An active control circuit for a photovoltaic and thermal power combined power station

Abstract

The utility model provides a kind of active control circuit of photovoltaic and thermal power combined power station, it includes operation mode judging circuit, operating condition judging circuit and tracking deviation flattening circuit.The input end of operation mode judging circuit is connected dispatch system and station monitoring system respectively, and output end connects operating condition judging circuit;Operating condition judging circuit connects tracking deviation flattening circuit.Wherein, operation mode judging circuit is equipped with communication data interface and level conversion chip, and level conversion chip is connected with communication data interface.Operating condition judging circuit is logic judging circuit, and is equipped with integrated circuit and multistage amplifying circuit.Tracking deviation flattening circuit is equipped with connected input stage circuit, intermediate stage circuit, output stage circuit and bias circuit in turn.The utility model structure is simple, low in cost, and has the ability of parsing simple instruction by circuit combination, can realize the demand of automatic regulation station tracking deviation distribution, to improve overall efficiency.

Description

TECHNICAL FIELD

[0001] The utility model relates to new energy technology field, concretely relates to an active control circuit of photovoltaic and thermal power combined power station. BACKGROUND

[0002] Thermal power combined power station is a new type of power station that combines thermal power generation and photovoltaic power generation. Thermal power generation uses fossil fuels such as coal, oil, and natural gas to produce heat energy to drive steam turbines to generate electricity. Photovoltaic power generation uses solar panels to directly convert solar energy into electricity. Thermal power combined power station integrates these two different types of power generation methods to achieve complementary advantages, improve energy utilization efficiency and power supply stability.

[0003] In thermal power combined power station, the thermal power generation part usually serves as the base load to provide stable power output. The photovoltaic power generation part provides additional power during the day when sunlight is abundant, depending on the availability of solar energy. This combination can make full use of the characteristics of different energy sources, reduce dependence on a single energy source, and improve the reliability and flexibility of the power station. The specific advantages are as follows:

[0004] (1) Improve energy utilization efficiency: Although thermal power generation can provide stable power output, its energy conversion efficiency is relatively low, and it produces a large amount of greenhouse gases and pollutants. Photovoltaic power generation is a clean and renewable energy source, but its output power is greatly affected by weather and light conditions. Combining the two can improve the overall energy utilization efficiency to some extent. For example, during the day when sunlight is abundant, photovoltaic power generation can take on part of the load, reducing the output of thermal power generation, thereby reducing fuel consumption and pollutant emissions.

[0005] (2) Enhance power supply stability: Both thermal power generation and photovoltaic power generation have certain limitations. Thermal power generation may be affected by factors such as fuel supply and equipment failure, leading to unstable power supply. Photovoltaic power generation is subject to weather conditions, and its output power will drop significantly on cloudy, dark, or rainy days. By combining thermal and photovoltaic power generation, the output ratio of thermal and photovoltaic power generation can be adjusted flexibly under different weather and load conditions, improving the stability and reliability of power supply.

[0006] (3) Adapt to energy transformation needs: As the world pays more attention to environmental protection and sustainable development, countries are actively promoting energy transformation to reduce dependence on fossil fuels and increase the proportion of renewable energy. Thermal power combined power station, as a transitional energy solution, can gradually introduce photovoltaic power generation based on existing thermal power generation facilities, optimizing and upgrading the energy structure.

[0007] However, there are still many problems in the existing thermal power combined power station, which affect the actual work efficiency and the safety of power grid operation.

[0008] Among them, the main technical problems are also in the tracking deviation allocation aspects of the shortcomings, specifically as follows:

[0009] A, allocation strategy is single: currently many fire light combined power station in tracking deviation allocation strategy is relatively simple, usually just according to the preset fixed proportion of allocation. This way can not fully consider the actual power generation and load demand, leading to unreasonable allocation in some cases, affect the overall performance of the power station. For example, in the sunshine but low load, photovoltaic power generation may produce excess power, and the fire power generation part is still according to the fixed proportion of output, resulting in energy waste.

[0010] B, lack of dynamic adjustment ability: the existing combined power station in tracking deviation allocation often lack of dynamic adjustment ability. Because the output power of photovoltaic power generation changes greatly with weather conditions, and the response speed of fire power generation is relatively slow, so a mechanism is needed to adjust the allocation ratio in real time to adapt to different operating conditions. However, the current power station system lacks the ability in this regard, making it difficult to achieve fast and accurate deviation allocation adjustment.

[0011] C, the impact on system stability is large: unreasonable tracking deviation allocation may have a negative impact on the stability of the power station system. For example, if the allocation is improper, it may cause power imbalance between fire power generation and photovoltaic power generation, causing power grid frequency fluctuation, voltage instability and other problems. In addition, frequent allocation adjustment may also cause a large impact on power station equipment, reducing the service life and reliability of the equipment.

[0012] Although there are intelligent adjustment strategies and supporting systems that apply complex technologies in the prior art, the supporting intelligent system structure is complex and the cost is high. In some local small-scale fire-light linkage stations, the commercial complete system is obviously increased unnecessary cost expenditure, and the system operation follow-up expenditure is also more, which seriously corresponds to the overall yield.

[0013] In summary, it is still necessary to develop a power control circuit with simple structure, low cost, which can adapt to the control scene of fire-light tracking deviation allocation, and realize automatic deviation allocation under the condition of simple instruction. Practical new type content

[0014] The utility model provides a kind of structure simple, cost low, can adapt to the circuit of fire-light integrated power control in view of the problems of prior art.

[0015] To achieve the above object, the technical scheme adopted by the utility model is as follows:

[0016] The utility model provides an active control circuit of photovoltaic and thermal power combined power station, mainly includes operation mode judging circuit, operation state judging circuit and tracking deviation suppression circuit, the input of operation mode judging circuit is connected dispatching system and station monitoring system respectively, and the output is connected operation state judging circuit, operation state judging circuit is connected tracking deviation suppression circuit,

[0017] Operation mode judging circuit is equipped with communication data interface and level conversion chip, and the level conversion chip is connected with communication data interface,

[0018] Operation state judging circuit is logic judging circuit, and is equipped with integrated circuit and multistage amplification circuit,

[0019] Tracking deviation suppression circuit is equipped with input stage circuit, intermediate stage circuit, output stage circuit and bias circuit in proper order.

[0020] Optionally, the integrated circuit includes a three-terminal voltage regulator, an operational amplifier, and a logic gate chip.

[0021] The logic gate chip and the three-terminal voltage regulator are connected to the multistage amplification circuit.

[0022] The operational amplifier is connected to the logic gate chip.

[0023] Optionally, the operation mode judging circuit further comprises a filter circuit.

[0024] The filter circuit is connected to the three-terminal voltage regulator.

[0025] Optionally, the multistage amplification circuit has a double-transistor structure, including an NPN transistor and a PNP transistor.

[0026] The base of the NPN transistor is connected to the collector of the PNP transistor.

[0027] Optionally, the input stage circuit includes a first operational amplifier, and the non-inverting input of the first operational amplifier is connected to a digital-to-analog conversion port.

[0028] The output of the first operational amplifier is connected to the intermediate stage circuit.

[0029] Optionally, the intermediate stage circuit includes a second operational amplifier, and the non-inverting input of the second operational amplifier is connected to the input stage circuit.

[0030] The output of the second operational amplifier is connected to the output stage circuit through a first insulated gate field effect transistor.

[0031] The inverting input of the second operational amplifier is connected to the output stage circuit.

[0032] Optionally, the output stage circuit comprises two operational amplifiers, which are a third operational amplifier and a fourth operational amplifier respectively.

[0033] The non-inverting output terminals of the third and fourth operational amplifiers are connected to the output terminal of the tracking deviation suppression circuit through an H-bridge circuit.

[0034] The output terminals of the third and fourth operational amplifiers are connected to the bias circuit.

[0035] Optionally, the H-bridge circuit is an H-bridge circuit with RC coupling, and the bridge arm midpoint is grounded.

[0036] Optionally, the bias circuit comprises a fifth operational amplifier.

[0037] The non-inverting input terminal of the fifth operational amplifier is connected to the output terminals of the third and fourth operational amplifiers.

[0038] The output terminal of the fifth operational amplifier is connected to the output terminal of the output stage circuit through a second insulated gate field effect transistor.

[0039] Optionally, the inverting input terminal of the fifth operational amplifier is connected to the output terminal of the fifth operational amplifier.

[0040] Compared with the prior art, the utility model has the following beneficial effects:

[0041] The utility model has the advantages of simple structure, low cost, ability of analyzing simple instructions through circuit combination, automatic adjustment of tracking deviation distribution demand of the station, and improved overall efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creative labor under the premise of not paying the creative labor.

[0043] Figure 1 It is a system diagram of the utility model;

[0044] Figure 2 It is a running mode judgment circuit diagram in the specific embodiment of the utility model;

[0045] Figure 3 It is a running state judgment circuit diagram in the specific embodiment of the utility model;

[0046] Figure 4 It is a tracking deviation suppression circuit diagram in the specific embodiment of the utility model. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0048] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0049] In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0050] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0051] It is worth noting that, unless otherwise specified, the methods used in this utility model are all conventional methods; and the raw materials and equipment used are all conventional commercially available products, and their sources are not specifically limited.

[0052] like Figure 1 As shown, this embodiment provides an active power control circuit for a photovoltaic and thermal power combined power plant, which includes an operation mode judgment circuit, an operation status judgment circuit, and a tracking deviation smoothing circuit; the input terminal of the operation mode judgment circuit is connected to the dispatching system and the station monitoring system respectively, and the output terminal is connected to the operation status judgment circuit; the operation status judgment circuit is connected to the tracking deviation smoothing circuit.

[0053] Among them, such as Figure 2As shown, the operation mode determination circuit includes a communication data interface and a level conversion chip, with the level conversion chip connected to the communication data interface. Optionally, in this embodiment, the communication data interface is a DB9 serial communication interface standard. The communication data interface is connected to the dispatching system and the station monitoring system respectively, for receiving dispatching instructions and monitoring signals. Further, in this embodiment, the level conversion chip is selected as the SP3223E chip, and corresponding capacitors C8-C13 and grounding strategies are configured on each pin according to communication requirements. Then, the output terminal of the SP3223E chip is connected to the operation status determination circuit.

[0054] like Figure 3 As shown, the operating status judgment circuit is a logic judgment circuit, and it is equipped with an integrated circuit and a multi-stage amplifier circuit; optionally, the integrated circuit of the operating status judgment circuit includes a three-terminal regulator IC1, an operational amplifier IC3, and a logic gate chip IC2.

[0055] The input terminal of the operating status judgment circuit also includes a filter circuit composed of inductors L1 and L2 and capacitors C1 and C2. A three-terminal voltage regulator IC1's adjustment pin 1 and input pin 2 are connected in parallel on one side of capacitor C2, and a capacitor C3 is connected across the adjustment pin 1 and input pin 2 of the three-terminal voltage regulator IC1. The output pin 3 of the three-terminal voltage regulator IC1 and the output pin 3 of the logic gate chip IC2 are connected to the multi-stage amplifier circuit. The multi-stage amplifier circuit in this embodiment is a dual-transistor structure, including an NPN transistor V1 and a PNP transistor V2. The base of the NPN transistor V1 is connected to the collector of the PNP transistor, and the output pin 3 of the three-terminal voltage regulator IC1 and the output pin 3 of the logic gate chip IC2 are connected to the collector of the PNP transistor V2. A capacitor C4 is connected across the emitter of the dual-transistor structure, and this capacitor is connected to the output terminal U1 of the operating status judgment circuit.

[0056] The logic gate chip IC2 is a dual-input logic gate chip. Its two input pins, 1 and 2, are connected to the operational amplifier IC3 via a resistor network. Specifically, input pin 1 of logic gate chip IC2 is also connected to the output U1 of the operating status determination circuit via resistor R1. A variable resistor RP1 is connected across input pins 1 and 2 of logic gate chip IC2, and then connected to the non-inverting input pin 3 of operational amplifier IC3 via resistor R2. The inverting input pin 1 of operational amplifier IC3 is connected to the output U1 of the operating status determination circuit and input pin 2 and ground pin 4 of logic gate chip IC2 via resistors R4 and R5, respectively.

[0057] The output pin 4 of operational amplifier IC3 is connected to the collector of PNP transistor V2 through resistor R6.

[0058] like Figure 4As shown, the tracking deviation suppression circuit is provided with an input stage circuit, an intermediate stage circuit, an output stage circuit and a bias circuit connected in sequence.

[0059] The input stage circuit comprises a first operational amplifier OP2, and the non-inverting input terminal (+) of the first operational amplifier is connected to the input terminal of the tracking deviation suppression circuit through a resistor R 13 The non-inverting input terminal (-) of the tracking deviation suppression circuit is connected to the inverting input terminal (-) of the first operational amplifier through a resistor R 12 The ground terminal of the tracking deviation suppression circuit is connected to the ground terminal of the first operational amplifier through a resistor R 11 The output terminal of the first operational amplifier is connected to the intermediate stage circuit.

[0060] The intermediate stage circuit comprises a second operational amplifier OP1, and the non-inverting input terminal (+) of the second operational amplifier is connected to the output terminal of the first operational amplifier. The output terminal of the second operational amplifier is connected to the output stage circuit through a first insulated gate field effect transistor, which is selected as MOSFET-N IRF840. The inverting input terminal (-) of the second operational amplifier is connected to the output stage circuit.

[0061] The output stage circuit comprises two operational amplifiers, which are a third operational amplifier OP3 and a fourth operational amplifier OP5. The non-inverting output terminals of the third and fourth operational amplifiers are connected to the positive and negative output terminals +Vout and -Vout of the tracking deviation suppression circuit through an H-bridge circuit. Optionally, the H-bridge circuit is an H-bridge circuit with RC coupling, which comprises capacitors C1 and C2 and resistors R L1 , R L2 , and the midpoints of the bridge arms are grounded. Further, the inverting input terminal (-) of the third operational amplifier is connected to the inverting input terminal (-) of the second operational amplifier, the output terminal of the third operational amplifier and the bias circuit, respectively. The inverting input terminal (-) of the fourth operational amplifier is connected to the inverting input terminal (-) of the second operational amplifier, the output terminal of the fourth operational amplifier and the bias circuit, respectively. The output terminals of the third and fourth operational amplifiers are connected to the bias circuit through resistors R 15 and R 14 , respectively.

[0062] The bias circuit comprises a fifth operational amplifier OP4. Optionally, the non-inverting input terminal (+) of the fifth operational amplifier is connected to the output terminals of the third and fourth operational amplifiers. The inverting input terminal (-) of the fifth operational amplifier is connected to the ground terminal through a resistor R 16 . Further, the inverting input terminal (-) of the fifth operational amplifier is connected to the output terminal of the fifth operational amplifier through a resistor R 17 . The output terminal of the fifth operational amplifier is connected to the output terminal of the output stage circuit through a second insulated gate field effect transistor, which is selected as MOSFET-P IRF940 in the embodiment.

[0063] In the system of the embodiment, the operation mode judging circuit receives the dispatching instruction and the continuous monitoring value, obtains the current combined power plant operation mode through signal conversion, and transmits the information to the operation state judging circuit, and calculates the required instruction increment of each unit. The determination of the instruction value is obtained based on the tracking deviation of the current field station in the tracking deviation suppression circuit. By accurately regulating the active power instruction value of the thermal power unit, the system aims to effectively offset and balance the overall tracking deviation of the thermal and photovoltaic combined power plant.

[0064] The embodiment divides different operation conditions by the thermal and photovoltaic combined operation mode, analyzes the instruction for different conditions, and revises the instruction value according to the preset strategy, thereby improving the control accuracy of the combined power plant of the thermal power unit and the photovoltaic power plant, and making the overall field station better track the dispatching instruction value issued by the local or remote dispatching. Through the real-time compensation of the photovoltaic power plant to the thermal power plant, the climbing pressure of the thermal power unit is reduced, the overall response speed of the field station is improved, and through the real-time compensation of the thermal power unit to the photovoltaic power plant, the tracking deviation caused by the volatility and intermittency of the photovoltaic power plant is reduced by using the thermal power peak regulation stability, and the overall tracking accuracy of the field station is improved.

[0065] Finally, it should be noted that the above content is only used to illustrate the technical scheme of the present application, and is not a limitation on the protection scope of the present application. Simple modifications or equivalent replacements of the technical scheme of the present application made by ordinary skilled in the art do not deviate from the essence and scope of the technical scheme of the present application.

Claims

1. An active control circuit for a photovoltaic and thermal power plant, characterized in that: The application relates to a tracking deviation suppression circuit for a dispatching system and a field station monitoring system, which comprises a running mode judging circuit, a running state judging circuit and the tracking deviation suppression circuit; the input ends of the running mode judging circuit are connected with the dispatching system and the field station monitoring system respectively, and the output end is connected with the running state judging circuit; the running state judging circuit is connected with the tracking deviation suppression circuit; the running mode judging circuit is provided with a communication data interface and a level conversion chip, and the level conversion chip is connected with the communication data interface; the running state judging circuit is a logic judging circuit and is provided with an integrated circuit and a multi-stage amplification circuit; the tracking deviation suppression circuit is sequentially provided with an input stage circuit, an intermediate stage circuit, an output stage circuit and a bias circuit which are connected in sequence. The integrated circuit comprises a three-terminal voltage regulator, an operational amplifier and a logic gate chip; the logic gate chip and the three-terminal voltage regulator are connected with the multi-stage amplification circuit; the operational amplifier is connected with the logic gate chip; the running mode judging circuit is further provided with a filter circuit; the filter circuit is connected with the three-terminal voltage regulator; the multi-stage amplification circuit is a double-transistor structure and comprises an NPN transistor and a PNP transistor; the base of the NPN transistor is connected with the collector of the PNP transistor; the input stage circuit comprises a first operational amplifier, the non-inverting input end of the first operational amplifier is connected with a digital-to-analog conversion port; the output end of the first operational amplifier is connected with the intermediate stage circuit; the intermediate stage circuit comprises a second operational amplifier, the non-inverting input end of the second operational amplifier is connected with the input stage circuit; the output end of the second operational amplifier is connected with the output stage circuit through a first insulated gate field effect tube; the inverting input end of the second operational amplifier is connected with the output stage circuit; the output stage circuit comprises two operational amplifiers, which are a third operational amplifier and a fourth operational amplifier; the non-inverting output ends of the third and fourth operational amplifiers are connected with the output end of the tracking deviation suppression circuit through an H-bridge type circuit; the output ends of the third and fourth operational amplifiers are both connected with the bias circuit; the H-bridge type circuit is an H-type bridge circuit with RC coupling, and the bridge arm midpoint is grounded; the bias circuit comprises a fifth operational amplifier; the non-inverting input end of the fifth operational amplifier is connected with the output ends of the third and fourth operational amplifiers; the output end of the fifth operational amplifier is connected with the output end of the output stage circuit through a second insulated gate field effect tube; the inverting input end of the fifth operational amplifier is connected with the output end of the fifth operational amplifier. ​ ​ 2. The active control circuit for a photovoltaic and thermal power combined power plant according to claim 1, characterized in that: ​ ​ ​ 3. The active control circuit for a photovoltaic and thermal power combined power plant according to claim 2, characterized in that: ​ ​ 4. The active control circuit for a photovoltaic and thermal power combined power plant according to claim 2, characterized in that: ​ ​ 5. The active control circuit for a photovoltaic and thermal power co-located plant according to claim 1, characterized in that: ​ ​ 6. The active control circuit for a photovoltaic and thermal power co-located plant according to claim 5, characterized in that: ​ ​ ​ 7. The active control circuit for a photovoltaic and thermal power co-plant of claim 6, wherein: ​ ​ ​ 8. The active control circuit for a photovoltaic and thermal power co-located plant according to claim 7, characterized in that: ​ 9. The active control circuit for a photovoltaic and thermal power plant according to claim 7 or 8, characterized in that: ​ ​ ​ 10. The active control circuit for a photovoltaic and thermal co-plant according to claim 9, wherein: ​

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