An ultra-high power space power supply system with enhanced fault tolerance capability

Abstract

The present invention provides an ultra-high power space power supply system with enhanced fault tolerance, including a main power supply, an energy storage device and a high-power power supply controller, wherein the main power supply is a two-dimensional secondary unfolded semi-rigid solar array; the energy storage device is a lithium-ion battery pack and a non-dissipative lithium battery interface management unit, and the high-power power supply controller is used to regulate and control the power supply bus and power. Through the power supply system of the present invention, the load power of the traditional space system of 10kW can be increased to more than 20kW, and the maximum power of the solar array at the end of its life can be more than 30kW. There is no failure mode of losing a solar array, which greatly improves the fault tolerance of the system.

Description

Technical Field

[0001] The present invention relates to a 20kW ultra-high power space power supply system, and in particular to a 20kW ultra-high power space power supply system with enhanced fault tolerance capability. Background Art

[0002] The space power system provides a source of power for the satellite's platform and payload cells. The space power system usually uses a solar array-battery group system. When the satellite is in the illuminated area, the solar array converts light energy into electrical energy, which is then regulated by the sequential switch shunt regulator (S3R) in the power controller to supply power to the satellite, and is charged by the battery charge regulator (BCR) battery group; when the satellite is in the shadow area, the battery group supplies power to the satellite payload through the battery discharge regulator (BDR) in the power controller.

[0003] Traditional space power systems can usually provide 10kW of power for the entire satellite, but cannot meet power requirements above 20kW. In addition, the traditional S3R topology may cause a power loss in a shunt level, and there are single-point links in the BCR and BDR topologies. As the power level of satellites increases, it is necessary to further improve the fault tolerance of the power system, reduce the single point of the energy system, and further improve satellite safety. Summary of the invention

[0004] 1. Technical Problems to be Solved by the Present Invention

[0005] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art, to propose a 20kW ultra-high power space power supply system with enhanced fault tolerance, to improve the power level and reliability of the power supply system, and to enhance the system fault tolerance.

[0006] 2. Technical solution

[0007] The technical solution of the present invention is as follows:

[0008] (1) A 20kW ultra-high power space power system with enhanced fault tolerance capability, the space power system providing a source of power for a platform and payload cells of a satellite during each flight phase of the satellite, the flight phase including an active phase, a period of orbit change and a period of on-orbit; the space power system comprising a high-power power controller, a two-dimensional secondary unfolded semi-rigid solar cell array, a lithium-ion battery pack and a non-dissipative lithium battery interface management unit; the two-dimensional secondary unfolded semi-rigid solar cell array serves as a main power source, the lithium-ion battery pack serves as an energy storage device, the high-power power controller regulates and controls the power supply bus and power, and the non-dissipative lithium battery interface management unit serves as a balancing management device for the lithium-ion battery pack.

[0009] (2) The two-dimensional secondary deployment semi-rigid solar cell array contains 6 string-type semi-rigid substrates, which can achieve a maximum power of more than 30 kW at the end of life. After entering orbit, it is deployed in two dimensions using the connecting frame / inner / middle / outer panels and side panels, and is deployed twice on the transfer orbit and quasi-synchronous orbit.

[0010] (3) The lithium-ion battery pack can be configured as a single group or two groups, using 50Ah high-energy lithium battery cells. The maximum envelope of a single group is 5 in parallel and 20 in series, which can provide a maximum discharge power of 20kW. The series and parallel connection can be configurable and designed according to the satellite load requirements.

[0011] (4) The non-dissipative lithium battery interface management unit adopts non-dissipative balancing technology and a flyback conversion topology to achieve energy transfer between series-connected battery cells and voltage balancing between battery cells.

[0012] (5) The high-power power controller adopts a modular design, and the maximum power configuration is 25.2kW. In order to ensure high reliability of MEA control and consider the symmetry of the structural design, the main error amplifier circuit (MEA) adopts a 4-redundancy design and a 4-out-of-2 voting circuit, as shown in the attached Figure 2 As shown in the figure, the four independent error amplifier channels have their own reference voltage and bus voltage division signal respectively. The output of the four-way error amplifier circuit in hot backup operation is output by a four-out-of-two voting circuit, which first takes the larger output and then the smaller output. The battery charging management circuit (BCM) adopts a three-out-of-two redundancy mode, as shown in the attached figure. Figure 3 As shown in the figure, the three circuits are designed with independent reference voltage and power supply. The outputs of the three error amplifier circuits in hot backup are taken after taking the larger of the two, which improves the fault tolerance of the circuit. The sequential switch shunt regulator (S3R) adopts the redundant mode of switch tube series and diode parallel connection. There is no failure mode of losing a solar array, which improves the fault tolerance of the system. The battery charge regulator (BCR) and battery discharge regulator (BDR) modules adopt single module isolation design to eliminate single points.

[0013] 3. Beneficial effects

[0014] (1) The present invention adopts a space power system solution consisting of a 20kW high-power power controller, a 30kW two-dimensional secondary expansion semi-rigid solar array, a 20kW lithium-ion battery pack and a non-dissipative lithium battery interface management unit, which can increase the load power of the traditional space system from 10kW to more than 20kW and the maximum power of the solar array at the end of its life to more than 30kW.

[0015] (2) The present invention adopts a 4-redundancy design of MEA and a 2-out-of-3 redundancy mode of BCM, a single-module isolation design of multiple parallel redundant battery charge and discharge regulation units (BCDR), and a switch tube series protection mode for S3R. There is no failure mode of losing a solar array, which greatly improves the fault tolerance capability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a power supply system in an embodiment of the present invention;

[0017] Figure 2 Schematic diagram of a MEA two-out-of-four voting circuit in an embodiment of the present invention;

[0018] Figure 3 Schematic diagram of a BCM two-out-of-three voting circuit in an embodiment of the present invention;

[0019] Figure 4 Schematic diagram of a non-dissipative lithium battery interface management unit in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0021] The following will be combined with the accompanying drawings to clearly and completely describe the system solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] like Figure 1 The specific implementation method is now described using a specific example of a 20kW ultra-high power space power supply system.

[0023] (1) A 20kW ultra-high power space power system with enhanced fault tolerance, such as Figure 1 As shown, the space power system provides a source of power for the satellite's platform and payload cells during each flight phase of the satellite, and the flight phase includes the active phase, the orbit change period and the on-orbit period; the space power system includes a 21.6kW high-power power controller, two two-dimensional secondary expansion semi-rigid solar cell arrays, two lithium-ion battery packs and two non-dissipative lithium battery interface management units; the two-dimensional secondary expansion semi-rigid solar cell array serves as the main power source, the lithium-ion battery pack serves as the energy storage device, the high-power power controller regulates and controls the power supply bus and power, and the non-dissipative lithium battery interface management unit serves as a balancing management device for the lithium-ion battery pack.

[0024] (2) The two-dimensional secondary deployment semi-rigid solar cell array contains 6 string-type semi-rigid substrates, which can achieve a maximum power of more than 30 kW at the end of the life span. During the satellite launch phase, the solar cells are folded and pressed against the side wall of the satellite. When the satellite reaches the transfer orbit, part of the pressing and releasing mechanism is unlocked, and the outer panels of the solar cell array are unfolded to 90° and locked, while the remaining 5 solar panels remain folded and pressed. When the satellite reaches the quasi-synchronous orbit, the remaining pressing and releasing mechanism is unlocked, and the remaining connecting frames, inner, middle-inner, and middle-outer solar panels begin to unfold, and the outer solar panels are unlocked and unfolded and locked together with the other solar panels. When locking is about to begin, the side panel release mechanism is triggered, and the upper and lower solar panels begin to unfold until they are finally locked. The entire solar wing is unfolded and locked into a plane with designed rigidity, and a deployment indication signal is given at the same time.

[0025] (3) The lithium-ion battery pack is configured in two groups, using 50Ah high-energy lithium battery cells. Each group of batteries is composed of two modules A and B connected in series. Each module is composed of 5 parallel lithium battery cells in series with 10. The battery cells adopt a 20:19 backup design, that is, when the battery pack is at the end of its life, one battery cell fails in a short circuit, and the maximum discharge depth is 80%, the average output power is not less than 20,800W.

[0026] (4) Figure 4 The non-dissipative lithium battery interface management unit is composed of 6 modules, namely, the central control module (main / standby), the balancing module 1 (main / standby) and the balancing module 2 (main / standby). The central control module realizes 1553B communication with the satellite center computer, outputs internal circuit instructions and collects internal telemetry. The balancing module 1 completes the voltage balancing and battery voltage collection functions of 1 to 10 single cells. The balancing module 2 completes the voltage balancing and battery voltage collection of 11 to 20 single cells. Each balancing unit in the balancing module adopts a bidirectional DC / AC converter lossless balancing circuit, and controls the on and off of the switch tube in the bidirectional DC / AC converter through the balancing excitation pulse sent by the central control module, so that the bidirectional DC / AC converter works in the resonant mode. The transformer output sides of all bidirectional DC / AC converters are interconnected to form a common bus. During the operation of the above balancing circuit, the energy consumption factors on the energy transfer path only include the current limiting resistor and the parasitic resistor, and the energy consumption on both is very small and can be ignored, thus realizing non-dissipative balancing management. The non-dissipative lithium battery interface management unit has completely independent internal main and backup central control circuits, measurement circuits, and balancing circuits, which measure the voltages of 20 single cells and the voltage of the battery pack. The main and backup measurement circuits are completely independent and can be used to determine single cell measurement failures by monitoring the correlation between the single cell voltage and the combined battery voltage, and the combined battery voltage and the voltage of the entire battery group.

[0027] (5) The 21.6kW high-power power supply controller adopts a modular design, and is composed of 25 modules, including 1 capacitor module, 2 telemetry and remote control modules (including MEA and BCM control), 8 shunt regulation modules, and 14 BCDR modules.

[0028] In order to ensure high reliability of MEA control and consider the symmetry of the structural design, the main error amplifier circuit (MEA) adopts a 4-redundancy design and a 4-out-of-2 voting circuit (such as Figure 2 ), the four independent error amplifier channels have their own reference voltage and bus voltage division signal, and the output of the four-way error amplifier circuit in hot standby operation is output after passing through the four-out-of-two voting circuit. Compared with the three-out-of-two voting circuit, the four-out-of-two voting circuit adopted by MEA has further improved the fault tolerance of circuit faults. In addition to the single-way input signal error condition that will not affect the final correct output of the circuit, under some conditions where two-way input signal errors occur, the correctness of the final output of the circuit can still be guaranteed.

[0029] The BCM circuit is used for charging control of the battery pack. Seven BCDRs share one set of BCM circuits. BCM adopts a three-out-of-two redundancy mode (such as Figure 3 ), the three channels are designed with independent reference voltage and power supply respectively. The outputs of the three-channel error amplifier circuit in hot backup are output after passing through a two-out-of-three voting circuit, which can ensure that the final correct output of the circuit will not be affected under the condition of a single-channel input signal error.

[0030] Each shunt regulation module contains three identical S3R circuits. Compared with traditional circuits, the S3R circuit has a switch tube that is connected in series instead of a single one, namely a shunt regulation switch tube and a protection switch tube. When a shunt tube or protection tube fails and causes a certain S3R to be always in the shunt state, the S3R constant shunt protection instruction is sent to shut down the shunt regulation switch tube and the protection switch tube of the S3R, so that it always supplies power to the bus.

[0031] The single-channel BCR and single-channel BDR functions are integrated in the same BCDR module. The single-channel BCDR is designed with filtering and protection circuits at both the bus and battery ends. When a short circuit occurs inside the single-channel BCR or BDR, the current signal is sampled and compared with the set reference voltage to generate a signal to control the protection tube at the bus and battery ends to disconnect, eliminating the single point of the traditional BCDR circuit and improving reliability.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. A person of ordinary skill in the art may make changes, modifications, replacements and modifications to the above embodiments within the scope of the present invention.

Claims

1. An ultra-high power space power supply system with enhanced fault tolerance capability, comprising a main power supply, an energy storage device and a high-power power supply controller, characterized in that: The main power source is a two-dimensional secondary unfolded semi-rigid solar cell array; the energy storage device is a lithium-ion battery pack and a non-dissipative lithium battery interface management unit; wherein the high-power power supply controller is used to regulate and control the power supply bus and power; The energy storage device also includes a non-dissipative lithium battery interface management unit, which is used to perform balanced management on the lithium-ion battery pack; The two-dimensional secondary deployment semi-rigid solar cell array contains 6 string-type semi-rigid substrates, achieving a maximum power of more than 30kW at the end of life. After entering orbit, it is deployed in two dimensions using a connecting frame / inner / middle / outer panels and side panels, and deployed twice on a transfer orbit and a quasi-synchronous orbit. The lithium-ion battery pack is a single group or two groups, each group of which uses a 50Ah high-energy lithium battery as a single unit. The maximum envelope of a single group is 5 parallel and 20 series, which can provide a maximum discharge power of 20kW. The series and parallel connection can be configured and designed according to the satellite load requirements; The high-power power supply controller adopts a modular design, including several SUN modules, several BCDR modules, 1 CAP module and 2 TMTC modules, each module is connected through a 100V bus, wherein each SUN module contains 3 S3R circuits, converting the solar wing electric energy into a 100V bus to power the load, and the S3R circuit adopts a redundant mode of switch tubes in series and diodes in parallel; each BCDR module contains an input switch, an output switch, a BCR circuit and a BDR circuit, the BCR circuit charges the battery by the 100V bus, and the BDR circuit powers the bus load by the battery, the input switch can realize the isolation of the BCR and BDR circuits from the battery, and the output switch can realize the isolation of the BCR and BDR circuits from the bus, thereby ensuring that the BCDR module has no single point link and improving the reliability of the system; the TMTC module contains an MEA circuit, a BCM circuit, a discrete instruction telemetry interface circuit and a 1553B bus interface, wherein the MEA circuit adopts a 4-redundancy design and a 4-out-of-2 voting circuit, and the BCM circuit adopts a 3-out-of-2 redundancy mode, thereby improving the reliability of the control link.

2. The power supply system according to claim 1, characterized in that: The non-dissipative lithium battery interface management unit adopts non-dissipative balancing technology and a flyback conversion topology to achieve energy transfer between series-connected battery cells and voltage balancing between battery cells.

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