# US 11,309,878 B2 · Power conversion system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,878 B2 - Document ID: US11309878B2 - Status: Granted - Kind: B2 - Application number: 17/022,939 - Filed: 2020-09-16 - Published: 2021-03-18 - Granted: 2022-04-19 - Earliest claimed: 2019-09-18 - Assignees: Delta Electronics, Inc. - Applicants: Delta Electronics, Inc. - Inventors: Da Jin; Yahong Xiong; Qinghua Su - Web page: https://patentgrep.com/patent/US11309878B2 ## CPC - H02M 3/1584: {with a plurality of power processing stages connected in parallel} - H03K 17/08: Modifications for protecting switching circuit against overcurrent or overvoltage - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 3/155: using semiconductor devices only - H02M 3/285: {Single converters with a plurality of output stages connected in parallel (parallel operation of a plurality of converters in DC distribution networks H02J1/10)} - H03K 17/08142: {in field-effect transistor switches} - H02M 1/0006: {Arrangements for supplying an adequate voltage to the control circuit of converters} - H02M 1/0054: {Transistor switching losses (periodically suspending operation of switching converter in low power mode H02M1/0035)} - H02M 3/003: {Constructional details, e.g. physical layout, assembly, wiring or busbar connections} - H02M 3/1588: {comprising at least one synchronous rectifier element (H02M3/1582, H02M3/1584 take precedence)} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A power conversion system is provided. The power conversion system includes a power conversion circuit and N clamping circuits. The power conversion circuit includes an input port, an output port, N switching power conversion units and N−1 storage device. The switching power conversion unit includes a first switch and a second switch. N is an integer larger than 1. Two ends of the storage device have a first node and a second node respectively. The clamping circuit includes an absorbing capacitor and an absorbing diode and has a first terminal, a second terminal and a third terminal. The first and second terminals are electrically connected to two ends of the corresponding second switch respectively. The absorbing capacitor and the absorbing diode are serially coupled between the first and second terminals for absorbing a peak voltage. The third terminal is electrically connected to the corresponding first node or the input port. ## Claims ### Claim 1 A power conversion system, comprising: a power conversion circuit, comprising: an input port configured to receive an input voltage; an output port configured to output an output voltage; N cascaded switching power conversion units, wherein each of the N switching power conversion units comprises a first switch and a second switch, the first switch is serially coupled to one terminal of the second switch, the other terminal of the second switch is grounded, the first switch of the first switching power conversion unit is connected to the input port, the first switch of any other of the N switching power conversion units is serially coupled to the first switch of the preceding switching power conversion unit, and N is an integer larger than or equal to 2; and N−1 storage device serially coupled between the input and output ports, wherein two ends of the storage device have a first node and a second node respectively, there are n first switches between the (n)th storage device and the input port, and n is an integer larger than or equal to 1 and smaller than or equal to N−1; and N clamping circuits, wherein each of the N clamping circuits comprises at least one absorbing capacitor and at least one absorbing diode and has a first terminal, a second terminal and a third terminal, the first and second terminals are electrically connected to two ends of the corresponding second switch respectively, the at least one absorbing capacitor and the at least one absorbing diode are serially coupled between the first and second terminals for absorbing a peak voltage generated at the two ends of the corresponding second switch, and the third terminal is electrically connected to the corresponding first node or the input port. ### Claim 2 (depends on 1) The power conversion system according to claim 1, wherein one of the N clamping circuits comprises an absorbing diode, an absorbing capacitor and a discharging diode, a negative electrode of the absorbing diode is electrically connected to one terminal of the absorbing capacitor, a positive electrode of the absorbing diode is electrically connected to one terminal of the corresponding second switch, the other terminal of the absorbing capacitor is electrically connected to the other terminal of the corresponding second switch, a positive electrode of the discharging diode is electrically connected to the negative electrode of the absorbing diode and the absorbing capacitor, and a negative electrode of the discharging diode is electrically connected to the corresponding first node or the input port. ### Claim 3 (depends on 1) The power conversion system according to claim 1, wherein one of the N clamping circuits further comprises a fourth terminal, the third terminal of this clamping circuit is electrically connected to the input port, and the fourth terminal is electrically connected to the first node of the first storage device. ### Claim 4 (depends on 3) The power conversion system according to claim 3, wherein one of the N clamping circuits comprises an absorbing diode and two absorbing capacitors coupled in series, a negative electrode of the absorbing diode is electrically connected to one terminal of the first absorbing capacitor and the input port, a positive electrode of the absorbing diode is electrically connected to one terminal of the second absorbing capacitor and the first node of the first storage device, the other terminal of the first absorbing capacitor is electrically connected to one terminal of the corresponding second switch, and the other terminal of the second absorbing capacitor is electrically connected to the other terminal of the corresponding second switch. ### Claim 5 (depends on 1) The power conversion system according to claim 1, wherein in each of the N switching power conversion units, the first and second switches operate periodically according to a switching period, the first and second switches are turned on and off by complementary signals, and the switching period has a duty ratio. ### Claim 6 (depends on 5) The power conversion system according to claim 5, wherein when the duty ratio is smaller than or equal to 50%, each of the N clamping circuits comprises an absorbing diode, a discharging diode and an absorbing capacitor, the absorbing diode and the discharging diode are connected in series, a positive electrode of the absorbing diode is electrically connected to one terminal of the corresponding second switch, one terminal of the absorbing capacitor is electrically connected to a negative electrode of the absorbing diode and a positive electrode of the discharging diode, the other terminal of the absorbing capacitor is electrically connected to the other terminal of the corresponding second switch, and a negative electrode of the discharging diode is electrically connected to the corresponding first node. ### Claim 7 (depends on 5) The power conversion system according to claim 5, wherein when the duty ratio is larger than or equal to 50%, each of the N clamping circuits comprises an absorbing diode, a discharging diode and an absorbing capacitor, the absorbing diode and the discharging diode are connected in series, a positive electrode of the absorbing diode is electrically connected to one terminal of the corresponding second switch, one terminal of the absorbing capacitor is electrically connected to a negative electrode of the absorbing diode and a positive electrode of the discharging diode, the other terminal of the absorbing capacitor is electrically connected to the other terminal of the corresponding second switch, a negative electrode of the discharging diode of the first clamping circuit is electrically connected to the corresponding first node, and negative electrodes of the discharging diodes of the other clamping circuits are electrically connected to the input port. ### Claim 8 (depends on 5) The power conversion system according to claim 5, further comprising a controller, wherein the controller outputs a set of control signals for controlling the N switching power conversion units, the set of control signals comprises two control signals which are 180 degrees out of phase with respect to each other, one of the two control signal is utilized to control the first switch of the odd-numbered switching power conversion unit, the other control signal is utilized to control the first switch of the even-numbered switching power conversion unit, and the control signals of the first and second switches of each of the N switching power conversion units are complementary to each other. ### Claim 9 A power conversion system, comprising: X power conversion circuits, wherein X is an integer larger than or equal to one, and each of the X power conversion circuits comprises: an input port configured to receive an input voltage; an output port configured to output an output voltage; N cascaded switching power conversion units, wherein each of the N switching power conversion units comprises a first switch and a second switch, the first switch is serially coupled to one terminal of the second switch, the other terminal of the second switch is grounded, the first switch of the first switching power conversion unit is connected to the input port, the first switch of any other of the N switching power conversion units is serially coupled to the first switch of the preceding switching power conversion unit, and N is an integer larger than or equal to 2; and N−1 storage device serially coupled between the input and output ports, wherein two ends of the storage device have a first node and a second node respectively, there are n first switches between the (n)th storage device and the input port, and n is an integer larger than or equal to 1 and smaller than or equal to N−1, wherein the X input ports of the X power conversion circuits are coupled in parallel, and the X output ports of the X power conversion circuits are coupled in parallel; and X clamping circuit assemblies, wherein each of the X clamping circuit assemblies comprises N clamping circuits for absorbing a peak voltage generated at two ends of the second switch of the corresponding power conversion circuit, each of the N clamping circuits comprises at least one absorbing capacitor and at least one absorbing diode and has a first terminal, a second terminal and a third terminal, the first and second terminals are electrically connected to the two ends of the corresponding second switch respectively, the at least one absorbing capacitor and the at least one absorbing diode are serially coupled between the first and second terminals for absorbing the peak voltage generated at the two ends of the corresponding second switch, and the third terminal is electrically connected to the corresponding first node or the input port. ### Claim 10 A power conversion system, comprising: a power conversion circuit, comprising: an input port configured to receive an input voltage; an output port configured to output an output voltage; and N cascaded switching power conversion units, wherein each of the N switching power conversion units comprises a first switch, a second switch and a third switch, one terminal of the first switch of the N switching power conversion units are electrically connected to the input port, wherein in each of the N switching power conversion units, the other terminal of the first switch is electrically connected to one terminal of the second switch and one terminal of the third switch through a storage device, the other terminal of the second switch is electrically connected to the other terminal of the first switch of another switching power conversion unit, the other terminal of the third switch is grounded, N is an integer larger than or equal to 2, and two ends of the storage device have a first node and a second node respectively; and N clamping circuits, wherein each of the N clamping circuits comprises at least one absorbing capacitor and at least one absorbing diode and has a first terminal, a second terminal and a third terminal, the first and second terminals are electrically connected to two ends of the corresponding third switch respectively, the at least one absorbing capacitor and the at least one absorbing diode are serially coupled between the first and second terminals for absorbing a peak voltage generated at the two ends of the corresponding third switch, and the third terminal is electrically connected to the corresponding first node or the input port. ### Claim 11 (depends on 10) The power conversion system according to claim 10, wherein one of the N clamping circuits comprises an absorbing diode, an absorbing capacitor and a discharging diode, a negative electrode of the absorbing diode is electrically connected to one terminal of the absorbing capacitor, a positive electrode of the absorbing diode is electrically connected to one terminal of the corresponding third switch, the other terminal of the absorbing capacitor is electrically connected to the other terminal of the corresponding third switch, a positive electrode of the discharging diode is electrically connected to the negative electrode of the absorbing diode and the absorbing capacitor, and a negative electrode of the discharging diode is electrically connected to the first node of any of the N switching power conversion units. ### Claim 12 (depends on 10) The power conversion system according to claim 10, wherein one of the N clamping circuit further comprises a fourth terminal, the third terminal of this clamping circuit is electrically connected to the input port, and the fourth terminal is electrically connected to the first node of the corresponding switching power conversion unit. ### Claim 13 (depends on 12) The power conversion system according to claim 12, wherein one of the N clamping circuit comprises an absorbing diode and two absorbing capacitors coupled in series, a negative electrode of the absorbing diode is electrically connected to one terminal of the first absorbing capacitor and the input port, a positive electrode of the absorbing diode is electrically connected to one terminal of the second absorbing capacitor and the corresponding first node, the other terminal of the first absorbing capacitor is electrically connected to one terminal of the corresponding third switch, and the other terminal of the second absorbing capacitor is electrically connected to the other terminal of the corresponding third switch. ### Claim 14 (depends on 10) The power conversion system according to claim 10, wherein in each of the N switching power conversion units, the first, second and third switches operate periodically according to a switching period, the first and second switches are turned on and off at the same time, the first and third switches are turned on and off by complementary signals, and the switching period has a duty ratio. ### Claim 15 (depends on 14) The power conversion system according to claim 14, further comprising a controller, wherein the controller outputs a set of control signals for controlling the N switching power conversion unit, the set of control signals comprises N control signals which are 360/N degrees out of phase with respect to each other, the N control signals control the N first switches of the N switching power conversion units respectively, wherein in each of the N switching power conversion units, the control signals of the first and second switches are the same, and the control signal of the third switch is complementary to the control signal of the first switch. ### Claim 16 A power conversion system, comprising: X power conversion circuits, wherein X is an integer larger than or equal to one, and each of the X power conversion circuits comprises: an input port configured to receive an input voltage; an output port configured to output an output voltage; and N cascaded switching power conversion units, wherein each of the N switching power conversion units comprises a first switch, a second switch and a third switch, one terminal of the first switch of the N switching power conversion units are electrically connected to the input port, wherein in each of the switching power conversion units, the other terminal of the first switch is electrically connected to one terminal of the second switch and one terminal of the third switch through a storage device, the other terminal of the second switch is electrically connected to the other terminal of the first switch of another switching power conversion unit, the other terminal of the third switch is grounded, N is an integer larger than or equal to 2, and two ends of the storage device comprises a first node and a second node respectively, wherein the X input ports of the X power conversion circuits are coupled in parallel, the X output ports of the X power conversion circuits are coupled in parallel; and X clamping circuit assemblies, wherein each of the X clamping circuit assemblies comprises N clamping circuits for absorbing a peak voltage generated at two ends of the third switch of the corresponding power conversion circuit, each of the N clamping circuits comprises at least one absorbing capacitor and at least one absorbing diode and has a first terminal, a second terminal and a third terminal, the first and second terminals are electrically connected to the two ends of the corresponding third switch respectively, the at least one absorbing capacitor and the at least one absorbing diode are serially coupled between the first and second terminals for absorbing a peak voltage generated at the two ends of the corresponding third switch, and the third terminal is electrically connected to the corresponding first node or the input port.