A satellite battery module system

Abstract

The present invention relates to a satellite battery module system, which at least includes: a power generation device, which includes a plurality of power generation units that output electric energy for storage by a power supply device or consumption by a system energy consumption device; a power supply device, which is electrically connected to the power generation device, and includes a plurality of secondary battery power supply modules that convert the electric energy output by the power generation device into chemical energy for storage and convert it into electric energy when power is needed. The power generation unit includes a plurality of power generation cells that generate electric energy and a photovoltaic power generation module that outputs electric energy, and the secondary battery power supply module includes a plurality of matched and connected secondary battery boxes and a secondary battery management module, the integrated circuit in the secondary battery management module can be connected to the secondary battery box one by one and regulate the charging and discharging of the secondary battery, and a plurality of secondary batteries in the secondary battery box are connected in series or in parallel in a modular manner, and its energy consumption device is connected to adapt to the internal requirements and external changes of the satellite system.

Description

Technical Field

[0001] The invention relates to the field of satellite power system design, and in particular to a satellite battery module system. Background Art

[0002] Micro-nano satellites have become a research hotspot in the commercial aerospace field due to their low cost and short development cycle, and have received widespread attention worldwide. The capacity of batteries in micro-nano satellites is generally small. According to the existing satellite power supply design, the discharge depth of the battery may exceed 70% after the satellite is separated from the carrier. Such a high discharge depth may cause the satellite to lose power or even be lost. In addition, the satellite may have unstable attitude or abnormal equipment status during in-orbit operation, all of which may cause the battery to be over-discharged and damaged.

[0003] At present, the power supply system of satellites is generally a solar array-battery power supply system. The time it takes for a satellite to orbit the earth is the orbital period. Under normal circumstances, the orbital period includes shadow time and light time. Shadow time refers to the time when the satellite is not exposed to sunlight during the orbital period, and light time refers to the time when the satellite is exposed to sunlight during the orbital period. During the light time, the solar array is illuminated and generates electricity, providing energy for the satellite's electrical equipment and charging the battery pack at the same time; during the shadow time, the battery pack discharges to provide energy for the satellite's electrical equipment. Every time it goes through an orbital cycle, the battery pack undergoes a charge and discharge cycle. As the number of charge and discharge cycles increases, the battery pack's charge retention capacity gradually decreases, that is, after charging to the same charging final voltage, when the same amount of electricity is discharged, the battery pack's discharge final voltage will gradually decrease. In addition, the cycle life of the battery pack is inversely correlated with the discharge depth in each of its charge and discharge cycles. In order to extend its on-orbit service life, it is necessary to limit the discharge depth. When the battery pack is discharging, its charge state at different voltages is related to the temperature. However, when the satellite is in orbit, it can generally ensure that the temperature of the battery pack is within its optimal operating temperature range for a long time. The charging and discharging system during orbit operation is basically constant, so the voltage of the battery pack can characterize the charge state of the battery pack.

[0004] The existing satellite safety protection mode design is relatively simple, with only the power system protection design that can make the satellite enter the minimum power consumption mode and the battery over-discharge protection design that disconnects the battery pack from the power supply bus. Such a design has the following problems: it cannot warn of the discharge terminal voltage drop caused by the normal degradation of the battery pack. When the payload is in normal use, due to the performance degradation of the battery pack, the battery pack voltage is lower than the designed voltage threshold, and the satellite enters the low power consumption mode, affecting the payload's mission execution; it cannot perform hierarchical management for the low battery pack voltage, and different response strategies are given for different voltage values. It is impossible to perform refined and autonomous management of the battery pack voltage that is too low to extend the service life of the battery pack; if the battery pack is over-discharged due to a certain satellite failure, the battery pack is disconnected from the satellite power supply bus, and the satellite is powered off during the shadow time. When this happens, due to the unknown attitude of the satellite, the solar cell array normal may be perpendicular to the sunlight when entering the illumination time, so that it cannot be illuminated and generate electricity, resulting in satellite failure.

[0005] CN106100096B discloses a low-voltage and high-efficiency power supply system for micro-nano satellites, which adopts a 12V low-voltage non-regulated busbar topology, a lithium-ion battery pack as an energy storage mechanism, and a shunt regulation method to achieve power regulation and voltage stabilization and constant current-constant voltage charging for the battery pack. The solar cell arrays are connected in groups, corresponding to direct power supply and shunt power supply respectively; the shunt circuit is designed with fault isolation. When the system determines that the shunt circuit fails, a group of switches that serve as backup for the shunt circuit are used to achieve busbar stabilization and constant voltage charging for the battery pack; the satellite-to-ground power supply interface can realize the satellite power-on and start working when the satellite-rocket is separated; and can perform charging management and over-discharge protection for different life cycles. The power supply system using the present invention has the characteristics of low power consumption, small size, and light weight, and can be applied to micro-nano satellite power supply systems with a load power consumption of 5 to 100W for the entire satellite.

[0006] CN107579587B discloses an energy system suitable for LEO satellites and a control method thereof, comprising a solar cell array, an MPPT circuit unit, a battery pack, a capacitor array, a satellite platform load and a telemetry and remote control unit; wherein the MPPT circuit unit uses three parallel DC-DC conversion modules to track the peak power of the solar cell array in a triple-redundant hot backup mode, and the MPPT circuit unit uses a majority voting control circuit for closed-loop control, and each control circuit generates a drive signal according to the output voltage signal and output current signal of the solar cell array module and the voltage signal and current signal of the battery pack to perform closed-loop control on the corresponding MPPT circuit, so as to achieve maximum power tracking of the solar cell array module and charging management of the battery pack. The solar cell array of the present invention has high utilization rate, high reliability and low system overhead.

[0007] Even so, the battery modules used in satellite systems in the prior art still have at least one or more technical problems:

[0008] 1. The battery modules used in existing satellite systems have complex circuit design and layout when implementing charge and discharge balance and circuit protection control;

[0009] 2. The existing satellite systems are basically customized when designing battery modules and their protection control circuits, that is, a single design is made for each satellite. Therefore, their adaptability and scalability are relatively poor, which will be detrimental to the business development of commercial satellites.

[0010] In addition, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the inventor studied a large number of documents and patents when making the present invention, but due to space limitations, not all details and contents are listed in detail. However, this does not mean that the present invention does not have the characteristics of these prior arts. On the contrary, the present invention already has all the characteristics of the prior art, and the applicant reserves the right to add relevant prior art to the background technology. Summary of the invention

[0011] In view of the deficiencies in the prior art, the present invention provides a satellite battery module system, aiming to solve at least one or more technical problems existing in the prior art.

[0012] To achieve the above-mentioned purpose, the present invention provides a satellite battery module system that can realize balanced current sharing control of secondary batteries, which at least includes: a power generation device, which includes a plurality of power generation units that output electrical energy for storage by a power supply device or consumption by a system energy consumption device; a power supply device, which is electrically connected to the power generation device, and includes a plurality of power supply units that store the electrical energy output by the power generation device and supply it to the energy consumption device for consumption; the power supply unit includes a secondary battery box that cooperates with the power generation cell to convert electrical energy into chemical energy for storage and converts it into electrical energy when power is needed.

[0013] Preferably, the power supply device further comprises a secondary battery management module, which is connected in cooperation with the secondary battery box to form a group of secondary battery power supply modules to cope with internal system requirements and external changes.

[0014] Preferably, the secondary battery management module realizes voltage balancing of the secondary battery box through the following steps:

[0015] A1. Determine a battery voltage deviation value within a safe range based on the power parameters of each single battery in the secondary battery box.

[0016] A2. The secondary battery management module monitors the voltage of all single cells and calculates the average voltage value of all single cells. If the difference between the maximum voltage value and the minimum voltage value reached exceeds the expected single cell voltage deviation value, the secondary battery management module controls the shunt to make the single cell voltage tend to the average voltage.

[0017] Among them, the secondary battery management module will perform voltage balancing management on single cells whose voltage values ​​are higher than the average voltage.

[0018] Preferably, the balanced current management method of the secondary battery management module is divided into an energy consumption shunt method and an energy transfer method. The energy consumption shunt method consumes excess charge during charging, and consumes the energy of the high-voltage or high-charge cells of the single battery in the secondary battery box through a resistor, so as to achieve the purpose of reducing the gap between different single batteries; the energy transfer method redistributes the charge during charging and discharging. If the difference between the maximum voltage value and the minimum voltage value of the single battery exceeds the expected single battery voltage deviation value, the secondary battery management module controls the shunt to transfer energy to the battery with lower voltage, thereby achieving balanced charging and discharging of the secondary battery box.

[0019] Preferably, the balancing time and balancing current required by the secondary battery management module for implementing balancing management are set according to the average time it takes for the single cells in the secondary battery box to fully operate for at least one cycle.

[0020] Preferably, the secondary battery management module stops the balancing control of the secondary battery box when the balancing time arrives, or stops the balancing control of the secondary battery box when the next charging cycle ends and the voltage of the most charged single battery reaches the termination voltage.

[0021] Preferably, the power generation device includes a plurality of power generation cells for generating electric energy and photovoltaic power generation modules for outputting electric energy, and the power generation cells and photovoltaic power generation modules are connected in cooperation to form a group of power generation units, which generate electricity using the photovoltaic principle, and each group of power generation units does not affect each other and can be replaced and used immediately. The power generation cells and photovoltaic power generation modules can be selected into different types according to the needs of the satellite load and cooperate to supply electric energy to the secondary battery power supply module for storage or the energy consumption device for consumption.

[0022] Preferably, the secondary battery management module includes an integrated circuit for controlling the secondary battery box. When the power generation unit outputs electric energy to the secondary battery box for charging, the battery voltage detection unit, battery current detection unit and battery temperature detection unit integrated in the secondary battery management module detect the voltage, current and temperature of the secondary battery box during the charging process, and eliminate the capacity difference between the single cells through balancing control. If it is detected that there is a problem with the voltage, current or temperature of the secondary battery box during the charging process, the power generation unit is promptly cut off from charging the secondary battery box. When the secondary battery box supplies power to an energy consuming device, the battery voltage detection unit, battery current detection unit and battery temperature detection unit integrated in the secondary battery management module detect the voltage, current and temperature of the secondary battery box during the charging process, and eliminate the capacity difference between the single cells through balancing control. If it is detected that there is a problem with the voltage, current or temperature of the secondary battery box during the discharging process, the discharge operation of the secondary battery box to the energy consuming device is promptly cut off.

[0023] Preferably, the secondary battery management module may be provided with a state detection and control protection circuit. The state detection circuit can detect the voltage and / or current value of the secondary battery box and generate relevant signals to be sent to the remote control device. The remote control device can control the connection and power supply relationship between the secondary battery box and the busbar based on the detection signal of the state detection circuit. If the battery is discharged for a long time without taking control measures, when the power of the secondary battery box is close to being discharged, the entire star will be powered off due to insufficient power in just a few minutes, and even a few minutes of over-discharge will still cause irreversible damage to the secondary battery box. The detection circuit integrated in the dedicated battery balancing and current management chip can monitor the discharge of the secondary battery box in real time. Once the possibility of over-discharge is detected, the signal will be transmitted to the remote control device to temporarily shut down some unnecessary loads and / or directly cut off the power supply connection between the secondary battery box and the busbar.

[0024] Preferably, the power generation device includes a plurality of power generation cells for generating electric energy and a photovoltaic power generation module for outputting electric energy, and the power generation cells and the photovoltaic power generation module are connected and form a group of power generation units. Due to comprehensive factors such as launch cost and carrying capacity, in order to obtain solar energy to the maximum extent, the power generation cells need to work at the maximum power point (MPP), and the topological structure of the photovoltaic power generation module should be adopted, which should have the characteristics of high specific power, high efficiency, high stability and high integration. The structure should be as simple as possible, and the function should be based on the perspective of the satellite system to realize the integration of functions such as charging the secondary battery, fully regulating the discharge of the DC bus, and generating peak power at the stable power generation cell working point, so as to reduce the loss of the circuit and improve the specific power of the system.

[0025] Preferably, each group of power generation units and each group of secondary battery power supply modules select different types of power generation cells and secondary battery boxes to cooperate in the process of changes in power demand, environmental changes, and charging and discharging of the secondary battery boxes to ensure smooth operation of the entire system, and the power generation units and secondary battery power supply modules formed based on different types of power generation cells and secondary battery boxes generate the same electric energy to cope with internal system requirements and external changes.

[0026] Preferably, when the satellite system is in the earth's shadow period, based on the power demand of the energy-consuming device, the generator cannot generate electrical energy. The photovoltaic power generation module connected to the generator transmits a signal to the secondary battery box, so that it provides electrical energy to the energy-consuming device for consumption, thereby achieving voltage balance when the secondary battery is discharged; when the satellite system is in the illumination period, the generator converts the absorbed light energy into electrical energy and outputs it to the power supply device for storage or the energy-consuming device for consumption, and the secondary battery box can be charged again during this period.

[0027] Beneficial technical effects of the present invention:

[0028] 1. The secondary battery box in the present invention is manufactured using a printed circuit process and can easily realize modular connection of multiple secondary batteries in series or in parallel. The integrated circuit in the secondary battery management module can be connected to the secondary battery box one by one and regulate the charging and discharging of the secondary battery. Through modular design, the charging and discharging capacity of the secondary battery is further improved, breaking through the previous balanced control of battery charging and discharging.

[0029] 2. In the present invention, each group of power generation units and each group of secondary battery power supply modules cooperate in the process of power demand changes, environmental changes, and charging and discharging of the secondary battery box to ensure the smooth operation of the entire system. The power generation cells and secondary battery boxes can be selected into different types according to the power requirements of the energy-consuming devices, so that the power generation units and secondary battery power supply modules can be replaced at any time to cope with the internal requirements and external changes of the system, thereby facilitating the entire system to make different adjustment strategies according to different situations.

[0030] 3. The integrated circuit compatible with the secondary battery in the secondary battery management module of the present invention can realize functions such as voltage monitoring, current monitoring, and temperature monitoring of each single battery, and eliminate the capacity difference between single batteries through balancing control. The integrated circuit in the secondary battery management module has a simple structure, stable circuit control, and high safety performance, and can better control common problems such as overcharging, over-discharging, overcurrent, and overtemperature of single batteries. The integrated circuit has a simple structure, stable circuit control, and is easy to replace, and simplifies the circuit connection between the secondary battery management module and the secondary battery box.

[0031] 4. In the present invention, the charge state of the secondary battery can be estimated through the secondary battery management module to provide accurate remaining power information for reference, thereby preventing each single cell from being overcharged or over-discharged due to power differences, thereby shortening the battery life or causing the battery to break down. Real-time monitoring of the remaining power information of the single cell will improve the safety and stability of the secondary battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of a preferred structure of the present invention.

[0033] Reference numerals list

[0034] 1: Power generation device 2: Power supply device

[0035] 10: Power generation unit 20: Power supply unit

[0036] 11: Power cell 21: Secondary battery box

[0037] 12: Photovoltaic power generation module 22: Secondary battery management module

[0038] 3: Energy consumption device 20-1: Secondary battery power supply module DETAILED DESCRIPTION

[0039] The following is combined with Figure 1 Provide detailed explanation.

[0040] The present invention relates to a satellite battery module system that can realize balanced current sharing control of secondary batteries to break through the secondary battery management mode of previous satellite systems. The system may include one of the following components: a power generation device 1, including a plurality of power generation units 10 that output electrical energy for storage by a power supply device 2 or consumption by a system energy consumption device 3; a power supply device 2, which is electrically connected to the power generation device 1, including a plurality of power supply units 20 that convert the electrical energy output by the power generation device 1 into chemical energy for storage and convert it into electrical energy when power is needed.

[0041] According to a preferred embodiment, the power supply unit 20 includes a secondary battery power supply module 20-1, the secondary battery power supply module 20-1 includes a secondary battery box 21 that stores energy in the form of chemical energy and outputs it in the form of electrical energy, and a secondary battery management module 22 that controls the voltage balance of the secondary battery. The secondary battery box 21 is manufactured using a printed circuit process and can easily realize modular connection of multiple secondary batteries in series or parallel, and connect them to the energy consumption device 3 formed in series or parallel. The integrated circuit in the secondary battery management module 22 can be connected one-to-one with the secondary battery box 21 and regulate the charging and discharging of the secondary battery.

[0042] According to a preferred embodiment, a plurality of power generating cells 11 for generating electric energy and photovoltaic power generation modules 12 for outputting electric energy are connected in cooperation to form a group of power generation units 10. The power generation units 10 generate electricity using the photovoltaic principle, and each group of power generation units 10 does not affect each other and can be replaced and used immediately. The power generating cells 11 and the photovoltaic power generation modules 12 can be selected into different types according to the needs of the satellite load and cooperate to supply electric energy to the secondary battery power supply module 20-1 for storage or the energy consumption device 3 for consumption.

[0043] According to a preferred embodiment, the power generation cell 11 includes a plurality of cells (11-1, 11-2, ..., 11-N) capable of absorbing light energy, which are modularly connected in parallel or in series. Since the design of the present invention is based on the particularity of satellite production capacity, the cell should adopt a thin-film cell with a smaller structure and better photosensitivity. The cells are connected in series or in parallel using welding strips, and the cell should adopt a configuration that can easily achieve a battery with a larger production capacity.

[0044] According to a preferred embodiment, the type of capacitor array can be selected from one of the following types: electrolytic capacitor, monolithic capacitor, ceramic capacitor, tantalum electrolytic capacitor and polyester capacitor. Preferably, the capacitor array used in this embodiment can be tantalum capacitor. The functions of the capacitor in this embodiment include but are not limited to: filtering, bypassing, decoupling, energy storage and coupling.

[0045] According to a preferred embodiment, the photovoltaic power generation module 12 includes a photovoltaic power generation integrated circuit (12-1, 12-2, ..., 12-N) that outputs electrical energy and can change voltage, and its output end is connected to the secondary battery group 21 or the load end for energy storage or energy consumption. Preferably, the conversion method adopted by the photovoltaic power generation module integrated circuit includes but is not limited to: Superbuck conversion, He-boost conversion and Buck-boost conversion.

[0046] According to a preferred embodiment, the photovoltaic power generation module integrated circuits are connected in series, and each power cell 11 is connected in parallel with the photovoltaic power generation module integrated circuit, wherein the positive input terminal of the photovoltaic power generation module integrated circuit is connected to the positive electrode of the power cell 11, the negative input terminal is connected to the negative electrode of the power cell 11, and the previous photovoltaic power generation module integrated circuit is connected to the negative input terminal of the next photovoltaic power generation module integrated circuit. Preferably, due to comprehensive factors such as launch cost and carrying capacity, the selection of the topological structure of the photovoltaic power generation module should have the characteristics of high specific power, high efficiency, high stability and high integration, and the structure should be as simple as possible. In terms of function, it is necessary to realize the integration of functions such as charging the secondary battery, fully regulating the discharge of the DC bus, and generating peak power at the stable working point of the power cell 11 from the perspective of the satellite system, so as to reduce the loss of the circuit and improve the specific power of the system. The topological structure that can be used includes but is not limited to the series-parallel hybrid photovoltaic power generation module topological structure.

[0047] Preferably, the series-parallel hybrid photovoltaic power generation module topology structure includes a series bus regulator, a charging regulator and a discharging regulator, wherein the bus regulator is used for bus power regulation, and the charging regulator and the discharging regulator are used for charging and discharging management of the secondary battery box 21. This topology structure can maximize the utilization of the power generation capacity of the power generation cell 11, and the bus regulator, charging regulator and discharge regulator are relatively simple in structure and can be designed separately.

[0048] According to a preferred embodiment, the output of the generator 11 is nonlinear, and its PV curve presents a single peak characteristic. In order to obtain solar energy to the maximum extent, the generator 11 needs to operate at the maximum power point (MPP). When the output power of the generator 11 exceeds the power demand of the energy consumption device 3, the bus regulator and the charging regulator work together to make the generator 11 operate near the peak value and maintain the bus voltage stable. The power demand of the energy consumption device 3 determines the electric energy generated by the generator 11, and the remaining electric energy is supplied to the secondary battery box 21 for charging; when the power demand of the energy consumption device 3 exceeds the peak power provided by the generator 11, the generator 11 and the secondary battery box 21 jointly supply power to the load, the bus regulator makes the generator 11 operate at the maximum power point, and the discharge regulator provides insufficient electric energy to power the energy consumption device 3 and maintain the bus voltage constant.

[0049] Preferably, the secondary battery adopts a negative electrode material to form an active material layer formed on the collector layer of the negative electrode for the secondary battery, which includes: Si particles; and a coating material containing Ni and P distributed in an island, dot or network shape in a manner of partially covering the surface of the Si particles. This can not only increase the life of the secondary battery in terms of cycle use, but also facilitate the insertion and removal of the secondary battery electrolyte, and further improve the charge and discharge capacity of the negative electrode for the secondary battery, so as to better provide electrical energy for the energy-consuming device 3.

[0050] According to a preferred embodiment, a shell is disposed outside the secondary battery box 21, a ventilation hole is opened at the bottom of the shell and a dust-proof net is provided on the ventilation hole, so that the secondary battery box 21 can dissipate heat in time during charging and discharging and the dust-proof net can prevent dust from adhering to the secondary battery box 21 and affecting the service life of the secondary battery box 21.

[0051] According to a preferred embodiment, the secondary battery management module 22 includes an integrated circuit for controlling the secondary battery box 21. When the power generation unit 10 outputs electric energy to the secondary battery box 21 for charging, the battery voltage detection unit, battery current detection unit and battery temperature detection unit integrated in the secondary battery management module 22 detect the voltage, current and temperature of the secondary battery box 21 during the charging process, and eliminate the capacity difference between the single cells through balancing control. If it is detected that there is a problem with the voltage, current or temperature of the secondary battery box 21 during the charging process, the power generation unit 10 is promptly cut off from charging the secondary battery box 21. When the secondary battery box 21 supplies power to the energy consumption device 3, the battery voltage detection unit, battery current detection unit and battery temperature detection unit integrated in the secondary battery management module 22 detect the voltage, current and temperature of the secondary battery box 21 during the charging process, and eliminate the capacity difference between the single cells through balancing control. If it is detected that there is a problem with the voltage, current or temperature of the secondary battery box 21 during the discharging process, the discharge operation of the secondary battery box 21 to the energy consumption device 3 is promptly cut off.

[0052] According to a preferred embodiment, a plurality of secondary battery management modules 22 and secondary battery boxes 21 are connected to form a group of secondary battery power supply modules 20-1, and each group of secondary battery power supply modules 20-1 does not affect each other and can be replaced and used immediately. The secondary battery management module 22 and the secondary battery box 21 can select different types according to the needs of the satellite payload and cooperate to supply electric energy to the energy consumption device 3 for consumption. Each group of power generation units 10 and each group of secondary battery power supply modules 20-1 cooperate in the process of power demand changes, environmental changes, and charging and discharging of the secondary battery box 21 to ensure the smooth operation of the entire system. The power generation unit 10 and the secondary battery power supply module 20-1 can be replaced at any time to cope with the internal needs of the system and external changes.

[0053] According to a preferred embodiment, the secondary battery management module 22 controls the overcharge, over-discharge, over-current and other conditions of the single cells in the secondary battery box 21 by performing voltage balancing on the secondary battery box 21. Specifically, the single cells are subjected to large instantaneous currents during the charging and discharging stages, causing some relatively full single cells to directly exceed the damaged voltage range or putting some single cells in a state of deep discharge. If balancing control is not performed, as the charge and discharge cycles increase, the voltages of each single cell gradually diverge, and the service life will be greatly reduced. Therefore, it is necessary to use the secondary battery management module 22 to keep the voltage deviation of the single cell within the expected range. The principle of voltage balancing is that the single cell voltage is compared with the average single cell voltage, and the secondary battery management module 22 controls the single cell voltage that is higher than the average voltage to shunt. Therefore, under the action of the secondary battery management module 22, the voltages of all single cells tend to the average battery voltage.

[0054] According to a preferred embodiment, voltage equalization can be divided into a static equalization stage, a discharge equalization stage, and a charge equalization stage. Specifically, after the secondary battery box 21 completes rapid charging and disconnects the power generation unit 10, the voltage of each single cell begins to drop, and the voltage difference begins to narrow, but the speed of the difference narrowing depends on the consistency difference of the secondary battery box 21. At this time, the secondary battery management module 22 can adjust the speed of voltage difference narrowing. Similarly, after the high-power discharge of the secondary battery box 21 is completed, the voltage of each single cell begins to rebound. The severely attenuated single cell rebounds quickly, and the slightly attenuated or unattenuated single cell rebounds slowly. The difference in rebound speed will cause the voltage difference between the single cells to change in the opposite direction, but the speed of the rebound speed and the change in voltage difference also depend on the consistency difference of the secondary battery box 21. The secondary battery management module 22 can adjust the speed of voltage difference narrowing, and it is in the static equalization stage at this time. The size of the storage capacity of the secondary battery box 21 mainly depends on the consistency health of the single cell, that is, it depends on the capacity of the worst single cell in the secondary battery box 21. The capacity of the worst single cell represents the actual capacity of the secondary battery box 21. The secondary battery management module 22 controls the single cells with good discharge capacity to discharge more to make up for the lack of discharge capacity of the worst battery, so as to make the secondary battery box 21 release as much effective power as possible. The most ideal effect is that the discharge capacity is close to the average capacity of all batteries, and the secondary battery management module 22 adjusts the discharge capacity to make it close to the average capacity during this period, and it is in the discharge balance stage. During charging, the secondary battery management module 22 controls the charging voltage and charging current of the unit battery in real time. When the voltage consistency difference is small, a smaller shunt current can meet the needs. When the voltage consistency difference increases, a larger shunt current is required to meet the needs of the low-capacity battery control voltage. The secondary battery management module 22 adjusts the shunt current and real-time voltage, and it is in the charging balance stage.

[0055] According to a preferred embodiment, since voltage equalization is divided into different stages, the average cell voltage values ​​adapted to the static equalization stage, the discharge equalization stage and the charge equalization stage should be different, that is, the average cell voltage value can correspond to the static average voltage value of the static equalization stage, the discharge average voltage value of the discharge equalization stage and the charge average voltage value of the charge equalization stage, respectively. A cell voltage deviation value within a safe range is predetermined. When the difference between the maximum voltage value and the minimum voltage value reached in each stage exceeds the expected cell voltage deviation value, the secondary battery management module 22 controls the shunt so that the cell voltage tends to the average battery voltage under the action of voltage equalization.

[0056] According to a preferred embodiment, the balanced current management mode of the secondary battery management module 22 is divided into an energy consumption shunting method and an energy transfer method. Specifically, the energy consumption shunting method consumes excess charge during charging, and consumes the energy of the high voltage or high charge cells of the single battery in the secondary battery box 21 through a resistor, so as to achieve the purpose of reducing the gap between different single batteries; the energy transfer method redistributes the charge during charging and discharging. If the difference between the maximum voltage value and the minimum voltage value of the single battery exceeds the expected single battery voltage deviation value, the secondary battery management module 22 controls the shunting to transfer the energy to the battery with lower voltage, thereby achieving balanced charging and discharging of the secondary battery box 21.

[0057] According to a preferred embodiment, the corresponding balancing time and current can be selected according to the average time of one cycle of the single battery in the secondary battery box 21. For example, T b (Balancing time) = (T1 + T2 + T3 + T4) × 75%, where T1 represents the charging time, T2 represents the time for discharging after charging, T3 represents the time for discharging, and T4 represents the time for releasing after discharging. For passive balancing management, the balancing current is generally 0.50A. Preferably, after the balancing time is reached, the balancing control of the secondary battery box 21 will stop. Secondly, if at the end of the next charging cycle, the voltage of the single cell with the most electricity charged reaches the termination voltage, the balancing control of the secondary battery box 21 will also stop. Furthermore, the balancing adjustment of the secondary battery box 21 will be cycled in this way. Preferably, based on this balancing adjustment, at the end of the charging of the single cell, the voltages of all single cells can be equalized to ensure that any single cell can exert its maximum available capacity.

[0058] According to a preferred embodiment, if the power of a single cell reaches saturation after charging (the full power is specified as C=1Ah), after about 10 minutes of relaxation, the current when it is connected to the system energy consumption device is about 1C (a full power of 1Ah is discharged for 1h, and its current is about 1A). After about 10 minutes of relaxation, it is charged with a current of 1C for 70 minutes (considering the constant voltage phase). For the case of charging with a traditional large current (4C), the maximum flowing balanced charge Q=It=4C×10min=0.67Ah. Furthermore, in an embodiment of the present invention, the balancing current is 0.50A. Then the maximum flowing balanced charge Q'=It=0.50A×(10+60+10+70)min=1.25Ah. The balancing method adopted by the present invention has an efficiency of times, while the balancing current is only

[0059] According to a preferred embodiment, when the whole satellite system is running, the secondary battery box 21 continuously supplies power to the system energy consumption device. In order to maintain or extend the service life of the secondary battery box 21, it may be necessary to use a small current for charging and discharging. In this way, while taking into account the service life of the secondary battery box 21, this method will have a higher balancing efficiency. For example, if the power of the single battery reaches saturation after charging (the full power is specified to be C=1Ah), after about 20 minutes of relaxation, the current when it is connected to the system energy consumption device is about 0.25C (the full power 1Ah is discharged for 4h, and its current is about 0.25A). After about 20 minutes of relaxation, it is charged with a current of 0.25C for 250 minutes (considering the constant voltage phase). For the case of charging with a traditional large current (4C), the maximum flow balance charge Q=It=4C×20min=1.33Ah. Further, in an embodiment of the present invention, the balancing current is 0.50A. The maximum flow balance charge Q' = It = 0.50A × (20 + 240 + 20 + 250) min = 4.41Ah. The balancing method adopted by the present invention has an efficiency of times, while the balancing current is only

[0060] Preferably, when using a small current for charging and discharging, the system will generate less heat due to the long balancing time, but still have a high balancing efficiency. Since the satellite operating environment is unsupervised for a long time, the occurrence of problems such as thermal runaway should be avoided as much as possible. Based on this control method, the difficulty or consumption of the system for heat control of the secondary battery box 21 will be greatly reduced, and the risk of thermal runaway is also reduced. Further, in an embodiment of the present invention, at least one secondary battery management module 22 and at least one secondary battery box 21 are connected to form a secondary battery power supply module (20-1) of the power supply device 2. Therefore, based on this modular configuration method combined with the above-mentioned balancing control method, the number of single cells that need to be monitored and managed by any secondary battery management module 22 when performing balancing control on the corresponding secondary battery box 21 is reduced, the difficulty of its control and adjustment and the additional power consumption are reduced, the mutual interference between the single cells is reduced, and the management and adjustment rate and accuracy of any single cell are improved. At the same time, it is also convenient for the system to predict the failure probability of any single cell and make timely adjustments. In addition, the modular design combined with this balancing control method can make different types of configurations for the space architecture of the entire satellite system to meet the requirements of different operating energy consumption devices or power. At the same time, it also enables any secondary battery power supply module (20-1) to exert its maximum available electrical energy to improve its power supply efficiency, thereby maintaining the long-term stable operation of the entire satellite system in space.

[0061] According to a preferred embodiment, the secondary battery management module 22 can estimate the state of charge (SOC) of the secondary battery, that is, calculate the ratio of the remaining battery power to the rated capacity under the same conditions. Accurately estimating the state of charge of the secondary battery can provide accurate remaining power information for reference to prevent the battery from shortening its life or breaking down due to overcharging or over-discharging. The SOC value cannot be measured directly, so it must be indirectly calculated by analyzing and processing the characteristic parameters of the battery or calculating with related algorithms. At present, the commonly used SOC value estimation methods mainly include current integration method, discharge test method, open circuit voltage method, Kalman filter method and neural network method. The current integration method is also called ampere-hour measurement method. Its essence is to estimate the battery SOC by accumulating the amount of electricity charged or discharged when the battery is charged or discharged, and at the same time, the estimated SOC is compensated to a certain extent according to the discharge rate and battery temperature; the discharge test method is to discharge the target battery continuously at a constant current until the cut-off voltage of the battery, and multiply the time used in this discharge process by the value of the discharge current, which is the remaining capacity of the battery; the open circuit voltage method is based on the change relationship between the open circuit voltage (OCV) of the battery and the lithium ion concentration inside the battery, and indirectly fits the one-to-one correspondence between it and the battery SOC. In actual operation, it is necessary to discharge the battery at a fixed discharge rate (generally 1C) after it is fully charged until the discharge stops at the cut-off voltage of the battery, and obtain the relationship curve between OCV and SOC according to the discharge process. When the battery is in actual working state, the current battery SOC can be obtained by looking up the OCV-SOC relationship table according to the voltage value at both ends of the battery; the essence of the Kalman filter method is that it can make the best estimate of the state of a complex dynamic system according to the principle of minimum mean square error. In the Kalman filter method, the nonlinear dynamic system will be linearized into a state space model of the system, and the SOC becomes a state variable inside the model. The established system is a linear discrete system; the neural network method is a new algorithm that simulates the human brain and its neurons to process nonlinear systems. There is no need to deeply study the internal structure of the battery. It only needs to extract a large number of input and output samples that meet its working characteristics from the target battery in advance, and input them into the system established using this method to obtain the SOC value in operation.

[0062] According to a preferred embodiment, the secondary battery management module 22 includes a secondary battery integrated circuit compatible with the secondary battery box 21, which has a simple structure, stable circuit control, easy replacement, and simplifies the circuit connection between the secondary battery management module 22 and the secondary battery box 21.

[0063] Preferably, based on the particularity that the photovoltaic power generation module 12 charges the secondary battery box 21 and the energy consumption device 3 discharges it, the secondary battery management module 22 estimates the charge state of the secondary battery, and controls the charging and discharging of the secondary battery through an integrated circuit compatible with the secondary battery in the secondary battery management module 22, so as to improve the safety and stability of the secondary battery box 21, prevent the secondary battery box 21 from shortening its life or breaking down due to overcharging or over-discharging, and simultaneously achieve voltage balance of the secondary battery box 21.

[0064] Preferably, the integrated circuit adapted to the secondary battery in the secondary battery management module 22 can collect the voltage signal and current signal in the secondary battery box 21 and send low-power or full-power signal data to the secondary battery box 21 based on the collected voltage signal and current signal data. The integrated circuit in the secondary battery management module 22 can divide the voltage, shunt or differentiate the signal data of the secondary battery box 21 based on the low-power or full-power signal data, so that the signal data finally appears in the form of constant current or constant voltage.

[0065] Preferably, the integrated circuit adapted to the secondary battery in the secondary battery management module 22 can charge the secondary battery box 21 in the form of constant current or constant voltage. When the voltage of the secondary battery is low or the charging is slow, the battery may be a faulty battery. The integrated circuit in the secondary battery management module 22 can control the photovoltaic power generation module 12 to charge the secondary battery with a weak current. If the battery becomes hot or the charging is stagnant, the charging can be cut off. When the voltage of the secondary battery is normal, a voltage expectation value is pre-set. The integrated circuit in the secondary battery management module 22 can control the photovoltaic power generation module 12 to charge the secondary battery in the form of constant current. The constant current is based on the value that the secondary battery can withstand, and fast charging is performed. When the voltage rises to the pre-set voltage expectation value, the voltage expectation value is kept unchanged. The integrated circuit in the secondary battery management module 22 controls the photovoltaic power generation module 12 to charge the secondary battery in the form of constant voltage. At the same time, the current change in the constant voltage charging mode can be observed in real time through the integrated circuit adapted to the secondary battery in the secondary battery management module 22 and the current is cut off when the current is too large.

[0066] Furthermore, it is difficult to achieve consistency among the single cells in the secondary battery box 21, and the lifespan of the cells after being used in a group is very short. Thermal runaway is prone to occur, and the characteristics will be different during series and parallel charging and discharging. Therefore, the secondary battery management module 22 needs to regulate the charging and discharging of each single cell in the secondary battery box 21. The integrated circuit in the secondary battery management module 22 that is compatible with the secondary battery can realize functions such as voltage monitoring, current monitoring, and temperature monitoring of each single cell. The integrated circuit in the secondary battery management module 22 has a simple structure, stable circuit control, and high safety performance, and can better control common problems such as overcharging, over-discharging, overcurrent, and overtemperature of single cells.

[0067] Preferably, when the satellite system is in the earth's shadow period, the photovoltaic power generation module 12 controls the output power of the electric energy converted by the power generation cell 11 when it is transmitted to the power supply device 2 based on the collected voltage and / or current value of the bus. The secondary battery management module 22 can detect the total voltage of the secondary battery box 21 and the voltage and / or current value of the single battery therein. Specifically, the output power of the secondary battery box 21 can be controlled by setting the threshold value of the voltage and / or current. When the secondary battery box 21 outputs electric energy to the energy consumption device 3, if the threshold value of the voltage and / or current of the secondary battery box 21 is reached, the power supply of the secondary battery box 21 is cut off to achieve balanced output management of the secondary battery box 21.

[0068] Preferably, when the satellite system is in a long light period, the secondary battery management module 22 controls the input and output voltage and / or current value of the secondary battery box 21, and uses the threshold as a reference to avoid excessive voltage and / or current input to the secondary battery box 21, thereby causing overcharging, overdischarging, etc. of the secondary battery box 21. The secondary battery management module 22 can prevent overcharging, overdischarging, etc. of the secondary battery box 21, thereby facilitating the increase in the service life and / or life of the secondary battery box 21, and further improving the reliability of the satellite system.

[0069] Preferably, if the battery is discharged for a long time without taking control measures, when the power of the secondary battery box 21 is close to being discharged, the entire satellite will be powered off due to insufficient power in just a few minutes, and even a few minutes of over-discharge will still cause irreversible damage to the secondary battery box 21. In order to avoid the operation failure of the entire satellite system caused by the over-discharge of the secondary battery box 21, the integrated circuit adapted to the secondary battery in the secondary battery management module 22 can detect whether the secondary battery box 21 is over-discharged. Once it is detected that the secondary battery box 21 is over-discharged, the secondary battery management module 22 issues an instruction to temporarily shut down some possibly unnecessary loads. If this measure still does not bring obvious results, the connection relationship between the secondary battery box 21 and the busbar can be directly controlled, that is, the way to use the secondary battery box 21 for power supply can be directly cut off. Further, when the satellite system enters the light period and the generator 11 can stably output energy, the secondary battery management module 22 sends a signal to rebuild the connection between the secondary battery box 21 and the busbar. At this time, the generator 11 can continue to charge the secondary battery box 21, and the secondary battery box 21 resumes normal use.

[0070] Preferably, the integrated circuit adapted to the secondary battery in the secondary battery management module 22 used in this embodiment has a strong and wide range of applications, and can be adapted to various types of secondary battery combinations, including but not limited to the specific type and / or quantity of the secondary battery box 21. Furthermore, the entire functional module can be simply expanded according to the needs of satellite applications to provide stronger capabilities, has good scalability, and can meet the diverse needs of today's commercial satellite development.

[0071] The satellite battery module system provided by the present invention has a breakthrough in the previous management mode of aerospace secondary battery boxes 21 in its management of secondary battery boxes 21. Due to the simple circuit, the design and maintenance costs are reduced to a certain extent. In addition, the integrated circuit adapted to the secondary battery in the secondary battery management module 22 used in the battery module system has strong adaptability, can meet the combination requirements of various secondary batteries, and realizes the input and / or output management of balanced current sharing of the battery group.

[0072] It should be noted that the above specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the present invention description and its drawings are illustrative and do not constitute a limitation of the claims. The protection scope of the present invention is defined by the claims and their equivalents.

Claims

1. A satellite battery module system, comprising at least: A power generation device (1) comprises a plurality of power generation units (10) for outputting electric energy for storage by a power supply device (2) or consumption by a system energy consumption device (3), A power supply device (2) is electrically connected to the power generation device (1), and includes a plurality of secondary battery boxes (21) for converting the electrical energy output by the power generation device (1) into chemical energy for storage and converting it into electrical energy when power is needed. It is characterized in that The power supply device (2) further comprises a secondary battery management module (22), wherein the secondary battery management module (22) is connected in cooperation with the secondary battery box (21) to form a group of secondary battery power supply modules (20-1) to cope with internal system requirements and external changes, wherein: The secondary battery management module (22) realizes voltage balancing of the secondary battery box (21) through the following steps: A1. determining a battery voltage deviation value within a safe range according to the power parameters of each single battery in the secondary battery box (21); A2. The secondary battery management module (22) monitors the voltages of all single cells and calculates the average voltage values ​​of all single cells. The average voltage values ​​of the single cells correspond to the static average voltage value in the static balancing stage, the discharge average voltage value in the discharge balancing stage, and the charge average voltage value in the charge balancing stage. If the difference between the maximum voltage value and the minimum voltage value reached by the single cell in each stage exceeds the expected single cell voltage deviation value, the secondary battery management module (22) controls the current diversion so that the voltage of the single cell tends to the average voltage. Each group of the power generation units (10) and each group of the secondary battery power supply modules (20-1) select different types of power generation cells (11) and secondary battery boxes (21) to cooperate in the process of power demand changes, environmental changes, and charging and discharging of the secondary battery box (21) so that the entire system can operate smoothly, and the power generation units (10) and the secondary battery power supply modules (20-1) formed based on different types of power generation cells (11) and secondary battery boxes (21) generate the same electric energy to cope with internal system requirements and external changes.

2. The battery module system according to claim 1, characterized in that: The balanced current management method of the secondary battery management module (22) is divided into an energy consumption split method and an energy transfer method, wherein: The energy consumption shunting method consumes excess charge during charging, and consumes the energy of the high-voltage or high-charge cells of the single cells in the secondary battery box (21) through a resistor, so as to reduce the difference between different single cells; The energy transfer method redistributes the charge during charging and discharging. If the difference between the maximum voltage value and the minimum voltage value of a single cell exceeds the expected single cell voltage deviation value, the secondary battery management module (22) controls the current diversion so that the energy is transferred to the battery with a lower voltage, thereby achieving balanced charging and discharging of the secondary battery box (21).

3. The battery module system according to claim 2, characterized in that: The balancing time and balancing current required when the secondary battery management module (22) implements balancing management are set according to the average time of the single battery in the secondary battery box (21) to fully operate for at least one cycle.

4. The battery module system according to claim 3, characterized in that: The secondary battery management module (22) stops the balancing control of the secondary battery box (21) when the balancing time is reached, or stops the balancing control of the secondary battery box (21) when the next charging cycle ends and the voltage of the single battery with the most electricity charged reaches the termination voltage.

5. The battery module system according to claim 4, characterized in that: The power generation device (1) comprises a plurality of power generation cells (11) for generating electric energy and a photovoltaic power generation module (12) for outputting electric energy, and the power generation cells (11) and the photovoltaic power generation modules (12) are connected in coordination to form a group of power generation units (10).

6. The battery module system according to claim 1, characterized in that: The secondary battery management module (22) can accurately estimate the charge state of the secondary battery based on the particularity that the photovoltaic power generation module (12) charges the secondary battery box (21) and the energy consumption device (3) discharges it, and can control the charging and discharging of the secondary battery through an integrated circuit compatible with the secondary battery in the secondary battery management module (22), and can simultaneously achieve voltage balancing of the secondary battery box (21).

7. The battery module system according to claim 6, characterized in that: The secondary battery management module (22) comprises a state detection circuit and a control protection circuit, wherein: The state detection circuit can be connected to the control protection circuit by detecting the voltage and / or current value of the secondary battery box (21) and sending a signal to the control protection circuit, and the control protection circuit can control the connection and power supply relationship between the secondary battery box (21) and the bus bar based on the detection signal of the state detection circuit.

8. The battery module system according to claim 7, characterized in that: The power generation cell (11) generates electric energy when the satellite system is in an illumination period, and outputs the electric energy to the energy consumption device (3) for consumption or is stored in the power supply device (2) so that the secondary battery box (21) is in a charging state.

9. The battery module system according to claim 8, characterized in that: The power generation cell (11) is unable to generate electric energy when the satellite system is in the earth's shadow period. Based on the power demand of the energy consumption device (3), the photovoltaic power generation module (12) connected to the power generation cell (11) transmits a signal to the secondary battery box (21), so that it provides electric energy to the energy consumption device (3) for consumption, thereby achieving voltage balance when the secondary battery box (21) is discharged.

Images