High-power high-frequency auxiliary power supply system and control method

Abstract

The invention discloses a high-power high-frequency auxiliary power supply system and a control method. The high-power high-frequency auxiliary power supply system comprises a signal acquisition board, a first CPU board, a second CPU board, a pulse board, a power supply board and a main circuit, the main circuit comprises two groups of high-frequency DCDC isolation circuits, a two-level three-phase INV circuit and a filter circuit; the two groups of high-frequency DCDC isolation circuits comprise a first single-group high-frequency DCDC isolation circuit and a second single-group high-frequency DCDC isolation circuit; the output end of the first single-group high-frequency DCDC isolation circuit and the output end of the second single-group high-frequency DCDC isolation circuit are connected with the input end of the two-level three-phase INV circuit, and a stable direct-current input power supply is provided for the two-level three-phase INV circuit. The filter circuit provides the filtered three-phase alternating current for a load and provides stable three-phase alternating current for the load; two groups of high-frequency DCDC isolation circuits are adopted for input series connection and output parallel connection, a single group of high-frequency DCDC isolation circuits adopts a three-level Boost circuit and a full-bridge LLC resonance rectification circuit, and the rated power of the high-frequency auxiliary power supply system is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the field of rail transportation and relates to a high-power high-frequency auxiliary power supply system and a control method. Background Art

[0002] In recent years, my country's rail transit industry has experienced rapid development, and new locomotives have placed higher demands on the efficiency, size, and weight of onboard converters. Locomotive auxiliary power supplies are crucial for ensuring stable and comfortable train operation, providing power to onboard auxiliary electrical equipment such as cooling fans, air compressors, air conditioners, electric heaters, ventilators, and information displays. Traditional power-frequency auxiliary power supplies, due to their large size, heavy weight, and low power transmission efficiency, are becoming increasingly vulnerable. This is contrary to the concept of high efficiency and environmental protection, and will be phased out. High-frequency auxiliary power supplies utilize high-frequency soft-switching technology, offering advantages such as high efficiency, high power density, and high performance. Compared to power-frequency auxiliary power supplies of the same capacity, they can reduce weight by more than half and increase efficiency by over 3%, representing the future of next-generation onboard auxiliary power supplies.

[0003] Prior art 1: The mainstream of the prior art is the industrial frequency isolated auxiliary power supply, that is, the DC input is converted into three-phase AC through the inverter circuit, and the three-phase AC is isolated by the industrial frequency transformer to supply power to the load.

[0004] Disadvantages of the existing technology 1: The power frequency isolation auxiliary power supply circuit is simple, and the input high voltage and output low voltage are isolated by the power frequency transformer. However, the isolation transformer is large in size, heavy in weight, and low in power, and will gradually be replaced by high-frequency auxiliary.

[0005] Prior art 2: The high-frequency auxiliary power supply is usually divided into three levels: the first level is voltage stabilization, the second level is high-frequency isolation, and the third level is three-phase inverter. The first-level voltage stabilization circuit and the second-level high-frequency isolation circuit can be defined as a single-group high-frequency DCDC isolation circuit.

[0006] The existing high-frequency auxiliary power supply solution is a single-group high-frequency DCDC isolation circuit, and the first-stage voltage regulation is a three-level Buck circuit. After reducing the input voltage, it is isolated at high frequency through a full-bridge LLC resonant rectifier circuit, and then converted into three-phase AC through a three-phase inverter circuit to power the load.

[0007] Disadvantages of the second prior art:

[0008] Since the first-stage voltage regulation adopts a three-level Buck circuit, for the same power, the lower the voltage, the greater the current. However, due to the heat dissipation of the high-frequency transformer components in the high-frequency isolation circuit, the greater the current, the more serious the heat. At the same time, with a single-group circuit structure, it is difficult for the high-frequency auxiliary power supply to further increase the power. Summary of the Invention

[0009] In order to solve the above problems, the technical solution adopted by the present invention is: a high-power high-frequency auxiliary power supply system, comprising:

[0010] Signal acquisition board, first CPU board, second CPU board, pulse board, power supply board and main circuit;

[0011] The main circuit includes two groups of high-frequency DCDC isolation circuits, a two-level three-phase INV circuit and a filter circuit;

[0012] The two groups of high-frequency DCDC isolation circuits include a first single group of high-frequency DCDC isolation circuits and a second single group of high-frequency DCDC isolation circuits;

[0013] The input ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in series;

[0014] The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in parallel;

[0015] The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected to the input end of the two-level three-phase INV circuit to provide a stable DC input power supply for the two-level three-phase INV circuit;

[0016] The output end of the two-level three-phase INV circuit is connected to the input end of the filter circuit.

[0017] The filtering circuit provides the filtered three-phase AC power to the load, thereby providing the load with stable three-phase AC power;

[0018] The signal board is used to collect the current signal and voltage signal of the main circuit;

[0019] The first CPU board is configured to output a first pulse signal based on the current signal and the voltage signal transmitted by the signal board;

[0020] The pulse board: based on the first pulse signal output by the first CPU board, controls the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit;

[0021] The second CPU board is used to output a second pulse signal based on the current signal and voltage signal transmitted by the signal board;

[0022] The pulse board controls the two-level three-phase INV circuit based on the second pulse signal transmitted by the second CPU board.

[0023] Furthermore: the first single-group high-frequency DCDC isolation circuit includes a first three-level Boost circuit and a first full-bridge LLC resonant rectifier circuit;

[0024] The first three-level Boost circuit is connected to a first full-bridge LLC resonant rectifier circuit;

[0025] The second single-group high-frequency DCDC isolation circuit includes a second three-level Boost circuit and a second full-bridge LLC resonant rectifier circuit;

[0026] The second three-level Boost circuit is connected to the second full-bridge LLC resonant rectifier circuit;

[0027] The first three-level Boost circuit includes a first inductor L B , first IGBTP1, second IGBTP2, first diode D1, second diode D2, first capacitor C 11 and the second capacitor C 12 ;

[0028] The first inductor L B One end is connected to the anode end of the first diode D1 and one end of the first IGBTP1;

[0029] The cathode end of the first diode D1 is connected to the first capacitor C 11 One end is connected;

[0030] The other end of the first IGBTP1 is connected to one end of the second IGBTP2 and the first capacitor C 11 The other end, the second capacitor C 12 One end is connected;

[0031] The other end of the second IGBTP2 is connected to the anode end of the second diode D2, and the cathode end of the second diode D2 is connected to the second capacitor C 12 The other end is connected;

[0032] The first full-bridge LLC resonant rectifier circuit includes a single-phase full-bridge inverter, a transformer T1, a resonant capacitor C r1 , a fifth diode D5, a sixth diode D6, a seventh diode D7 and an eighth diode D8;

[0033] The two ends of the primary side of the transformer T1 are connected through the resonant capacitor C r1 Connected to a single-phase full-bridge inverter;

[0034] One end of the secondary side of the transformer T1 is connected to the anode end of the fifth diode D5 and the anode end of the seventh diode D7.

[0035] The other end of the secondary side of the transformer T1 is connected to the anode end of the eighth diode D8 and the anode end of the sixth diode D6;

[0036] The second full-bridge LLC resonant rectifier circuit has the same structure as the first full-bridge LLC resonant rectifier circuit.

[0037] The second three-level Boost circuit comprises a third IGBT P3, a fourth IGBT P4, a third diode D3, a fourth diode D4, a third capacitor C 13 and a fourth capacitor C 14 .

[0038] One end of the third IGBT P3 is connected to the first three-level Boost circuit, and the anode end of the third diode D3 is connected.

[0039] The cathode end of the third diode D3 is connected to one end of the third capacitor C 13 .

[0040] The other end of the third IGBT P3 is connected to one end of the fourth IGBT P4, the other end of the third capacitor C 13 , and one end of the fourth capacitor C 14 .

[0041] The other end of the fourth IGBT P4 is connected to the anode end of the fourth diode D4, and the cathode end of the fourth diode D4 is connected to the other end of the fourth capacitor C 14 .

[0042] Further, the two-level three-phase INV circuit comprises a fifth capacitor and a three-phase full-bridge inverter circuit; the fifth capacitor and the three-phase full-bridge inverter circuit are connected in parallel.

[0043] Further, the filter circuit comprises a three-phase inductor and a three-phase capacitor connected;

[0044] The three-phase inductor comprises a second inductor, a third inductor, and a fourth inductor;

[0045] The three-phase capacitor comprises a sixth capacitor, a seventh capacitor, and an eighth capacitor;

[0046] One end of the second inductor, the third inductor, and the fourth inductor is respectively connected to the output of the three-phase full-bridge inverter circuit;

[0047] The other end of the second inductor is connected to one end of the eighth capacitor;

[0048] The other end of the third inductor is connected to one end of the seventh capacitor;

[0049] The other end of the fourth inductor is connected to one end of the sixth capacitor;

[0050] The other ends of the sixth capacitor, the seventh capacitor, and the eighth capacitor are connected.

[0051] Further: According to any one of the control methods for a high-power high-frequency auxiliary power supply system, the control process of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit is as follows:

[0052] Based on the system startup controller G LLC , the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started first,

[0053] When the system starts controller G LLC After gradually increasing from the narrowest pulse to 0.5, the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started, and the first three-level Boost circuit and the second three-level Boost circuit begin to work;

[0054] The control of the first three-level Boost circuit and the second three-level Boost circuit is achieved by a voltage-current dual closed-loop controller and an input voltage balancing controller;

[0055] Voltage and current dual closed-loop controller to achieve the voltage U across the fifth capacitor mid Stable and fast control;

[0056] The voltage and current dual closed-loop controller includes a voltage outer loop regulator G u and the current inner loop regulator G i ;

[0057] Voltage outer loop regulator G u , used to realize the voltage U across the fifth capacitor mid Stability control, G u The input is the reference value U of the voltage across the fifth capacitor mid * With the sample value U mid The difference, G u The output of the first inductor L B Reference value of current I L * ;

[0058] Current inner loop regulator G i , used to realize the voltage U across the fifth capacitor mid Quick Control, G i The input is the first inductor L B Reference value of current I L * With the sample value I L The difference, G i The output is the duty cycle signal D;

[0059] Input voltage equalization controller, used to realize the voltage U across the first capacitor c11, the voltage U across the second capacitor c12 , the voltage U across the third capacitor c13 , the voltage U across the fourth capacitor c14 Pressure equalization control;

[0060] The input voltage balance controller includes a first regulator G n1 , the second regulator G n2 and the third regulator G n3 ;

[0061] First regulator G n1 , used to implement U c11 with U c12 The sum is equal to U c13 with U c14 The sum of G n1 The input is U c11 、U c12 After adding and U c13 、U c14 The difference after addition, G n1 The output is the duty cycle D e , duty cycle D and duty cycle D e Adding them together gives the duty cycle D1, and subtracting them gives the duty cycle D2;

[0062] Second regulator G n2 , used to implement U c11 with U c12 Equal, G n2 The input is U c11 with U c12 The difference, G n2 The output is the duty cycle D e1 , duty cycle D1 and duty cycle D e1 The duty cycle d1 of the first IGBTP1 is obtained by adding D1 and D e1 Subtracting the duty cycle d2 of the second IGBTP2;

[0063] The third regulator G n3 , used to implement U c13 with U c14 Equal, G n3 The input is U c13 with U c14 The difference, G n3 The output is the duty cycle D e2 , duty cycle D2 and duty cycle D e2 The duty cycle d3 of the third IGBTP3 is obtained by adding the duty cycle D2 and the duty cycle D e2 Subtracting the duty cycle d4 of the fourth IGBTP4;

[0064] The voltage-current dual closed-loop controller and the input voltage balancing controller output duty cycles d1 and d2 that drive IGBTP1 and IGBTP2 of the first three-level Boost circuit via the first PWM generator; the output duty cycles d3 and d4 that drive IGBTP3 and IGBTP4 of the second three-level Boost circuit via the second PWM generator.

[0065] Furthermore: the voltage outer loop regulator G u , current inner loop regulator G i , first regulator G n1 , Second adjustment G n2 , the third regulator G n3 Both are proportional-integral controllers.

[0066] Further: According to any one of the control methods of a high-power high-frequency auxiliary power supply system, the method comprises the following steps: the control of the two-level three-phase INV circuit is realized by a voltage-current dual closed-loop controller to realize the voltage U across the second inductor and the third inductor. ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Stable and fast control,

[0067] The voltage and current dual closed-loop controller includes a first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , the first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 ;

[0068] The first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca stability control;

[0069] The voltage U across the actual second inductor and the third inductor in the filter circuit ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca The d-axis voltage U is obtained by converting the abc coordinate system to the dq coordinate system. d and q-axis voltage U q , through the first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 Make adjustments;

[0070] The process of adjusting the voltage by the outer loop controller is as follows:

[0071] The d-axis voltage U d * and d-axis reference voltage U d The difference between the two is used as the first voltage outer loop regulator G udq1 The input and output are the d-axis reference current i d * ;

[0072] The q-axis voltage U q * With q-axis reference voltage U q The difference between the two is used as the second voltage outer loop regulator G udq2 The input and output are q-axis reference current i q * ;

[0073] The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Quick control;

[0074] The actual current i output by the second inductor in the filter circuit a , the current i output by the third inductor b , the current i output by the fourth inductor c After the abc coordinate system is converted to the dq coordinate system, the actual d-axis current i is obtained. d and the q-axis actual current i q , through the first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 Make adjustments;

[0075] The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 The adjustment process is as follows:

[0076] The d-axis reference current i d * The actual current i of the d-axis d Make a difference, as the first current inner loop regulator G idq1 The input is d-axis voltage, and the output is d-axis voltage;

[0077] The q-axis reference current i q* The actual current i of the q axis q Make a difference and use it as the second current inner loop regulator G idq2 The input is q-axis voltage, and the output is q-axis voltage;

[0078] After converting the d-axis voltage and q-axis voltage to the abc coordinate system through the dq coordinate system, the three-phase voltage is obtained;

[0079] The three-phase voltage is compared with the actual voltage U of the fifth capacitor in the two-level three-phase INV circuit. cmid The SVPWM generator generates pulses to drive the main circuit switching devices, thereby controlling the two-level three-phase INV circuit.

[0080] Furthermore, the first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 , the first voltage outer loop regulator G udq1 and the second voltage outer loop regulator G udq2 Both are proportional-integral controllers.

[0081] The present invention provides a high-power, high-frequency auxiliary power supply system and control method, which has the following advantages:

[0082] In order to increase the rated capacity of the high-frequency auxiliary power supply system, two groups of high-frequency DCDC isolation circuits are used with inputs in series and outputs in parallel. A single group of high-frequency DCDC isolation circuits uses a three-level Boost circuit and a full-bridge LLC resonant rectifier circuit, which greatly improves the rated power of the high-frequency auxiliary power supply system.

[0083] Compared with a single-group high-frequency DCDC isolation circuit, the control hardware is not increased, and the control of two groups of high-frequency DCDC isolation circuits is realized in the first CPU board;

[0084] The control method adds an input voltage balancing controller and a system startup controller based on the first three-level Boost circuit, the second three-level Boost circuit voltage and current dual closed-loop controller and the full-bridge LLC resonant rectifier circuit controller to ensure stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0086] Figure 1 It is a schematic diagram of a high-power, high-frequency auxiliary power supply system;

[0087] Figure 2 It is a control method for two groups of high-frequency DCDC isolation circuits;

[0088] Figure 3 It is a two-level three-phase INV circuit control method. DETAILED DESCRIPTION

[0089] It should be noted that, unless there is any conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0090] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0091] Figure 1 It is a schematic diagram of a high-power, high-frequency auxiliary power supply system;

[0092] A high-power, high-frequency auxiliary power supply system, comprising:

[0093] Signal acquisition board, first CPU board, second CPU board, pulse board, power supply board and main circuit;

[0094] The main circuit includes two groups of high-frequency DCDC isolation circuits, a two-level three-phase INV circuit and a filter circuit;

[0095] The two groups of high-frequency DCDC isolation circuits include a first single group of high-frequency DCDC isolation circuits and a second single group of high-frequency DCDC isolation circuits;

[0096] The input ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in series;

[0097] The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in parallel;

[0098] The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected to the input end of the two-level three-phase INV circuit to provide a stable DC input power supply for the two-level three-phase INV circuit;

[0099] The output end of the two-level three-phase INV circuit is connected to the input end of the filter circuit.

[0100] The filtering circuit provides the filtered three-phase AC power to the load, thereby providing the load with stable three-phase AC power;

[0101] The signal board is used to collect the current signal and voltage signal of the main circuit;

[0102] The first CPU board is configured to output a first pulse signal based on the current signal and the voltage signal transmitted by the signal board;

[0103] The pulse board: based on the first pulse signal output by the first CPU board, controls the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit;

[0104] The second CPU board is used to output a second pulse signal based on the current signal and voltage signal transmitted by the signal board;

[0105] The pulse board controls the two-level three-phase INV circuit based on the second pulse signal transmitted by the second CPU board.

[0106] Furthermore: the first single-group high-frequency DCDC isolation circuit includes a first three-level Boost circuit and a first full-bridge LLC resonant rectifier circuit;

[0107] The first three-level Boost circuit is connected to a first full-bridge LLC resonant rectifier circuit;

[0108] The second single-group high-frequency DCDC isolation circuit includes a second three-level Boost circuit and a second full-bridge LLC resonant rectifier circuit;

[0109] The second three-level Boost circuit is connected to the second full-bridge LLC resonant rectifier circuit;

[0110] The first three-level Boost circuit includes a first inductor L B , first IGBT P1, second IGBT P2, first diode D1, second diode D2, first capacitor C 11 and the second capacitor C 12 ;

[0111] The first inductor L B One end is connected to the anode end of the first diode D1 and one end of the first IGBTP1;

[0112] The cathode end of the first diode D1 is connected to the first capacitor C 11 One end is connected;

[0113] The other end of the first IGBTP1 is connected to one end of the second IGBTP2 and the first capacitor C 11 The other end, the second capacitor C 12 One end is connected;

[0114] The other end of the second IGBTP2 is connected to the anode end of the second diode D2, and the cathode end of the second diode D2 is connected to the second capacitor C 12 The other end is connected;

[0115] The first full-bridge LLC resonant rectifier circuit includes a single-phase full-bridge inverter, a transformer T1, a resonant capacitor C r1 , a fifth diode D5, a sixth diode D6, a seventh diode D7 and an eighth diode D8;

[0116] The two ends of the primary side of the transformer T1 are connected through the resonant capacitor C r1 Connected to a single-phase full-bridge inverter;

[0117] One end of the secondary side of the transformer T1 is connected to the anode end of the fifth diode D5 and the anode end of the seventh diode D7.

[0118] The other end of the secondary side of the transformer T1 is connected to the anode end of the eighth diode D8 and the anode end of the sixth diode D6;

[0119] The second full-bridge LLC resonant rectifier circuit has the same structure as the first full-bridge LLC resonant rectifier circuit;

[0120] The second three-level Boost circuit includes a third IGBTP3, a fourth IGBTP4, a third diode D3, a fourth diode D4, a third capacitor C 13 and the fourth capacitor C 14 ;

[0121] One end of the third IGBTP3 is connected to the first three-level Boost circuit, and the anode end of the third diode D3 is connected;

[0122] The cathode end of the third diode D3 and the third capacitor C 13 One end is connected;

[0123] The other end of the third IGBTP3 is connected to one end of the fourth IGBTP4 and the third capacitor C 13 The other end, the fourth capacitor C 14 One end is connected;

[0124] The other end of the fourth IGBTP4 is connected to the anode end of the fourth diode D4, and the cathode end of the fourth diode D4 is connected to the fourth capacitor C 14 The other end is connected.

[0125] Furthermore: the two-level three-phase INV circuit includes a fifth capacitor and a three-phase full-bridge inverter circuit; the fifth capacitor and the three-phase full-bridge inverter circuit are connected in parallel.

[0126] Further: the filtering circuit includes three-phase inductors and three-phase capacitors connected;

[0127] The three-phase inductor includes a second inductor, a third inductor and a fourth inductor;

[0128] The three-phase capacitor includes a sixth capacitor, a seventh capacitor and an eighth capacitor;

[0129] One end of the second inductor, the third inductor and the fourth inductor are respectively connected to the three-phase full-bridge inverter circuit;

[0130] The other end of the second inductor is connected to one end of the eighth capacitor;

[0131] The other end of the third inductor is connected to one end of the seventh capacitor;

[0132] The other end of the fourth inductor is connected to one end of the sixth capacitor;

[0133] The other ends of the sixth capacitor, the seventh capacitor and the eighth capacitor are connected.

[0134] In the main circuit, two high-frequency DC-DC isolation circuit inputs are connected in series, and two high-frequency DC-DC isolation circuit outputs are connected in parallel, powering a two-level three-phase INV circuit. The two-level three-phase INV circuit outputs three-phase AC power, which is filtered by LC and supplied to the load. The system uses T1 and T2 to achieve electrical isolation between the high-voltage input and the low-voltage output.

[0135] In terms of control hardware, the signal board collects 12 analog signals and outputs them to the first CPU board and the second CPU board. The first CPU board and the second CPU board output pulse signals to control the main circuit switching devices (IGBT). After conditioning by the pulse board, the switching devices are driven. The power supply board supplies power to the signal acquisition board, the first CPU board and the second CPU board, as well as the pulse board.

[0136] In terms of control method, the first CPU board controls two groups of high-frequency DCDC isolation circuits to provide stable input power for the two-level three-phase INV circuit. The second CPU board controls the two-level three-phase INV circuit to provide stable three-phase AC power for the load.

[0137] Figure 2 It is a control method for two groups of high-frequency DCDC isolation circuits;

[0138] A control method for a high-power, high-frequency auxiliary power supply system according to any one of the above methods comprises:

[0139] The control process of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit is as follows:

[0140] Based on the system startup controller G LLC , the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started first,

[0141] When the system starts controller G LLC After gradually increasing from the narrowest pulse to 0.5, the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started, and the first three-level Boost circuit and the second three-level Boost circuit begin to work;

[0142] The control of the first three-level Boost circuit and the second three-level Boost circuit is achieved by a voltage-current dual closed-loop controller and an input voltage balancing controller;

[0143] Voltage and current dual closed-loop controller to achieve the voltage U across the fifth capacitor mid Stable and fast control; the voltage and current dual closed-loop controller includes a voltage outer loop regulator G u and flow inner ring regulator G i ;

[0144] Voltage outer loop regulator G u , used to realize the voltage U across the fifth capacitor mid Stability control, G u The input is the reference value U of the voltage across the fifth capacitor mid * With the sample value U mid The difference, G u The output of the first inductor L B Reference value of current I L * ;

[0145] Current inner loop regulator G i , used to realize the voltage U across the fifth capacitor mid Quick Control, G i The input is the first inductor L B Reference value of current I L * With the sample value I L The difference, G i The output is the duty cycle signal D;

[0146] Input voltage equalization controller, used to realize the voltage U across the first capacitor c11 , the voltage U across the second capacitor c12 , the voltage U across the third capacitor c13 , the voltage U across the fourth capacitorc14 Pressure equalization control;

[0147] The input voltage balance controller includes a first regulator G n1 , the second regulator G n2 and the third regulator G n3 ;

[0148] First regulator G n1 , used to implement U c11 with U c12 The sum is equal to U c13 with U c14 The sum of G n1 The input is U c11 、U c12 After adding and U c13 、U c14 The difference after addition, G n1 The output is the duty cycle D e , duty cycle D and duty cycle D e Adding them together gives the duty cycle D1, and subtracting them gives the duty cycle D2;

[0149] Second regulator G n2 , used to implement U c11 with U c12 Equal, G n2 The input is U c11 with U c12 The difference, G n2 The output is the duty cycle D e1 , duty cycle D1 and duty cycle D e1 The duty cycle d1 of the first IGBTP1 is obtained by adding D1 and D e1 Subtracting the duty cycle d2 of the second IGBTP2;

[0150] The third regulator G n3 , used to implement U c13 with U c14 Equal, G n3 The input is U c13 with U c14 The difference, G n3 The output is the duty cycle D e2 , duty cycle D2 and duty cycle D e2 The duty cycle d3 of the third IGBTP3 is obtained by adding the duty cycle D2 and the duty cycle D e2 Subtracting the duty cycle d4 of the fourth IGBTP4;

[0151] The voltage-current dual closed-loop controller and the input voltage balancing controller output duty cycles d1 and d2 to drive IGBTP1 and IGBTP2 of the first three-level Boost circuit through the first PWM generator; the output duty cycles d3 and d4 are obtained through the second PWM generator to drive IGBTP3 and IGBTP4 of the second three-level Boost circuit.

[0152] The voltage outer loop regulator G u , current inner loop regulator G i , first regulator G n1 , the second regulator G n2 , the third regulator G n3 Both are proportional-integral controllers.

[0153] Figure 3 It is a two-level three-phase INV circuit control method;

[0154] A control method for a high-power, high-frequency auxiliary power supply system according to any one of the above methods comprises the following steps:

[0155] The control of the two-level three-phase INV circuit is realized by a voltage-current dual closed-loop controller to realize the voltage U across the second inductor and the third inductor. ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Stable and fast control,

[0156] The voltage and current dual closed-loop controller includes a first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , the first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 ;

[0157] The first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca stability control;

[0158] The voltage U across the actual second inductor and the third inductor in the filter circuit ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca The d-axis voltage U is obtained by converting the abc coordinate system to the dq coordinate system. dand q-axis voltage U q , the first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 Make adjustments;

[0159] The process of adjusting the voltage by the outer loop controller is as follows:

[0160] The d-axis voltage U d * and d-axis reference voltage U d The difference between the two is used as the first voltage outer loop regulator G udq1 The input and output are the d-axis reference current i d * ;

[0161] The q-axis voltage U q * With q-axis reference voltage U q The difference between the two is used as the second voltage outer loop regulator G udq2 The input and output are q-axis reference current i q * ;

[0162] The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Quick control;

[0163] The actual current i output by the second inductor in the filter circuit a , the current i output by the third inductor b , the current i output by the fourth inductor c After the abc coordinate system is converted to the dq coordinate system, the actual d-axis current i is obtained. d and the q-axis actual current i q , through the first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 Make adjustments;

[0164] The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 The adjustment process is as follows:

[0165] The d-axis reference current i d * The actual current i of the d-axis d Make a difference, as the first current inner loop regulator Gidq1 The input is d-axis voltage, and the output is d-axis voltage;

[0166] The q-axis reference current i q * The actual current i of the q axis q Make a difference and use it as the second current inner loop regulator G idq2 The input is q-axis voltage, and the output is q-axis voltage;

[0167] After converting the d-axis voltage and q-axis voltage to the abc coordinate system through the dq coordinate system, the three-phase voltage is obtained;

[0168] The three-phase voltage is compared with the actual voltage U of the fifth capacitor in the two-level three-phase INV circuit. cmid The SVPWM generator generates pulses to drive the main circuit switching devices, thereby controlling the two-level three-phase INV circuit.

[0169] The first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 , the first voltage outer loop regulator G udq1 and the second voltage outer loop regulator G udq2 Both are proportional-integral controllers.

[0170] The three-level Boost circuit in the main circuit of the present invention can be replaced by a three-level Buck circuit, and the full-bridge LLC resonant rectifier circuit can be replaced by a half-bridge LLC resonant rectifier circuit;

[0171] The control hardware can control the first three-level Boost circuit, the second three-level Boost circuit and the first full-bridge LLC resonant rectifier circuit, and the second full-bridge LLC resonant rectifier circuit with two CPU boards, such as one CPU board for Boost1 / 2 and one CPU board for full-bridge LLC resonant rectifier circuit 1 / 2, or one CPU board for Boost1 and full-bridge LLC1 resonant rectifier circuit 1 and one CPU board for Boost2 and full-bridge LLC2 resonant rectifier circuit 2.

[0172] The first single-group high-frequency DCDC isolation circuit includes a first three-level Buck circuit and a first half-bridge LLC resonant rectifier circuit;

[0173] The first three-level Buck circuit is connected to the first half-bridge LLC resonant rectifier circuit;

[0174] The second single-group high-frequency DCDC isolation circuit includes a second three-level Buck circuit and a second half-bridge LLC resonant rectifier circuit;

[0175] The second three-level Buck circuit is connected to the second half-bridge LLC resonant rectifier circuit;

[0176] The first three-level Buck circuit and the second three-level Buck circuit are connected in series;

[0177] The first half-bridge LLC resonant rectifier circuit and the second half-bridge LLC resonant rectifier circuit are connected in parallel.

[0178] Furthermore: the first single-group high-frequency DCDC isolation circuit includes a first three-level boost circuit and a first half-bridge LLC resonant rectifier circuit;

[0179] The first three-level boost circuit is connected to a first half-bridge LLC resonant rectifier circuit;

[0180] The second single-group high-frequency DCDC isolation circuit includes a second three-level boost circuit and a second half-bridge LLC resonant rectifier circuit;

[0181] The second three-level boost circuit is connected to the second half-bridge LLC resonant rectifier circuit;

[0182] The first three-level boost circuit and the second three-level boost circuit are connected in series;

[0183] The first half-bridge LLC resonant rectifier circuit and the second half-bridge LLC resonant rectifier circuit are connected in parallel.

[0184] Furthermore: the first single-group high-frequency DCDC isolation circuit includes a first three-level Buck circuit and a first full-bridge LLC resonant rectifier circuit;

[0185] The first three-level Buck circuit is connected to the first full-bridge LLC resonant rectifier circuit;

[0186] The second single-group high-frequency DCDC isolation circuit includes a second three-level Buck circuit and a second full-bridge LLC resonant rectifier circuit;

[0187] The second three-level Buck circuit is connected to the second full-bridge LLC resonant rectifier circuit;

[0188] The first three-level Buck circuit and the second three-level Buck circuit are connected in series;

[0189] The first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are connected in parallel.

[0190] In order to increase the rated capacity of the high-frequency auxiliary power supply system, the present invention adopts two groups of high-frequency DCDC isolation circuits with series input and parallel output. A single group of high-frequency DCDC isolation circuit adopts a three-level Boost circuit and a full-bridge LLC resonant rectifier circuit, which greatly improves the rated power of the high-frequency auxiliary power supply system.

[0191] Compared with a single-group high-frequency DCDC isolation circuit, the control hardware has not been increased, and the control of two groups of high-frequency DCDC isolation circuits is implemented in the first CPU board; the control method adds an input voltage balancing controller, a full-bridge LLC resonant rectifier circuit controller and a system startup controller to ensure stable operation of the system.

[0192] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-power, high-frequency auxiliary power supply system, characterized by: include: Signal acquisition board, first CPU board, second CPU board, pulse board, power supply board and main circuit; The main circuit includes two groups of high-frequency DCDC isolation circuits, a two-level three-phase INV circuit and a filter circuit; The two groups of high-frequency DCDC isolation circuits include a first single group of high-frequency DCDC isolation circuits and a second single group of high-frequency DCDC isolation circuits; The input ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in series; The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected in parallel; The output ends of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit are connected to the input end of the two-level three-phase INV circuit to provide a stable DC input power supply for the two-level three-phase INV circuit; The output end of the two-level three-phase INV circuit is connected to the input end of the filter circuit. The filtering circuit provides the filtered three-phase AC power to the load, thereby providing the load with stable three-phase AC power; The signal board is used to collect the current signal and voltage signal of the main circuit; The first CPU board is configured to output a first pulse signal based on the current signal and the voltage signal transmitted by the signal board; The pulse board: based on the first pulse signal output by the first CPU board, controls the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit; The second CPU board is used to output a second pulse signal based on the current signal and voltage signal transmitted by the signal board; The pulse board controls the two-level three-phase INV circuit based on the second pulse signal transmitted by the second CPU board.

2. A high-power, high-frequency auxiliary power supply system according to claim 1, characterized in that: The first single-group high-frequency DCDC isolation circuit includes a first three-level Boost circuit and a first full-bridge LLC resonant rectifier circuit; The first three-level Boost circuit is connected to a first full-bridge LLC resonant rectifier circuit; The second single-group high-frequency DCDC isolation circuit includes a second three-level Boost circuit and a second full-bridge LLC resonant rectifier circuit; The second three-level Boost circuit is connected to the second full-bridge LLC resonant rectifier circuit; The first three-level Boost circuit includes a first inductor L B , first IGBTP1, second IGBTP2, first diode D1, second diode D2, first capacitor C 11 and the second capacitor C 12 ; The first inductor L B One end is connected to the anode end of the first diode D1 and one end of the first IGBTP1; The cathode end of the first diode D1 is connected to the first capacitor C 11 One end is connected; The other end of the first IGBTP1 is connected to one end of the second IGBTP2 and the first capacitor C 11 The other end, the second capacitor C 12 One end is connected; The other end of the second IGBTP2 is connected to the anode end of the second diode D2, and the cathode end of the second diode D2 is connected to the second capacitor C 12 The other end is connected; The first full-bridge LLC resonant rectifier circuit includes a single-phase full-bridge inverter, a transformer T1, a resonant capacitor C r1 , a fifth diode D5, a sixth diode D6, a seventh diode D7 and an eighth diode D8; The two ends of the primary side of the transformer T1 are connected through the resonant capacitor C r1 Connected to a single-phase full-bridge inverter; One end of the secondary side of the transformer T1 is connected to the anode end of the fifth diode D5 and the anode end of the seventh diode D7. The other end of the secondary side of the transformer T1 is connected to the anode end of the eighth diode D8 and the anode end of the sixth diode D6; The second full-bridge LLC resonant rectifier circuit has the same structure as the first full-bridge LLC resonant rectifier circuit; The second three-level Boost circuit includes a third IGBTP3, a fourth IGBTP4, a third diode D3, a fourth diode D4, a third capacitor C 13 and the fourth capacitor C 14 ; One end of the third IGBTP3 is connected to the first three-level Boost circuit, and the anode end of the third diode D3 is connected; The cathode end of the third diode D3 and the third capacitor C 13 One end is connected; The other end of the third IGBTP3 is connected to one end of the fourth IGBTP4 and the third capacitor C 13 The other end, the fourth capacitor C 14 One end is connected; The other end of the fourth IGBTP4 is connected to the anode end of the fourth diode D4, and the cathode end of the fourth diode D4 is connected to the fourth capacitor C 14 The other end is connected.

3. A high-power, high-frequency auxiliary power supply system according to claim 1, characterized in that: The two-level three-phase INV circuit includes a fifth capacitor and a three-phase full-bridge inverter circuit; the fifth capacitor and the three-phase full-bridge inverter circuit are connected in parallel.

4. A high-power, high-frequency auxiliary power supply system according to claim 1, characterized in that: The filter circuit includes three-phase inductors and three-phase capacitors connected; The three-phase inductor includes a second inductor, a third inductor and a fourth inductor; The three-phase capacitor includes a sixth capacitor, a seventh capacitor and an eighth capacitor; One end of the second inductor, the third inductor and the fourth inductor are respectively connected to the output of the three-phase full-bridge inverter circuit; The other end of the second inductor is connected to one end of the eighth capacitor; The other end of the third inductor is connected to one end of the seventh capacitor; The other end of the fourth inductor is connected to one end of the sixth capacitor; The other ends of the sixth capacitor, the seventh capacitor and the eighth capacitor are connected.

5. A control method for a high-power, high-frequency auxiliary power supply system according to any one of claims 1 to 4, characterized in that: include: The control process of the first single-group high-frequency DCDC isolation circuit and the second single-group high-frequency DCDC isolation circuit is as follows: Based on the system startup controller G LLC , the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started first, When the system starts controller G LLC After gradually increasing from the narrowest pulse to 0.5, the first full-bridge LLC resonant rectifier circuit and the second full-bridge LLC resonant rectifier circuit are started, and the first three-level Boost circuit and the second three-level Boost circuit begin to work; The control of the first three-level Boost circuit and the second three-level Boost circuit is achieved by a voltage-current dual closed-loop controller and an input voltage balancing controller; Voltage and current dual closed-loop controller to achieve the voltage U across the fifth capacitor mid Stable and fast control; The voltage and current dual closed-loop controller includes a voltage outer loop regulator G u and the current inner loop regulator G i ; Voltage outer loop regulator G u , used to realize the voltage U across the fifth capacitor mid Stability control, G u The input is the reference value U of the voltage across the fifth capacitor mid * With the sample value U mid The difference, G u The output of the first inductor L B Reference value of current I L * ; Current inner loop regulator G i , used to realize the voltage U across the fifth capacitor mid Quick Control, G i The input is the first inductor L B Reference value of current I L * With the sample value I L The difference, G i The output is the duty cycle signal D; Input voltage equalization controller, used to realize the voltage U across the first capacitor c11 , the voltage U across the second capacitor c12 , the voltage U across the third capacitor c13 , the voltage U across the fourth capacitor c14 Pressure equalization control; The input voltage balance controller includes a first regulator G n1 , the second regulator G n2 and the third regulator G n3 ; First regulator G n1 , used to implement U c11 with U c12 The sum is equal to U c13 with U c14 The sum of G n1 The input is U c11 、U c12 After adding and U c13 、U c14 The difference after addition, G n1 The output is the duty cycle D e , duty cycle D and duty cycle D e Adding them together gives the duty cycle D1, and subtracting them gives the duty cycle D2; Second regulator G n2 , used to implement U c11 with U c12 Equal, G n2 The input is U c11 with U c12 The difference, G n2 The output is the duty cycle D e1 , duty cycle D1 and duty cycle D e1 The duty cycle d1 of the first IGBTP1 is obtained by adding D1 and D e1 Subtracting the duty cycle d2 of the second IGBTP2; The third regulator G n3 , used to implement U c13 with U c14 Equal, G n3 The input is U c13 with U c14 The difference, G n3 The output is the duty cycle D e2 , duty cycle D2 and duty cycle D e2 The duty cycle d3 of the third IGBTP3 is obtained by adding the duty cycle D2 and the duty cycle D e2 Subtracting the duty cycle d4 of the fourth IGBTP4; The voltage-current dual closed-loop controller and the input voltage balancing controller output duty cycles d1 and d2 that drive IGBTP1 and IGBTP2 of the first three-level Boost circuit via the first PWM generator; the output duty cycles d3 and d4 that drive IGBTP3 and IGBTP4 of the second three-level Boost circuit via the second PWM generator.

6. The control method of a high-power high-frequency auxiliary power system according to claim 5, characterized in that: The voltage outer loop regulator G u , current inner loop regulator G i , first regulator G n1 , Second adjustment G n2 , the third regulator G n3 Both are proportional-integral controllers.

7. A control method for a high-power, high-frequency auxiliary power supply system according to any one of claims 1 to 4, characterized in that: The following steps are involved: The control of the two-level three-phase INV circuit is realized by a voltage-current dual closed-loop controller to realize the voltage U across the second inductor and the third inductor. ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Stable and fast control, The voltage and current dual closed-loop controller includes a first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , the first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 ; The first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca stability control; The voltage U across the actual second inductor and the third inductor in the filter circuit ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca The d-axis voltage U is obtained by converting the abc coordinate system to the dq coordinate system. d and q-axis voltage U q , through the first voltage outer loop regulator G udq1 , the second voltage outer loop regulator G udq2 Make adjustments; The process of adjusting the voltage by the outer loop controller is as follows: The d-axis voltage U d * and d-axis reference voltage U d The difference between the two is used as the first voltage outer loop regulator G udq1 The input and output are the d-axis reference current i d * ; The q-axis voltage U q * With q-axis reference voltage U q The difference between the two is used as the second voltage outer loop regulator G udq2 The input and output are q-axis reference current i q * ; The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 , used to realize the voltage U across the second inductor and the third inductor ab , the voltage U across the third inductor and the fourth inductor bc , the voltage U across the second inductor and the fourth inductor ca Quick control; The actual current i output by the second inductor in the filter circuit a , the current i output by the third inductor b , the current i output by the fourth inductor c After the abc coordinate system is converted to the dq coordinate system, the actual d-axis current i is obtained. d and the q-axis actual current i q , through the first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 Make adjustments; The first current inner loop regulator G idq1 and the second current inner loop regulator G idq2 The adjustment process is as follows: The d-axis reference current i d * The actual current i of the d-axis d Make a difference, as the first current inner loop regulator G idq1 The input is d-axis voltage, and the output is d-axis voltage; The q-axis reference current i q * The actual current i of the q axis q Make a difference and use it as the second current inner loop regulator G idq2 The input is q-axis voltage, and the output is q-axis voltage; After converting the d-axis voltage and q-axis voltage to the abc coordinate system through the dq coordinate system, the three-phase voltage is obtained; The three-phase voltage is compared with the actual voltage U of the fifth capacitor in the two-level three-phase INV circuit. cmid The SVPWM generator generates pulses to drive the main circuit switching devices, thereby controlling the two-level three-phase INV circuit.

8. A high-power, high-frequency auxiliary power supply system according to claim 7, characterized in that: The first current inner loop regulator G idq1 , the second current inner loop regulator G idq2 , the first voltage outer loop regulator G udq1 and the second voltage outer loop regulator G udq2 Both are proportional-integral controllers.

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