A Spaceborne Digital Payload Power Distribution Architecture

Abstract

The present invention discloses a satellite-borne digital load power distribution architecture, including a pre-voltage regulator module and a current multiplier module cascaded with the pre-voltage regulator module, wherein the current multiplier module corresponds to the digital load one by one. The pre-voltage regulator module is used to convert the bus voltage into a stable output voltage adjustable within a certain range, and the output voltage accuracy reaches ±5%, providing a precise voltage input for the current multiplier module; the current multiplier module adopts a fixed ratio open-loop topology to provide the required input voltage for the satellite-borne digital load. The present invention adopts a miniaturized power distribution architecture with front-stage voltage stabilization and rear-stage fixed ratio voltage reduction, which not only meets the low-voltage and high-current power demand of the new digital load, but also has a higher power distribution efficiency.

Description

Technical Field

[0001] The invention relates to a satellite-borne digital payload power distribution architecture, belonging to the technical field of aerospace power supply and power supply and distribution. Background Art

[0002] In recent years, my country's satellite industry has achieved leapfrog development, with high-throughput communication and navigation satellites being launched and networked continuously. These satellites are increasingly integrated with a large number of digital chips such as microprocessors, memories, and ASICs.

[0003] With the technological advancement of high-speed CPU, DSP, FPGA and other digital chips, their clock frequencies are getting higher and higher, requiring lower power supply voltage (as low as 1V) and higher current (up to tens of amperes) than the previous generation of processors. This puts higher demands on high-throughput communication and navigation satellites that integrate a large number of microprocessors, memories, ASICs and other digital chips. The satellite's power supply and distribution system has the characteristics of miniaturization and can provide low-voltage and high-current power supply for such digital payloads.

[0004] In the traditional satellite platform power distribution architecture, centralized and distributed architectures have been widely used. Patent CN105514979B discloses a satellite power distribution system with high electromagnetic compatibility performance. The system adopts a centralized architecture, with a primary distributor and a DC / DC converter configured by the satellite, and path control is performed at the primary power supply end, and the DC / DC converter is used to achieve centralized conversion and electrical isolation of the primary power supply. The secondary distribution line of this method is relatively long, and large transmission losses will be generated when distributing large currents. Patent CN107140219B discloses a multi-electric aircraft distributed power distribution architecture based on intelligent contactors, in which each power-consuming device of the satellite realizes power conversion and switch control respectively, and the power of the entire satellite is dispersed to multiple busbars, so that multiple distributors and DC / DC converters are responsible for energy control and management in their respective areas. Distributed power distribution realizes voltage stabilization, conversion, and isolation of the power supply voltage by a single module. When low voltage and high current need to be output, the voltage transformation ratio between the front and rear stages is very large, and the conversion efficiency is very low. Summary of the invention

[0005] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and provide a satellite-borne digital load distribution architecture, which has the miniaturized characteristics of a voltage-stabilizing ratio. The high-precision voltage output solves the problem of reduced logic signal noise tolerance caused by lower voltage. The miniaturized design enables the current multiplication module to be deployed closely to the load, reducing the loss caused by long-distance distribution of large currents, meeting the low-voltage and high-current distribution requirements of digital loads, and the distribution power supply based on this architecture maintains a relatively high distribution efficiency.

[0006] The technical solution of the present invention is: a satellite-borne digital load power distribution architecture, including a pre-voltage regulator module, and a current multiplier module cascaded with the pre-voltage regulator module, wherein the current multiplier module corresponds to the digital load one by one; wherein:

[0007] The pre-voltage regulator module is used to convert the bus voltage into a stable output voltage adjustable within a certain range, with an output voltage accuracy of ±5%, providing a precise voltage input for the current multiplier module;

[0008] The current multiplication module adopts a fixed ratio open-loop topology to provide the required input voltage for the satellite-borne digital load.

[0009] Preferably, the current multiplication module adopts a resonant soft switching mode, and the switching frequency operates at the MHz level.

[0010] Preferably, the current multiplication module includes four switch units, a transformer, a synchronous rectifier, and a filter capacitor; wherein the four switch units are recorded as a first switch unit, a second switch unit, a third switch unit and a fourth switch unit, the input end of the first switch unit and the input end of the third switch unit are connected to the positive electrode of the input voltage, the output end of the second switch unit and the output end of the fourth switch unit are connected to the negative electrode of the input voltage, the output end of the first switch unit and the input end of the second switch unit are connected to one end of the primary of the transformer, the output end of the third switch unit and the input end of the fourth switch unit are connected to the other end of the primary of the transformer, the two ends of the secondary of the transformer are respectively connected to the source of the two synchronous rectifiers, the drains of the two synchronous rectifiers are connected to one end of the filter capacitor, and the secondary extraction end of the transformer is connected to the other end of the filter capacitor.

[0011] Preferably, the switching unit is composed of a MOSFET switching tube, a freewheeling diode and a resonant capacitor, the drain of the MOSFET switching tube, the negative electrode of the freewheeling diode and one end of the capacitor are connected in parallel to form the input end of the switching unit, and the source of the MOSFET switching tube, the positive electrode of the freewheeling diode and the other end of the capacitor are connected in parallel to form the output end of the switching unit.

[0012] Preferably, the switch unit is driven in a resonant driving mode, and the driving waveform is a sine wave. By adjusting the filter capacitor and the transformer winding leakage inductance, the resonant frequency of the two is made equal to the switching frequency of the switch unit, and the switching frequency operates at the MHz level.

[0013] Preferably, the pre-regulator module adopts a non-isolated buck-boost DC / DC converter topology, preferably a four-switch Buck-Boost topology, including four switch units using MOSFET switch tubes and a controller. The controller controls the switching state of the four switch units and adjusts the pre-regulator module to output a stable voltage.

[0014] Preferably, through loop feedback control, the output voltage of the current multiplier module is stabilized and accurate, providing a specified input voltage for the connected digital load.

[0015] Preferably, local loop control is adopted to perform self-feedback on the output voltage value of the pre-voltage regulator module to adjust the input voltage of the pre-voltage regulator module.

[0016] Preferably, a voltage adaptive loop control is adopted to feed back the input current value of the current multiplication module to the pre-voltage regulator module to adjust the output voltage of the pre-voltage regulator module.

[0017] Preferably, remote voltage loop control is adopted to feed back the input voltage of the digital load to the pre-regulator module to adjust the input voltage of the digital load to a specified value.

[0018] The beneficial effects of the present invention compared with the prior art are:

[0019] The present invention creatively proposes a satellite-borne power distribution architecture, which adopts a power distribution scheme of front-stage voltage stabilization and rear-stage fixed ratio voltage reduction to meet the effective operation of digital payloads carried by satellites in a space environment. The pre-voltage stabilization module reduces the voltage stabilization requirements of the current multiplier module through pre-voltage stabilization, which is conducive to the current multiplier module adopting a lower cost and simpler structure isolated conversion technology. At the same time, because the pre-voltage stabilization module provides precise voltage input, the current multiplier module can operate with a fixed ratio and operate at a MHz switching frequency using a resonant soft switching method, which is very conducive to the miniaturization of the module. This distribution architecture design not only meets the low-voltage and high-current power demand of digital payloads, but also achieves a higher distribution efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of a satellite-borne digital payload power distribution architecture of the present invention;

[0021] Figure 2 It is a topological structure diagram of the pre-voltage stabilization module of the present invention;

[0022] Figure 3 A topological structure diagram of the current multiplication module of the present invention;

[0023] Figure 4 Schematic diagram of the driving mode of the current multiplier module of the present invention;

[0024] Figure 5 This is a schematic diagram of local loop feedback control adopted in the first embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the adaptive feedback control adopted in the second embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of remote loop feedback control adopted in Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and advantages of the present invention more clear, a satellite-borne digital payload power distribution architecture provided by the present application is further described in detail below in conjunction with the drawings in the specification.

[0028] The primary bus voltage of a typical satellite is usually 24V / 48V / 100V. Some satellites use unregulated or semi-regulated control methods, so the primary bus has a certain fluctuation range, such as 28-37V, 34-42V, etc. However, a single digital payload usually requires a lower voltage such as 1V, 3.3V or 5V. From the typical voltage of the primary bus of the satellite power supply to the voltage requirements of the digital payload of several volts, voltage regulation links such as voltage stabilization, isolation, and voltage transformation are required.

[0029] The voltage-stabilizing ratio power distribution architecture adopted by the present invention divides the voltage regulation process into two stages. Figure 1 The voltage-stabilizing ratio power distribution architecture specifically includes: a pre-voltage stabilizing module 1, and a current multiplying module 2 cascaded with the pre-voltage stabilizing module 1. The two-stage power distribution module is deployed close to the power consumption side, especially the current multiplying module 2 at the rear stage, whose output end is electrically connected to the input end of the digital load power chip within 1mm. The current multiplying module 2 corresponds to the digital load one by one. According to the power size of the digital load, each pre-voltage stabilizing module 1 can cascade 1-4 current multiplying modules 2.

[0030] The pre-regulator module 1, in a non-isolated state, converts the bus voltage into a stable output voltage that is adjustable within a certain range, and provides accurate voltage input for the current multiplier module 2. The pre-regulator module 1 adopts a non-isolated buck-boost DC / DC converter topology to achieve a stable output voltage. The four-switch Buck-Boost topology is preferably used to achieve high-efficiency buck-boost conversion and strong versatility. Figure 2 , including four switch units from the first switch unit 11 to the fourth switch unit 14, a power inductor L1, a filter capacitor C0 and a controller. Among them, the first switch unit and the second switch unit form a first bridge arm, the third switch unit and the fourth switch unit form a second bridge arm, and the controller is used to control the switch states of the four switch units. The specific connection relationship is: the input end of the first switch unit 11 and the output end of the second switch unit 12 are connected to the input end Vi, the output of the first switch unit 11 and the input end of the second switch unit 12 are connected to one end of the inductor L1, the output end of the third switch unit 13 and the input end of the fourth switch unit 14 are connected to the other end of the inductor L1, the input end of the third switch power supply 13 and the output end of the fourth switch unit 14 are respectively connected to the two ends of the filter capacitor C0 and then connected to the output end Vo, and the gate control ends of the first switch unit 11 to the fourth switch unit 14 are respectively connected to the corresponding output ends of the controller.

[0031] In order to meet the requirements of MHz-level switching frequency and module miniaturization, the preferred structure of each switch unit is composed of a MOSFET switch tube, a freewheeling diode and a resonant capacitor, see Figure 2 In the internal structure of the switch unit, the drain of the MOSFET switch tube, the negative electrode of the freewheeling diode and one end of the capacitor are connected in parallel to form the input end of the switch unit, and the source of the MOSFET switch tube, the positive electrode of the freewheeling diode and the other end of the capacitor are connected in parallel to form the output end of the switch unit.

[0032] There are three working modes of the pre-regulator module 1: the first is that when the input voltage Vi is higher than the preset output voltage Vo, the duty cycle of the second bridge arm is set to 1, Q3 is always on, Q4 is always off, and it degenerates into Buck topology zero voltage conversion. After Q1 is turned off, the inductor current flows through the diode of Q2 to achieve zero voltage turn-on of Q2. After the inductor current reverses, Q2 is turned off, L1 and C1 resonate, and Q1 achieves zero voltage turn-on; the second is that when the input voltage Vi is lower than the preset output voltage Vo, the duty cycle of the first bridge arm is set to 1, Q1 is always on, Q2 is always off, and it degenerates into Boost topology zero voltage conversion. After Q4 is turned off, the inductor current flows through the diode of Q3 to achieve zero voltage turn-on of Q3. After the inductor current reverses, Q3 is turned off, L1 and C4 resonate, and Q4 achieves zero voltage turn-on; the third is the synchronous Buck-Boost mode when the input voltage Vi is close to the preset output voltage Vo, Q1 and Q4 share a drive signal and turn on and off together, and the drive signals of Q2 and Q3 are complementary to it, as a synchronous rectifier. During the period when Q2 and Q3 are turned on and Q1 and Q4 are turned off, after the inductor current continues to flow in the reverse direction, Q2 and Q3 are turned off, achieving zero voltage turn-on of Q1 and Q4.

[0033] Assume that the switching period of Q1~Q4 is T. In the first mode, the duty cycle of Q1 is D1, then the output voltage V o =D1·V i In the second mode, the duty cycle of Q4 is D1, and the output voltage V o =V i / (1-D1). In the third mode, the duty cycle of Q1 and Q4 is D1, and the duty cycle of Q2 and Q3 is 1-D1, so the output voltage V o =D1 / (1-D1)·V i .

[0034] The current multiplier module 2 is used to achieve electrical isolation and high-efficiency voltage transformation, converting electrical energy to the voltage level required by the digital load. Due to the application of the pre-voltage regulator module 1, the voltage regulation requirements of the current multiplier module 2 are reduced. The current multiplier module 2 has a low cost and a simple structure. The isolated fixed ratio open-loop conversion circuit uses a resonant soft switching method to achieve operation at a MHz switching frequency, which is very conducive to the miniaturization of the module. The circuit topology of the current multiplier module 2 can be found in Figure 3 , including four switch units from the first switch unit 21 to the fourth switch unit 24, a transformer T1 (transformer T1 winding leakage inductance Lr), synchronous rectifiers Q9, Q10, and a filter capacitor C9. The specific connection relationship is: the input voltage Vi2 is derived from the output voltage Vo of the pre-stabilization module 1, the input end of the first switch unit 21 and the input end of the third switch unit 23 are connected to the positive electrode of Vi2 of the front-stage circuit, the output end of the second switch unit 22 and the output end of the fourth switch unit 24 are connected to the negative electrode of Vi2 of the front-stage circuit, the output end of the first switch unit 21 and the input end of the second switch unit 22 are connected at point A, the output end of the third switch unit and the input end of the fourth switch unit are connected at point B, one end of the transformer T1 winding is connected to point A, and the other end is connected to point B. The two ends of the secondary of the transformer T1 are respectively connected to the source of the synchronous rectifiers Q9 and Q10, the drains of the synchronous rectifiers Q9 and Q10 are connected and then connected to one end of the filter capacitor C9, and the secondary extraction end of the transformer T1 is connected to the other end of the filter capacitor C9.

[0035] To meet the requirements of MHz-level switching frequency and module miniaturization, the preferred structure of each switch unit is composed of a MOSFET switch tube, a freewheeling diode and a resonant capacitor, and the specific connection relationship is the same as the internal connection relationship of the switch unit of the pre-stabilization module 1.

[0036] The switch tube is driven by a resonant drive mode, and the drive waveform is preferably a sine wave, see Figure 4 , Lg and Cgs are the resonant inductor and input capacitor of the switch unit on the current multiplier module 2. The resonant inductor Lg and the switch tube input capacitor Cgs form an LC resonant circuit, so that L and C transfer energy to each other to provide the MOSFET gate drive voltage, control the switch tube to turn on and off, and at the same time, the energy stored in the MOSFET input capacitor Cgs is reused or fed back to the drive power supply, so as to reduce the drive loss and further improve the efficiency of the current multiplier module 2.

[0037] By configuring the values ​​of C5 to C8 and the value of Lr, the resonant frequency is equal to the switching frequency of the switch tube. The current multiplier module 2 operates at this fixed frequency and switches near the current zero crossing point. During the opening and closing process of the drive circuit, the capacitor energy and the series resonant inductor energy can be converted into each other in the form of electric field and magnetic field, which effectively reduces the loss of the drive circuit; at the same time, it greatly reduces the generation of high-order harmonic noise, and only requires a smaller filter at the output voltage. The current multiplier module 2 operates in an open loop, avoiding complex sampling and conditioning circuits and control loop parameter setting processes, and reducing the development cost and cycle of the current multiplier module 2.

[0038] In the solution provided in the first embodiment of the present invention, see Figure 5 The pre-regulator module 1 and the current multiplier module 2 form a local loop control. The pre-regulator module 1 senses its output voltage V F , and feeds back the output voltage collection to the input of its controller. The pre-regulator module 1 adjusts the on and off of the four switches Q1 to Q4 according to the output of the controller, and adjusts its own input voltage to the specified value. Among them, the "specified value" is determined according to the needs of the digital load, specifically the required voltage value of the digital load divided by the voltage conversion coefficient K of the current multiplier module 2. At this time, the voltage obtained by the digital load will show a "droop" characteristic proportional to the output resistance of the current multiplier module 2.

[0039] V o =K·V F -I o R o , K is the voltage conversion coefficient of the current multiplier module 2, I o and R o are the output current and output resistance of current multiplier module 2, V o is the input voltage of the digital load.

[0040] Through theoretical analysis, the power efficiency of a single-stage module power supply is increased by more than 10 times, reaching 40W / cm 3 ; The output voltage range reaches 1V-12V, and the system efficiency of multi-stage conversion is increased to more than 90%. Based on theoretical analysis, multiple experiments were conducted, and the test results verified the feasibility and superiority of the power distribution architecture of the present invention. The specific test data are shown in Table 1. The output voltage accuracy of the front-stage pre-stabilization module is ±5%. The rear-stage current multiplier module has a transformation ratio of 5:1, and the optimal operating point efficiency of the two-stage module cascade is 90.72%. The two-stage modules cooperate to achieve a voltage output of 1V-12V.

[0041] Table 1 Test data of test piece based on the power distribution architecture of Example 1 of the present invention

[0042]

[0043]

[0044] In the solution provided in the second embodiment of the present invention, the pre-regulator module 1 and the current multiplier module 2 form an adaptive loop control, see Figure 6 , a simple, non-isolated feedback connection is established between the pre-regulator module 1 and the current multiplier module 2. The digital load input voltage V o =K·V F ′-I o R o The current multiplier module 2 inputs the current I in Feedback to pre-regulator module 1, pre-regulator module 1 press According to the feedback current, the output voltage V is adjusted F ’, to compensate the output resistance of the current multiplication module 2.

[0045] In the solution provided in the third embodiment of the present invention, the pre-regulator module 1 and the current multiplier module 2 form a remote loop control, see Figure 7 , the input voltage of the digital load is V o The voltage is sensed and fed back to the voltage controller of the pre-regulator module 1. The pre-regulator module 1 adjusts the on and off of the four switches Q1 to Q4 of the pre-regulator module 1 according to the output of the controller, and adjusts the input voltage V of the digital load. o This feedback mechanism provides a more precise and direct output voltage regulation and requires an additional isolation link in the feedback path.

[0046] The above description is only the best specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

[0047] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A satellite-borne digital load power distribution architecture, comprising: A pre-voltage regulator module, and a current multiplier module cascaded with the pre-voltage regulator module, wherein the current multiplier module corresponds to the digital load one by one; wherein, The pre-voltage regulator module is used to convert the bus voltage into a stable output voltage adjustable within a certain range, with an output voltage accuracy of ±5%, providing a precise voltage input for the current multiplier module; The current multiplication module adopts a fixed ratio open-loop topology to provide the required input voltage for the onboard digital load; The current multiplication module adopts a resonant soft switching mode, and the switching frequency operates at the MHz level; The current multiplication module includes four switch units, a transformer, a synchronous rectifier tube, and a filter capacitor; wherein the four switch units are recorded as a first switch unit, a second switch unit, a third switch unit, and a fourth switch unit; the input end of the first switch unit and the input end of the third switch unit are connected to the positive electrode of the input voltage, the output end of the second switch unit and the output end of the fourth switch unit are connected to the negative electrode of the input voltage, the output end of the first switch unit and the input end of the second switch unit are connected to one end of the primary of the transformer, the output end of the third switch unit and the input end of the fourth switch unit are connected to the other end of the primary of the transformer, the two ends of the secondary of the transformer are respectively connected to the source of the two synchronous rectifier tubes, the drains of the two synchronous rectifier tubes are connected to one end of the filter capacitor, and the secondary extraction end of the transformer is connected to the other end of the filter capacitor; The switch unit is composed of a MOSFET switch tube, a freewheeling diode and a resonant capacitor. The drain of the MOSFET switch tube, the negative electrode of the freewheeling diode and one end of the capacitor are connected in parallel to form the input end of the switch unit, and the source of the MOSFET switch tube, the positive electrode of the freewheeling diode and the other end of the capacitor are connected in parallel to form the output end of the switch unit. The switch unit is driven in a resonant manner, and the driving waveform is a sine wave. By adjusting the filter capacitor and the transformer winding leakage inductance, the resonant frequency of the two is made equal to the switching frequency of the switch unit, and the switching frequency operates at the MHz level.

2. The onboard digital load power distribution architecture according to claim 1, characterized in that: The pre-regulator module adopts a non-isolated buck-boost DC / DC converter topology.

3. The onboard digital load power distribution architecture according to claim 2, characterized in that: The pre-regulator module adopts a four-switch Buck-Boost topology, including four switch units using MOSFET switch tubes and a controller. The controller controls the switch states of the four switch units and adjusts the output stable voltage of the pre-regulator module.

4. The onboard digital load power distribution architecture according to claim 1, characterized in that: Through loop feedback control, the output voltage of the current multiplier module is made stable and accurate, providing a specified input voltage for the connected digital load.

5. The onboard digital load power distribution architecture according to claim 4, characterized in that: The local loop control is adopted to conduct self-feedback of the output voltage value of the pre-regulator module to adjust the input voltage of the pre-regulator module.

6. The onboard digital load power distribution architecture according to claim 4, characterized in that: Adopting voltage adaptive loop control, the input current value of the current multiplier module is fed back to the pre-regulator module to adjust the output voltage of the pre-regulator module.

7. The onboard digital load power distribution architecture according to claim 4, characterized in that: Remote voltage loop control is used to feed back the input voltage of the digital load to the pre-regulator module to adjust the input voltage of the digital load to a specified value.

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