Wide-range efficient DCDC converter
By introducing an adjustable excitation inductance module and a single-pole double-throw relay into the DCDC converter, the inductance ratio and gain characteristics are changed, which solves the problems of limited voltage range and low efficiency of traditional DCDC converters and achieves more efficient voltage and frequency control.
Patent Information
- Application Number
- CN202423090168.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-09-09
- Estimated Expiration
- 2034-12-12
AI Technical Summary
The input and output voltage range of traditional full-bridge DCDC converters is limited, and the rectifier diodes lose their zero-current shutdown capability at low voltage or low power output, resulting in increased losses and reduced efficiency.
A wide-range and high-efficiency DC-DC converter is designed. It adopts an adjustable excitation inductor module and a regulation unit, including a single-pole double-throw relay. By changing the inductance ratio and gain characteristics of the excitation inductor, the output voltage range is expanded or the operating frequency range is narrowed. When the excitation inductance increases, the excitation current is reduced to reduce losses.
While expanding the output voltage range or narrowing the operating frequency range, the efficiency of the DCDC converter is improved and the excitation current and loss are reduced.
Smart Images
Figure CN223321981U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of DCDC converters, and more particularly to a wide-range and high-efficiency DCDC converter. Background Art
[0002] With the rapid development of new energy vehicles and energy storage, DC-DC converters have become widely used in photovoltaic charging and storage systems and vehicle-to-vehicle (V2G) systems. However, the magnetizing inductance of traditional full-bridge DC-DC converters limits the input and output voltage range. Furthermore, when operating at low voltage or low power, the rectifier diodes lose their zero-current shutdown capability, resulting in increased losses and reduced efficiency. Utility Model Content
[0003] The technical problem to be solved by the present invention is to provide a wide-range and high-efficiency DCDC converter in response to the above-mentioned defects of the prior art, which can increase the input and output voltage range while effectively improving the efficiency of the converter.
[0004] The technical solution adopted by the utility model to solve the technical problem is: constructing a wide range and high-efficiency DCDC converter, comprising: a transformer module, an adjustable excitation inductance module and a primary side module sequentially arranged on the primary side of the transformer module, and a secondary side module arranged on the secondary side of the transformer module;
[0005] The first end of the adjustable excitation inductance module is connected to the first output end of the primary module, the second end is connected to the second output end of the primary module, the third end is connected to the first end of the primary side of the transformer module, and the fourth end is connected to the second end of the primary side of the transformer module; the first input end of the secondary side module is connected to the first end of the secondary side of the transformer module, and the second input end is connected to the second end of the secondary side of the transformer module.
[0006] In the wide-range, high-efficiency DCDC converter described in the present utility model, the adjustable excitation inductor module includes an excitation inductor and an adjustment unit. The first end of the excitation inductor is connected to the first end of the primary side of the transformer module, and the second end or the third end of the excitation inductor is connected to the second end of the primary side of the transformer module via the adjustment unit. The third end of the excitation inductor is located between the first end and the second end of the excitation inductor.
[0007] In the wide-range and high-efficiency DCDC converter described in the present utility model, the regulating unit includes a single-pole double-throw relay, the moving contact of the single-pole double-throw relay is connected to the second end of the primary side of the transformer module, the first static contact is connected to the second end of the excitation inductor, and the second static contact is connected to the third end of the excitation inductor.
[0008] In the wide-range high-efficiency DCDC converter described in the present invention, the third end of the excitation inductor is a center tap of the excitation inductor.
[0009] In the wide-range and high-efficiency DCDC converter described in the present invention, the primary side module includes a first DC power supply network, a first filter network, a first switch network, and a first resonant network connected in sequence.
[0010] In the wide-range and high-efficiency DCDC converter of the present invention, the first switching network includes a first full-bridge switching tube network consisting of a first switching tube, a second switching tube, a third switching tube, and a fourth switching tube. The first end of the first full-bridge switching tube network is connected to the positive power supply of the first DC power supply network, the second end is connected to the negative power supply of the first DC power supply network, the third end is connected to the first end of the first resonant network, and the fourth end is connected to the second end of the first resonant network.
[0011] The first resonant network includes a first resonant capacitor and a first resonant inductor, the first end of the first resonant inductor is connected to the third end of the first full-bridge switch tube network, and the second end is connected to the first end of the primary side of the transformer module and the first end of the excitation inductor; the first end of the first resonant capacitor is connected to the fourth end of the first full-bridge switch tube network, and the second end is connected to the second end of the primary side of the transformer module.
[0012] In the wide-range and high-efficiency DCDC converter described in the present invention, the first filter network includes a first filter capacitor, a first end of the first filter capacitor is connected to the positive power supply of the first DC power supply network, and a second end is connected to the negative power supply of the first DC power supply network.
[0013] In the wide-range and high-efficiency DCDC converter described in the present invention, the secondary side module includes a second resonant network, a second switch network, a second filter network, and a second DC power supply network connected in sequence.
[0014] In the wide-range, high-efficiency DCDC converter described in the present invention, the second resonant network includes a second resonant inductor and a second resonant capacitor; the second switch network includes a second full-bridge switch tube network consisting of a fifth switch tube, a sixth switch tube, a seventh switch tube, and an eighth switch tube; the second resonant inductor and the second resonant capacitor are connected in series between the first end of the secondary side of the transformer module and the first end of the second full-bridge switch tube network, the second end of the second full-bridge switch tube network is connected to the second end of the secondary side of the transformer module, the third end is connected to the positive power supply of the second DC power supply network, and the fourth end is connected to the negative power supply of the second DC power supply network.
[0015] In the wide-range and high-efficiency DCDC converter described in the present invention, the secondary side module includes a rectifier network, a third filter network, and a load connected in sequence.
[0016] In the wide-range and high-efficiency DCDC converter described in the present invention, the rectifier network includes a full-bridge rectifier network consisting of a first diode, a second diode, a third diode, and a fourth diode. The first end of the full-bridge rectifier network is connected to the first end of the secondary side of the transformer module, the second end is connected to the second end of the secondary side of the transformer module, the third end is connected to the first end of the load, and the fourth end is connected to the second end of the load.
[0017] The wide-range and high-efficiency DCDC converter of the present invention can change the inductance ratio and gain characteristics by setting an adjustable excitation inductance module, thereby expanding the output voltage range when the operating frequency range is constant, or narrowing the operating frequency range when the output voltage range is constant. In addition, when the inductance of the adjustable excitation inductance module is increased, the excitation current can be reduced, the loss can be reduced, and the efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:
[0019] Figure 1 This is the principle block diagram of the wide range and high efficiency DCDC converter of the utility model;
[0020] Figure 2 This is a principle block diagram of a preferred embodiment of the wide-range and high-efficiency DCDC converter of the present utility model;
[0021] Figure 3 yes Figure 2 The circuit diagram of the wide range and high efficiency DCDC converter shown;
[0022] Figure 4 yes Figure 3 The power flow diagram of the wide range and high efficiency DCDC converter working in full-bridge mode is shown;
[0023] Figure 5 yes Figure 3 The power flow diagram of the wide range and high efficiency DCDC converter working in half-bridge mode is shown;
[0024] Figure 6 This is a principle block diagram of another preferred embodiment of the wide-range and high-efficiency DCDC converter of the present utility model;
[0025] Figure 7 yes Figure 6 The circuit diagram of the wide range and high efficiency DCDC converter is shown. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0027] Figure 1 This is the principle block diagram of the wide range and high efficiency DCDC converter of this utility model. Figure 1 As shown, the wide-range, high-efficiency DC-DC converter includes: a transformer module 10, an adjustable excitation inductor module 20 and a primary module 30 sequentially arranged on the primary side of the transformer module 10, and a secondary module 40 arranged on the secondary side of the transformer module 10. The adjustable excitation inductor module 20 has a first end connected to the first output end of the primary module 30, a second end connected to the second output end of the primary module 30, a third end connected to the first primary end of the transformer module 10, and a fourth end connected to the second primary end of the transformer module 10. The secondary module 40 has a first input end connected to the first secondary end of the transformer module 10, and a second input end connected to the second secondary end of the transformer module 10.
[0028] Here, the adjustable excitation inductance module 20 may adopt any suitable structure as long as the inductance thereof is adjustable.
[0029] In a preferred embodiment of the present invention, the transformer module 10 includes at least one transformer, preferably an ideal transformer having a magnetic core made of a highly permeable material (typically ferrite) and a relatively infinite excitation inductance. This is manifested in, but not limited to, transformer T1 having no air gap. In other preferred embodiments of the present invention, the transformer module 10 may also include, for example, two ideal transformers connected in series. Preferably, the excitation inductance of the transformer module 10 is relatively infinite, such that the equivalent excitation inductance of the transformer module 10, when connected in parallel with the excitation inductance Lm, is infinitely close to the inductance of the excitation inductance Lm.
[0030] In a preferred embodiment of the present invention, the primary module 30 and the secondary module 40 can employ the primary and secondary circuit configurations of any known DC-DC converter in the art. For example, when the wide-range, high-efficiency DC-DC converter is a bidirectional DC-DC converter, the primary module 30 can include a first DC power supply network, a first filter network, a first switch network, and a first resonant network connected in sequence, while the secondary module 40 can include a second resonant network, a second switch network, a second filter network, and a second DC power supply network connected in sequence. When the wide-range, high-efficiency DC-DC converter is a unidirectional DC-DC converter, the primary module 30 can include a first DC power supply network, a first filter network, a first switch network, and a first resonant network connected in sequence, while the secondary module 40 can include a rectifier network, a third filter network, and a load connected in sequence. Of course, in other preferred embodiments of the present invention, the primary module 30 and the secondary module 40 can omit the filter network or add other functional networks, for example. These configurations can be tailored to actual needs.
[0031] exist Figure 1 In the preferred embodiment shown, the adjustable excitation inductance module 20 includes an excitation inductance Lm and an adjustment unit 21, the first end of the excitation inductance Lm is connected to the first end of the primary side of the transformer module 10, and the second end or the third end of the excitation inductance Lm is connected to the second end of the primary side of the transformer module 10 via the adjustment unit 21; the third end of the excitation inductance Lm is located between the first end and the second end of the excitation inductance Lm.
[0032] In this preferred embodiment, the adjustment unit 21 can be any suitable switching device, such as a relay switch, an electronically controlled switch or a switching tube device, as long as it can connect the second end or the third end of the excitation inductance Lm to the second end of the primary side of the transformer module 10 through the adjustment unit 21. Since the third end of the excitation inductor Lm is located between the first and second ends thereof, for example, it is an intermediate tap, the adjustable excitation inductor module 20 actually causes the inductance of the excitation inductor Lm to be different. That is, when the second end of the excitation inductor Lm is connected to the second end of the primary side of the transformer module 10 via the adjustment unit 21 and when the second end of the excitation inductor Lm is connected to the second end of the primary side of the transformer module 10 via the adjustment unit 21, the actual inductance ratio of the wide-range and high-efficiency DC-DC converter of the present invention is different. Therefore, by changing the inductance ratio, the gain characteristic can be changed, thereby expanding the output voltage range when the operating frequency range is constant, or narrowing the operating frequency range when the output voltage range is constant. In addition, when the inductance of the excitation inductor Lm is increased, the excitation current can be reduced, the loss can be reduced, and the efficiency can be improved.
[0033] Figure 2This is a principle block diagram of a preferred embodiment of the wide-range and high-efficiency DCDC converter of the present utility model. Figure 3 yes Figure 2 The circuit diagram of the wide range and high efficiency DCDC converter is shown in FIG. Figure 2-3 In the preferred embodiment shown, the wide range and high efficiency DCDC converter is a bidirectional wide range and high efficiency DCDC converter. Figure 1-2 It can be seen that the wide range high efficiency DCDC converter includes: a transformer module 10, an adjustable excitation inductance module 20 and a primary side module 30 sequentially arranged on the primary side of the transformer module 10, and a secondary side module 40 arranged on the secondary side of the transformer module 10. Figure 2-3 In the preferred embodiment shown, the transformer module 10 includes a high-frequency transformer T1, which is preferably an ideal transformer, whose magnetic core is made of a high-magnetic-permeability material (commonly ferrite), and whose excitation inductance is relatively infinite. The process performance includes but is not limited to the transformer T1 not having an air gap.
[0034] The adjustable excitation inductance module 20 includes an excitation inductance Lm and an adjustment unit 21. The primary module 30 includes a DC power supply network 31, a first filter network 32, a first switch network 33, and a first resonant network 34 connected in sequence. The secondary module 40 includes a second resonant network 41, a second switch network 42, a second filter network 43, and a DC power supply network 44 connected in sequence.
[0035] Furthermore, if Figure 3 As shown, the DC power supply network 31 is a DC power supply V1, which can also be any other suitable DC power supply module, network, or unit, such as a battery module, a single-phase active power factor correction circuit, or a three-phase active power factor correction circuit. The DC power supply network 44 is a DC power supply V2, which can also be any other suitable DC power supply module, network, or unit, such as a battery module, a single-phase active power factor correction circuit, or a three-phase active power factor correction circuit.
[0036] Furthermore, if Figure 3As shown, the first filter network 32 includes a first filter capacitor C1, a first end of which is connected to the positive terminal of the DC power supply V1, and a second end of which is connected to the negative terminal of the DC power supply V1. The first switch network includes a first full-bridge switch transistor network consisting of switch transistors Q1, switch transistors Q2, switch transistors Q3, and switch transistors Q4. The control terminals of the switch transistors Q1, switch transistors Q2, switch transistors Q3, and switch transistors Q4 receive control signals, and the switch transistors Q1, switch transistors Q2, switch transistors Q3, and switch transistors Q4 are connected to each other. The first resonant network includes a first resonant capacitor Cr1 and a first resonant inductor Lr1. The first end of the first full-bridge switch tube network (the connection point of the switch tubes Q1 and Q3) is connected to the positive power supply electrode of the DC power supply V1, the second end (the connection point of the switch tubes Q2 and Q4) is connected to the negative power supply electrode of the DC power supply V1, the third end (the connection point of the switch tubes Q1 and Q3) is connected to the first end of the first resonant network (i.e., the first end of the first resonant inductor Lr1), and the fourth end (the connection point of the switch tubes Q2 and Q3) is connected to the second end of the first resonant network (i.e., the first end of the first resonant capacitor Cr1); the second end of the first resonant inductor Lr1 is connected to the first end of the primary side of the transformer T1 and the first end of the excitation inductor Lm; the second end of the first resonant capacitor Cr1 is connected to the second end of the primary side of the transformer T1.
[0037] like Figure 3 As shown, the regulating unit 21 includes a single-pole double-throw relay K1, the moving contact of the single-pole double-throw relay K1 is connected to the second end of the primary side of the transformer T1, the first static contact is connected to the second end of the excitation inductor Lm, and the second static contact is connected to the third end of the excitation inductor Lm, that is, the middle tap of the excitation inductor Lm.
[0038] Furthermore, if Figure 3As shown, the second resonant network includes a second resonant inductor Lr2 and a second resonant capacitor Cr2; the second switch network includes a second full-bridge switch network consisting of switches Q5, Q6, Q7, and Q8. The control terminals of the switches Q5, Q6, Q7, and Q8 receive control signals, and the switches Q5, Q6, Q7, and Q8 are connected to each other. The second resonant inductor Lr2 and the second resonant capacitor Cr2 are connected in series between the first terminal of the secondary side of the transformer T1 and the first terminal of the second full-bridge switch network (the connection point between switches Q5 and Q6). The second terminal of the second full-bridge switch network (the connection point between switches Q7 and Q8) is connected to the second terminal of the secondary side of the transformer T1, the third terminal (the connection point between switches Q5 and Q7) is connected to the positive power supply terminal of the DC power supply network V2, and the fourth terminal (the connection point between switches Q8 and Q6) is connected to the negative power supply terminal of the DC power supply network V2.
[0039] The switches Q1-Q8 may be any suitable switches, including but not limited to metal-oxide semiconductor field-effect transistors, insulated gate bipolar transistors, power transistors, insulated gate field-effect transistors, gate turn-off thyristors (GOTs), or thyristors. Any suitable full-bridge network of switches is applicable to the present invention.
[0040] Figure 4 yes Figure 3 The power flow diagram of the wide range and high efficiency DCDC converter working in full-bridge mode is shown. Figure 5 yes Figure 3 The power flow diagram of the wide range and high efficiency DCDC converter working in half-bridge mode is shown below. Figure 2-5 The working principle of the wide-range and high-efficiency DCDC converter of the present invention is described as follows.
[0041] In this preferred embodiment, the center-tapped excitation inductor Lm and the single-pole double-throw relay K1 form an adjustable excitation inductance module with variable magnitude. This module features a simple structure and is easily controlled. The adjustable excitation inductance module can be used to change the inductance ratio and thus the gain characteristics, thereby expanding the output voltage range within a given operating frequency range, or narrowing the operating frequency range within a given output voltage range. Furthermore, increasing the inductance of the excitation inductor Lm can reduce the excitation current, thereby reducing losses and improving efficiency. For example, in normal operation, if the required gain is less than 1, the excitation inductor Lm can be increased via relay K1 to improve DC-DC converter efficiency or achieve a lower output voltage. If the required gain is greater than 1, the excitation inductor Lm can be reduced via the single-pole double-throw relay K1 to achieve a higher load capacity or a higher output voltage.
[0042] Furthermore, in this embodiment, the first full-bridge switch network formed by switches Q1-Q4 can operate in full-bridge and half-bridge modes. In full-bridge mode, the switching logic of switches Q1-Q4 is the same as that of a typical full-bridge LLC converter. In half-bridge mode, switch Q3 is normally open, switch Q4 is normally closed, and only switches Q1 and Q2 operate as switching devices, forming a converter similar to a half-bridge LLC converter. By switching the operating mode, the gain range can be widened. When the converter requires low voltage or low power output, it can be switched to half-bridge mode to change the gain curve and reduce the converter's operating frequency to reduce losses and improve efficiency.
[0043] Furthermore, in this embodiment, a resonant capacitor and a resonant inductor are designed based on the first full-bridge switch tube network. Through the combination of a single-pole double-throw relay and a resonant inductor, and in conjunction with the switching of the half-bridge and full-bridge working modes of the first switch network, the overall efficiency of the converter can be further improved, and the input and output voltage range of the converter can be further widened.
[0044] Figure 6 This is a principle block diagram of another preferred embodiment of the wide-range and high-efficiency DCDC converter of the present utility model. Figure 7 yes Figure 6 The circuit diagram of the wide range and high efficiency DCDC converter is shown in FIG. Figure 6-7 In the preferred embodiment shown, the wide-range high-efficiency DCDC converter is a unidirectional wide-range high-efficiency DCDC converter.
[0045] exist Figure 6-7 In the preferred embodiment shown, the secondary side module 40 includes a rectifier network 45, a third filter network 46 and a load R connected in sequence. Figure 7 As shown, the rectifier network 45 includes a full-bridge rectifier network consisting of a diode D1, a diode D2, a diode D3, and a diode D4. Diodes D1, D2, D3, and D4 are connected to each other. The first end of the full-bridge rectifier network (i.e., the connection point between diodes D1 and D2) is connected to the first end of the secondary side of the transformer T1, the second end (i.e., the connection point between diodes D3 and D4) is connected to the second end of the secondary side of the transformer T1, the third end (i.e., the connection point between diodes D1 and D3) is connected to the first end of the load, and the fourth end (i.e., the connection point between diodes D2 and D4) is connected to the second end of the load R. The third filter network 46 includes a filter capacitor C2, which is also connected to both ends of the load R.
[0046] Of course, those skilled in the art will appreciate that in other preferred embodiments of the present invention, the rectifier network may also be a switch tube rectifier network, and any suitable functional module may be added to the secondary side module.
[0047] Figure 6-7The unidirectional wide range high efficiency DCDC converter shown in FIG can also achieve the beneficial effects of the present invention. Its principle is similar to that of FIG. Figure 2-3 The bidirectional wide-range high-efficiency DCDC converters shown are basically the same and will not be described again here.
[0048] The wide-range, high-efficiency DC-DC converter of the present invention utilizes an adjustable excitation inductance module to change the inductance ratio and gain characteristics. This allows the output voltage range to be expanded within a certain operating frequency range, or the operating frequency range to be narrowed within a certain output voltage range. Furthermore, increasing the excitation inductance Lm reduces the excitation current, thereby reducing losses and improving efficiency. Furthermore, the wide-range, high-efficiency DC-DC converter of the present invention is also applicable to various application scenarios, such as bidirectional or unidirectional DC-DC converters.
[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A wide range high efficiency DCDC converter, characterized in that: It includes: a transformer module, an adjustable excitation inductance module and a primary side module sequentially arranged on the primary side of the transformer module, and a secondary side module arranged on the secondary side of the transformer module; The first end of the adjustable excitation inductance module is connected to the first output end of the primary module, the second end is connected to the second output end of the primary module, the third end is connected to the first end of the primary side of the transformer module, and the fourth end is connected to the second end of the primary side of the transformer module; the first input end of the secondary side module is connected to the first end of the secondary side of the transformer module, and the second input end is connected to the second end of the secondary side of the transformer module.
2. The wide range and high efficiency DCDC converter according to claim 1, characterized in that: The adjustable excitation inductance module includes an excitation inductor and an adjustment unit, the first end of the excitation inductor is connected to the first end of the primary side of the transformer module, the second end or the third end of the excitation inductor is connected to the second end of the primary side of the transformer module via the adjustment unit; the third end of the excitation inductor is located between the first end and the second end of the excitation inductor.
3. The wide range and high efficiency DCDC converter according to claim 2, characterized in that: The regulating unit includes a single-pole double-throw relay, the moving contact of the single-pole double-throw relay is connected to the second end of the primary side of the transformer module, the first static contact is connected to the second end of the excitation inductor, and the second static contact is connected to the third end of the excitation inductor.
4. The wide range and high efficiency DCDC converter according to claim 3, characterized in that: The third end of the excitation inductor is a center tap of the excitation inductor.
5. The wide range and high efficiency DCDC converter according to any one of claims 1 to 4, characterized in that: The primary side module includes a first DC power supply network, a first filter network, a first switch network and a first resonant network which are connected in sequence.
6. The wide range and high efficiency DCDC converter according to claim 5, characterized in that: The first switch network includes a first full-bridge switch network consisting of a first switch tube, a second switch tube, a third switch tube, and a fourth switch tube, wherein a first end of the first full-bridge switch network is connected to the positive power supply of the first DC power supply network, a second end is connected to the negative power supply of the first DC power supply network, a third end is connected to the first end of the first resonant network, and a fourth end is connected to the second end of the first resonant network; The first resonant network includes a first resonant capacitor and a first resonant inductor, the first end of the first resonant inductor is connected to the third end of the first full-bridge switch tube network, and the second end is connected to the first end of the primary side of the transformer module and the first end of the excitation inductor; the first end of the first resonant capacitor is connected to the fourth end of the first full-bridge switch tube network, and the second end is connected to the second end of the primary side of the transformer module.
7. The wide range and high efficiency DCDC converter according to claim 6, characterized in that: The first filter network includes a first filter capacitor, a first end of the first filter capacitor is connected to the positive power supply of the first DC power supply network, and a second end of the first filter capacitor is connected to the negative power supply of the first DC power supply network.
8. The wide range and high efficiency DCDC converter according to claim 5, characterized in that: The secondary side module includes a second resonant network, a second switch network, a second filter network and a second DC power supply network which are connected in sequence.
9. The wide range and high efficiency DCDC converter according to claim 8, characterized in that: The second resonant network includes a second resonant inductor and a second resonant capacitor; the second switch network includes a second full-bridge switch tube network consisting of a fifth switch tube, a sixth switch tube, a seventh switch tube and an eighth switch tube; the second resonant inductor and the second resonant capacitor are connected in series between the first end of the secondary side of the transformer module and the first end of the second full-bridge switch tube network, the second end of the second full-bridge switch tube network is connected to the second end of the secondary side of the transformer module, the third end is connected to the positive power supply of the second DC power supply network, and the fourth end is connected to the negative power supply of the second DC power supply network.
10. The wide range and high efficiency DCDC converter according to claim 5, characterized in that: The secondary side module includes a rectifier network, a third filter network and a load connected in sequence; the rectifier network includes a full-bridge rectifier network composed of a first diode, a second diode, a third diode and a fourth diode, the first end of the full-bridge rectifier network is connected to the first end of the secondary side of the transformer module, the second end is connected to the second end of the secondary side of the transformer module, the third end is connected to the first end of the load, and the fourth end is connected to the second end of the load.