Power supply system with composite function

Abstract

The utility model provides a power supply system with a composite function. The power supply system with the composite function comprises a thermal power generation unit, a photovoltaic power generation unit, a wind power generation unit and an energy storage unit which are all connected with a controller, the energy storage unit comprises a plurality of battery packs connected in series, and a first switch tube and a second switch tube are arranged at the two ends of each battery pack. The first end of the first switch tube is connected with the positive electrode or the negative electrode of the battery pack, the second end of the first switch tube is connected with the first end of the inductor L1, the second end of the inductor L1 is connected with the cathode of the diode D1, the positive electrode of the diode D1 is connected with the second end of the second switch tube, and the first end of the second switch tube is connected with the first end of the first switch tube. The control end of the first switch tube and the control end of the second switch tube are connected with the controller. The stability of the composite power supply system can be improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of power systems, and in particular to a power supply system with composite functions. BACKGROUND

[0002] The power supply system with composite functions integrates multiple power generation methods, such as the combination of traditional energy (thermal power, hydroelectric power) and new energy (solar energy, wind energy, and biomass energy). The power supply system with composite functions can reasonably arrange the power generation plan according to the characteristics of different energy sources and real-time power demand. For example, the system will preferentially dispatch solar photovoltaic power generation equipment to reduce the dependence on high-priced energy (such as oil-fired power generation) if the solar energy resources are abundant and free, thereby reducing the overall energy cost and improving the energy utilization efficiency.

[0003] The energy storage unit plays the role of an "energy buffer" in the power supply system. It stores excess power during the low electricity consumption valley and releases power during the electricity consumption peak or power generation equipment failure. Taking a battery energy storage system as an example, lithium ion battery energy storage can respond to the power change of the system within a few milliseconds, quickly provide or absorb power, stabilize the grid voltage and frequency, and ensure uninterrupted power supply for critical users (such as hospitals, data centers, etc.).

[0004] Due to the differences in battery manufacturing processes, the capacities and internal resistances of individual batteries differ. Overcharging and overdischarging caused by capacity differences can accelerate the aging process of the batteries, thereby affecting the stability of the entire power supply system. CONTENT OF THE INVENTION

[0005] The present disclosure provides a power supply system with composite functions to improve the stability of the composite power supply system.

[0006] The present disclosure provides a power supply system with composite functions, which includes a thermal power generation unit, a photovoltaic power generation unit, a wind power generation unit, and an energy storage unit,

[0007] The energy storage unit includes a plurality of battery packs connected in series. Each battery pack is provided with a first switch tube and a second switch tube at both ends. The first end of the first switch tube is connected to the positive or negative electrode of the battery pack. The second end of the first switch tube is connected to the first end of an inductor L1. The second end of the inductor L1 is connected to the cathode of a diode D1. The anode of the diode D1 is connected to the second end of the second switch tube. The first end of the second switch tube is connected to the first end of the first switch tube,

[0008] The control end of the first switch tube and the control end of the second switch tube are both connected to the controller.

[0009] In an example embodiment of the present disclosure, the power supply system with composite functions further comprises a switch tube driving circuit, the switch tube driving circuit comprising a first multiplexer and a second multiplexer,

[0010] The signal input end of the first multiplexer is connected with the first signal output end of the controller, the gating control end of the first multiplexer is connected with a plurality of second signal output ends of the controller, and the plurality of output ends of the first multiplexer are respectively connected with the control ends of a plurality of first switch tubes.

[0011] The signal input end of the second multiplexer is connected with the third signal output end of the controller, the gating control end of the second multiplexer is connected with a plurality of third signal output ends of the controller, and the plurality of output ends of the second multiplexer are respectively connected with the control ends of a plurality of second switch tubes.

[0012] In an example embodiment of the present disclosure, a first current amplifier U1A and a second current amplifier U2B are sequentially arranged between the first signal output end of the controller and the signal input end of the first multiplexer.

[0013] In an example embodiment of the present disclosure, a third current amplifier U1C and a fourth current amplifier U2D are sequentially arranged between the third signal output end of the controller and the signal input end of the second multiplexer.

[0014] In an example embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0015] A meteorological monitoring unit for monitoring light intensity, wind speed information and wind direction information in real time, the controller being configured to predict the power generation of the photovoltaic power generation unit based on the light intensity, and predict the power generation of the wind power generation unit based on the wind speed information and the wind direction information.

[0016] In an example embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0017] A fault monitoring module for monitoring the output voltage, output current and harmonic content of the power supply system in real time, the output end of the fault monitoring module being connected with the signal input end of the controller.

[0018] In an example embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0019] A reactive power compensation module for compensating the reactive power in the power supply system in real time.

[0020] The power supply system with composite functions provided by the embodiments of the present disclosure has the following working principles and advantages:

[0021] In the embodiments of the present disclosure, by dividing the batteries in the energy storage unit into a plurality of battery groups, a first switch tube and a second switch tube are arranged at both ends (i.e. the positive and negative electrodes) of each battery group, and by controlling the on-off of the first switch tube and the second switch tube, the battery group with high energy is used to charge the inductor L1, and the inductor L1 is used to charge the battery group with low energy, so as to realize the transfer of electric energy from the battery group with high energy to the battery group with low energy, i.e. to realize the equalization charging of the battery group, which can ensure that each battery group can be charged within a suitable voltage and power range, avoid overcharging and overdischarging, thereby prolonging the overall service life of the battery group and improving the stability of the entire composite power supply system. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0023] Figure 1 is a circuit schematic diagram of an energy storage unit provided by the embodiments of the present disclosure;

[0024] Figure 2 is a circuit schematic diagram of a switch tube driving circuit provided by the embodiments of the present disclosure. DETAILED DESCRIPTION

[0025] In order to make the personnel in the technical field better understand the present scheme, the technical solutions in the embodiments of the present scheme will be clearly described below in combination with the drawings in the embodiments of the present scheme. Obviously, the described embodiments are only some of the embodiments of the present scheme, not all. Based on the embodiments in the present scheme, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present scheme.

[0026] The term "comprise" and other any variations thereof in the specification and claims of the present scheme and the above-mentioned drawings means "comprise but not limited to", which is intended to cover non-exclusive inclusion, and is not limited to the examples listed in the text. In addition, the terms "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0027] The implementation of the present disclosure is described in detail below in combination with specific drawings:

[0028] The power supply system with composite function in the present embodiment includes a thermal power generation unit, a photovoltaic power generation unit, a wind power generation unit and an energy storage unit, which are all connected with a controller,

[0029] The energy storage unit comprises a plurality of battery groups connected in series, first switch tubes and second switch tubes are arranged at both ends of each battery group, the first end of the first switch tube is connected with the positive electrode or the negative electrode of the battery group, the second end of the first switch tube is connected with the first end of the inductor L1, the second end of the inductor L1 is connected with the cathode of the diode D1, the anode of the diode D1 is connected with the second end of the second switch tube, the first end of the second switch tube is connected with the first end of the first switch tube,

[0030] The control end of the first switch tube and the control end of the second switch tube are connected with the controller.

[0031] Referring to Figure 1 In the embodiment, the plurality of batteries in the energy storage unit are divided into a plurality of battery groups, and the first switch tube and the second switch tube are arranged at both ends of the battery group to realize the balance control between the battery groups. Taking the battery with the highest energy as the battery group B2 and the battery group with the lowest energy as the battery group B1 as an example, first, the second switch tube Q22 and the first switch tube Q13 are controlled to be turned on, the positive electrode of the battery group B2 charges the inductor L1 through the diode D1 to store the energy in the inductor L1, and the overcharging of the battery group B2 is avoided; then, the second switch tube Q22 and the first switch tube Q13 are controlled to be turned off, and the first switch tube Q11 and the second switch tube Q22 are controlled to be turned on, the energy stored in the inductor L1 is transferred to the battery group B1, and the balance charging of the battery group B1 and the battery group B2 is realized.

[0032] From the above, it can be concluded that, in the embodiment, the batteries in the energy storage unit are divided into a plurality of battery groups, the first switch tube and the second switch tube are arranged at both ends (i.e. the positive electrode and the negative electrode) of each battery group, the on-off of the first switch tube and the second switch tube is controlled, the battery group with high energy is used to charge the inductor L1, and the inductor L1 is used to charge the battery group with low energy, so that the energy is transferred from the battery group with high energy to the battery group with low energy, i.e. the balance charging of the battery groups is realized, it can be ensured that each battery group can be charged in the appropriate voltage and energy range, the overcharging and overdischarging are avoided, the overall service life of the battery group is prolonged, and the stability of the entire composite power supply system is improved.

[0033] In an exemplary embodiment of the present disclosure, the power supply system with a composite function further comprises a switch tube driving circuit, the switch tube driving circuit comprises a first multiplexer and a second multiplexer,

[0034] The signal input end of the first multiplexer is connected with the first signal output end of the controller, the gating control end of the first multiplexer is connected with a plurality of second signal output ends of the controller, and a plurality of output ends of the first multiplexer are respectively connected with the control ends of a plurality of first switch tubes;

[0035] The signal input end of the second multiplex switch is connected with the third signal output end of the controller, the gating control end of the second multiplex switch is connected with the plurality of third signal output ends of the controller, and the plurality of output ends of the second multiplex switch are respectively connected with the control ends of the plurality of second switch tubes.

[0036] Please refer to Figure 2 In the embodiment, the first multiplex switch U2 and the second multiplex switch U3 can be implemented by using multiplex switches CD4051. Considering that the plurality of first switch tubes (Q11, Q12,..., Q18) are turned on at different times, the control signal (i.e. the signal CTRL1 of the first signal output end) of the controller can be connected to the signal input end IO of the first multiplex switch U2. By outputting different gating signals to the first multiplex switch U2, the signal of the signal input end IO can be connected to the corresponding output end.

[0037] For example, when the controller controls the first switch tube Q13 to be turned on, a high-level signal can be output to the signal input end IO of the first multiplex switch U2, and a control signal "010" can be output to the gating control end of the first multiplex switch U2. The gating output end IO2 is in communication with the signal input end IO, and the output end IO2 is connected to the control end of the first switch tube Q13 to control the first switch tube Q13 to be turned on.

[0038] Similarly, considering that the plurality of second switch tubes (Q21, Q21,..., Q28) are turned on at different times, the control signal (i.e. the signal CTRL2 of the third signal output end) of the controller can be connected to the signal input end IO of the second multiplex switch U3. By outputting different gating signals to the second multiplex switch U3, the signal of the signal input end IO can be connected to the corresponding output end.

[0039] For example, when the controller controls the first switch tube Q22 to be turned on, a high-level signal can be output to the signal input end IO of the second multiplex switch U3, and a control signal "001" can be output to the gating control end of the second multiplex switch U3. The gating output end IO1 is in communication with the signal input end IO, and the output end IO1 is connected to the control end of the second switch tube Q22 to control the second switch tube Q22 to be turned on.

[0040] As can be seen from the above, the arrangement of the first multiplex switch U2 and the second multiplex switch U3 in the embodiment can realize the turn-on of the plurality of first switch tubes and the plurality of second switch tubes at different times, which is beneficial to saving the pin resources of the controller.

[0041] In an exemplary embodiment of the present disclosure, the first current amplifier U1A and the second current amplifier U2B are sequentially arranged between the first signal output end of the controller and the signal input end of the first multiplex switch.

[0042] In the embodiment, the first current amplifier U1A and the second current amplifier U2B can be implemented by Darlington tubes ULN2003. The two-stage amplification of the first current amplifier U1A and the second current amplifier U2B can amplify the control signal CTRL1 output by the controller, thereby facilitating the reliable driving of the first switch tube.

[0043] In an exemplary embodiment of the present disclosure, the third signal output end of the controller and the signal input end of the second multi-way switch are sequentially provided with the third current amplifier U1C and the fourth current amplifier U2D.

[0044] In the embodiment, the third current amplifier U1C and the fourth current amplifier U1D can be implemented by Darlington tubes ULN2003. The two-stage amplification of the third current amplifier U1C and the second current amplifier U1D can amplify the control signal CTRL2 output by the controller, thereby facilitating the reliable driving of the second switch tube.

[0045] In an exemplary embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0046] The weather monitoring unit is configured to monitor the light intensity, wind speed information and wind direction information in real time, and the controller is configured to predict the power generation of the photovoltaic power generation unit based on the light intensity, and predict the power generation of the wind power generation unit based on the wind speed information and the wind direction information.

[0047] In the embodiment, the size of the light intensity directly affects the power generation capacity of the photovoltaic power generation unit. The stronger the light intensity, the higher the photovoltaic power generation. At the same time, the wind turbine blades need appropriate wind speed and correct wind direction to effectively capture wind energy and convert it into electrical energy. Therefore, the weather monitoring unit is provided to monitor the light intensity, wind speed information and wind direction information in real time.

[0048] The controller can predict the light intensity based on the light intensity and the pre-stored curve of the photoelectric conversion efficiency varying with the light intensity, thereby predicting the power generation of the photovoltaic power generation unit. The controller can predict the power generation of the wind power generation unit based on the wind speed information and the pre-stored power curve of the wind turbine, and correct the power generation based on the wind direction.

[0049] According to the prediction results of the power generation of the photovoltaic power generation unit and the power generation of the wind power generation unit, the power generation strategy can be planned and adjusted in advance. For example, when it is predicted that the power generation of the photovoltaic power generation unit will increase significantly in the future, the power generation plan of the traditional energy power generation unit (such as thermal power generation or hydroelectric power generation) can be appropriately reduced, and clean energy can be used preferentially to reduce energy cost and carbon emissions.

[0050] From the above, the embodiment can predict the power generation of the photovoltaic power generation unit and the wind power generation unit based on the monitoring data of the meteorological monitoring unit, which can provide a key basis for energy management and scheduling of the entire power supply system.

[0051] In an exemplary embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0052] A fault monitoring module is configured to monitor the output voltage, output current and harmonic content of the power supply system in real time, and the output of the fault monitoring module is connected to the signal input of the controller.

[0053] In this embodiment, through monitoring of voltage and current, damage to power supply system equipment caused by abnormal conditions such as overvoltage and overcurrent can be prevented in a timely manner. For example, when overcurrent is detected, the controller can quickly cut off the faulty circuit or adjust the output of the power generation equipment and energy storage equipment to protect transformers, cables, switches and other equipment from the impact of overload current, prolong the service life of the equipment, and reduce equipment maintenance and replacement costs.

[0054] When the harmonic content is detected to be excessive, the controller can take measures such as starting an active power filter (APF) or a reactive power compensation device (SVC) to filter out harmonics and compensate for reactive power, so as to restore the grid voltage waveform to normal, improve the power factor, and reduce the adverse effects of harmonics on other equipment.

[0055] In an exemplary embodiment of the present disclosure, the power supply system with composite functions further comprises:

[0056] A reactive power compensation module is configured to compensate for reactive power in the power supply system in real time.

[0057] In this embodiment, the reactive power compensation module can accurately determine the demand for reactive power and compensate in a timely manner by monitoring parameters such as voltage, current and power factor of the power supply system. For example, through monitoring of the power factor, if a low power factor is found (indicating a large amount of reactive power), the reactive power compensation module automatically starts the corresponding compensation device for adjustment.

[0058] Therefore, the setting of the reactive power compensation module can improve the power quality of the power supply system and ensure the stability of the power supply system.

[0059] The above embodiments are only used to illustrate the technical solutions of the present disclosure, but not to limit them; although the foregoing embodiments of the present disclosure have been described in detail, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A power supply system with multiple functions, characterized in that, This includes thermal power generation units, photovoltaic power generation units, wind power generation units, and energy storage units, all of which are connected to the controller. The energy storage unit includes multiple battery packs connected in series. Each battery pack has a first switch and a second switch at both ends. The first end of the first switch is connected to the positive or negative terminal of the battery pack, and the second end of the first switch is connected to the first end of an inductor L1. The second end of the inductor L1 is connected to the cathode of a diode D1, and the anode of the diode D1 is connected to the second end of the second switch. The first end of the second switch is connected to the first end of the first switch. The control terminals of the first and second switching transistors are both connected to the controller.

2. A power supply system with multiple functions as described in claim 1, characterized in that, It also includes a switching transistor driving circuit, which comprises a first multiplexer and a second multiplexer. The signal input terminal of the first multiplexer is connected to the first signal output terminal of the controller, the gating control terminal of the first multiplexer is connected to multiple second signal output terminals of the controller, and the multiple output terminals of the first multiplexer are respectively connected to the control terminals of multiple first switching transistors. The signal input terminal of the second multiplexer is connected to the third signal output terminal of the controller, the gating control terminal of the second multiplexer is connected to multiple third signal output terminals of the controller, and the multiple output terminals of the second multiplexer are respectively connected to the control terminals of multiple second switching transistors.

3. A power supply system with multiple functions as described in claim 2, characterized in that, A first current amplifier U1A and a second current amplifier U2B are sequentially arranged between the first signal output terminal of the controller and the signal input terminal of the first multiplexer.

4. A power supply system with multiple functions as described in claim 2, characterized in that, A third current amplifier U1C and a fourth current amplifier U2D are sequentially arranged between the third signal output terminal of the controller and the signal input terminal of the second multiplexer.

5. A power supply system with multiple functions as described in claim 1, characterized in that, Also includes: The meteorological monitoring unit is used to monitor light intensity, wind speed and wind direction information in real time. The controller is used to predict the power generation of the photovoltaic power generation unit based on the light intensity and the power generation of the wind power generation unit based on the wind speed and wind direction information.

6. A power supply system with multiple functions as described in claim 1, characterized in that, Also includes: The fault monitoring module is used to monitor the output voltage, output current and harmonic content of the power supply system in real time. The output terminal of the fault monitoring module is connected to the signal input terminal of the controller.

7. A power supply system with multiple functions as described in claim 1, characterized in that, Also includes: The reactive power compensation module is used to compensate for reactive power in the power supply system in real time.

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