive output end, and input sample circuit (303) is sampled and filtering for the output voltage to photovoltaic module (100), electric current; Output sample circuit (309) is sampled and filtering for voltage, electric current to photovoltaic power optimizer output end vo ut+ (308); The output of input sample circuit (303) and output sample circuit (309) is connected to the ADC pin of microprocessor (306); Microprocessor (306) sends the voltage and current data of the photovoltaic module (100) of sampling to central controller (203), central controller (203) is carried out maximal power tracing (MPPT) algorithm, and is transferred to corresponding photovoltaic power optimizer (201) according to the maximum power control parameter that the optimized strategy of system power is calculated each photovoltaic module (100); Microprocessor (306) output pulse signal is to metal-oxide-semiconductor gate drive circuit (305), metal-oxide-semiconductor gate drive circuit (305) output is connected to the gate pole of DC-DC converter (304) metal-oxide-semiconductor, microprocessor (306) is according to the parameter calculated of the central controller (203) received, determine the step-up/down control of DC-DC converter (304), and the duty that changes pwm signal recently regulation output voltage or electric current, control photovoltaic module (100) output and reach maximum power point.The first telecommunication circuit (204) is connected to microprocessor (306), by the first telecommunication circuit (204) and second communication circuit (205), is completed and the communicating by letter of central controller (203).Temperature detecting unit (307) is whether too high and abnormal conditions such as breaking out of fire whether for detection of photovoltaic power optimizer (201) working temperature, during excess Temperature, close photovoltaic power optimizer (201), guarantee the fail safe of system.

Claims

1. a Novel photovoltaic power optimization device, it is characterized in that: it comprises central controller, photovoltaic power optimizer, photovoltaic module, each described photovoltaic module is connected with corresponding described photovoltaic power optimizer, described photovoltaic module output is gone here and there after described photovoltaic power optimizer conversion again, output is connected in parallel, described central controller is inner containing the MPPT algorithm, described photovoltaic power optimizer inside comprises the first telecommunication circuit, described central controller inside also comprises the second communication circuit, described central controller is undertaken by wired or wireless mode is two-way with communicating by letter of described photovoltaic power optimizer, by described the first telecommunication circuit and described second communication circuit, completed.

2. Novel photovoltaic power optimization device according to claim 1, it is characterized in that: described photovoltaic power optimizer comprises power circuit, the metal-oxide-semiconductor gate drive circuit, the DC-DC converter, the first telecommunication circuit, temperature sensing circuit, input terminal voltage/current sampling circuit, output end voltage/current sampling circuit and microprocessor, described microprocessor connects described the first telecommunication circuit, temperature sensing circuit, input terminal voltage/current sampling circuit, output end voltage/current sampling circuit and metal-oxide-semiconductor gate drive circuit, described metal-oxide-semiconductor gate drive circuit connects described DC-DC converter.