Small module high-voltage isolation circuit
By adopting a wide-body isolation module in the BMS product, integrating two independent transformer channels and enhancing the creepage distance, the problems of creepage distance and space occupation under high-voltage platforms are solved, achieving effective high-voltage isolation and space saving.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2026-04-07
AI Technical Summary
Existing technologies struggle to meet creepage distance requirements under high-voltage platforms, and the isolation modules occupy significant space, making PCB design for BMS products difficult.
It adopts a wide-body isolation module, which contains two independent transformer channels. The creepage distance requirements are met by increasing the transformer size, and the isolation processing of power supply and daisy chain signals is integrated. An internal metal shielding layer is set to enhance the isolation effect.
It achieves creepage requirements on a 1500V platform while saving PCB layout space and reducing the area occupied by the isolation module.
Smart Images
Figure CN224097704U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to high voltage isolation circuit technical field especially a small module high voltage isolation circuit. BACKGROUND
[0002] At present, BMS scheme integrates high voltage detection function, so high voltage and low voltage modules exist on the PCB board simultaneously, low voltage module needs a daisy chain signal for communication between high voltage chip and low voltage MCU in addition to providing power supply for high voltage module, so the module circuit of isolation has two, respectively isolation power supply and isolation daisy chain communication.
[0003] At present, the highest electrical architecture of new energy passenger car is 800V platform, isolation power supply and isolation daisy chain communication use two small package transformers to do isolation communication respectively, this scheme can just meet the creepage distance requirement of 800V platform, but it is difficult to meet the higher voltage platform. In addition, the isolation scheme using two transformers will cause the isolation module to occupy the relatively large space on BMS PCB.
[0004] With the development of new energy industrial automobile 1500V, BMS design has higher requirements for high voltage isolation. In order to meet the creepage distance requirement of higher voltage safety, the power isolation and signal isolation module also need to be further increased, which will bring difficulty to the PCB design of BMS product. SUMMARY
[0005] The purpose of this section is to outline some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments, which may be simplified or omitted in this section, the abstract of the specification and the utility model name to avoid obscuring the purpose of this section, the abstract of the specification and the utility model name, and such simplification or omission cannot be used to limit the scope of the utility model.
[0006] In view of the above and / or existing problems in the prior art, the utility model is proposed.
[0007] Therefore, the technical problem to be solved by the utility model is small creepage distance and the isolation module will occupy relatively large space.
[0008] To solve the above technical problems, the utility model provides technical scheme as follows: A small module high voltage isolation circuit, including, wide body isolation module, its inside at least including first transformer channel and second transformer channel, transformer drive circuit, its output and first transformer channel are connected through pin TD+1, TD-3, CT2 corresponding connection for providing high voltage drive signal or excitation signal to first transformer channel, isoSPI interface, with left pin RD+4, CT5, RD-6 of second transformer channel corresponding connection for isoSPI communication signal input or output to wide body isolation module, monitoring circuit, with right pin 9RX+, 8CT, 7RX- of second transformer channel corresponding connection for receiving and processing communication signal from isoSPI interface through wide body isolation module isolation, right pin 12TX+, 11CT, 10TX- of first transformer channel are connected with monitoring circuit, for providing high voltage drive or auxiliary power to monitoring circuit, and can monitor this high voltage side signal.
[0009] As a preferred scheme of the small module high voltage isolation circuit of the utility model, wherein: the minimum creepage distance between the first transformer channel and the second transformer channel between the primary side and the secondary side is not less than 15mm.
[0010] As a preferred scheme of the small module high voltage isolation circuit of the utility model, wherein: the transformer drive circuit includes pulse width modulation generation module and level conversion module, for converting external power supply or signal into the waveform suitable for the driving of the primary side of the first transformer channel and inputting into the wide body isolation module through the pin TD+1, TD-3.
[0011] As a preferred scheme of the small module high voltage isolation circuit of the utility model, wherein: the isoSPI interface and the left pin RD+4, RD-6 of the second transformer channel are provided with EMI filter or impedance matching network.
[0012] As a preferred scheme of the small module high voltage isolation circuit of the utility model, wherein: the monitoring circuit includes analog-to-digital converter or special communication transceiver, for collecting and processing the high voltage drive or power supply signal output by the right pin 12TX+, 10TX- of the first transformer channel and the isoSPI signal output by the right pin 9RX+, 7RX- of the second transformer channel respectively.
[0013] As a preferred scheme of the small module high voltage isolation circuit of the utility model, wherein: when the right pin 11CT of the first transformer channel is connected with the monitoring circuit, signal coupling capacitor, current limiting resistor or other protection elements can be additionally arranged between the pin and the monitoring circuit.
[0014] As a preferred scheme of the small module high-voltage isolation circuit, the wide-body isolation module is further provided with a metal shielding layer or a ground reference layer between the first transformer channel and the second transformer channel.
[0015] The utility model discloses the beneficial effect: through increasing transformer appearance size meets the requirement of creeping distance. Simultaneously, two independent channels are integrated inside, and the isolation processing is adopted between the channel, so can connect power supply and daisy chain signal simultaneously. Compared with two independent layout modules, this scheme not only can satisfy 1500V creeping requirement, but also can save the PCB layout space of original 1 / 3. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the following will be briefly introduced to the drawing needed to be used in the embodiment description, obviously, the drawing in the following description is only some embodiments of the utility model, for the ordinary skilled person in the art, under the premise of not paying the creative labor, still can obtain other drawings according to these drawings. Wherein:
[0017] Figure 1 It is the circuit diagram of small module high-voltage isolation circuit. DETAILED DESCRIPTION
[0018] In order to make the above-mentioned purpose, features and advantages of the utility model more obvious and easy to understand, the specific implementation of the utility model will be described in detail below combining with the drawings of the specification.
[0019] In the following description, a lot of specific details are set forth in order to fully understand the utility model, but the utility model can also be implemented in other ways different from the description, and the skilled person in the art can make similar generalization without violating the connotation of the utility model, therefore, the utility model is not limited by the specific embodiments disclosed below.
[0020] Secondly, the utility model is described in detail in combination with the schematic diagram, when the embodiment of the utility model is described in detail, for the convenience of explanation, the section view of the device structure will be partially enlarged without general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the utility model here. In addition, the three-dimensional spatial dimension of length, width and depth should be contained in actual manufacture.
[0021] Thirdly, the "one embodiment" or "embodiment" referred to here means that the specific features, structures or characteristics can be included in at least one implementation of the utility model. In this specification, "in one embodiment" does not mean the same embodiment, nor is it an independent or alternative embodiment that excludes other embodiments.
[0022] Embodiment 1
[0023] Referring to Figure 1 The embodiment provides a small-module high-voltage isolation circuit, which comprises a wide-body isolation module 100, a transformer driving circuit 110, an isoSPI interface 120 and a monitoring circuit 130.
[0024] Specifically, the wide-body isolation module 100 internally comprises at least a first transformer channel 210 and a second transformer channel 220. The first transformer channel 210 has a transformation ratio of 1:1.5, and its primary side pins comprise TD+1, CT2 and TD-3, and its secondary side pins comprise 12TX+, 11CT and 10TX-. The second transformer channel 220 has a transformation ratio of 1:1, and its primary side pins comprise RD+4, CT5 and RD-6, and its secondary side pins comprise 9RX+, 8CT and 7RX-.
[0025] The first transformer channel 210 is used for high-voltage driving / power supply isolation, and the second transformer channel 220 is used for isoSPI communication signal isolation. The shell is made of high-voltage-resistant insulating material and is designed by a winding process of increasing the creepage distance, and the creepage distance between the primary side and the secondary side is greater than or equal to 15 mm, so as to meet the creepage distance requirement of a 1500V system.
[0026] The transformer driving circuit 110 is connected to the first transformer channel 210 through the pins TD+1, TD-3 and CT2, and is used for providing a high-voltage driving signal or an excitation signal to the first transformer channel 210. The transformer driving circuit 110 internally comprises a PWM generation and level conversion module, which is used for converting an external power supply or signal into a waveform suitable for driving the primary side of the first transformer channel 210 and inputting the waveform into the wide-body isolation module 100 through the pins TD+1 and TD-3. CT2 can be used for auxiliary control or synchronization signal and is connected to the primary side of the transformer through appropriate impedance matching or coupling capacitors.
[0027] The isoSPI interface 120 is connected to the left pins RD+4, CT5 and RD-6 of the second transformer channel 220, and is used for inputting or outputting an isoSPI communication signal to the wide-body isolation module 100. If necessary, an EMI filter or an impedance matching device can be added between RD+4 and RD-6, so as to suppress high-frequency noise and ensure communication quality.
[0028] The monitoring circuit 130 is connected with the right pins 9RX+, 8CT, 7RX- of the second transformer channel 220, for receiving and processing the communication signals isolated from the isoSPI interface 120 through the wide-body isolation module 100; the right pins 12TX+, 11CT, 10TX- of the first transformer channel 210 are connected with the monitoring circuit 130, for providing high-voltage driving or auxiliary power supply to the monitoring circuit 130, and being able to monitor the high-voltage side signals, such as detecting the output level of the high-voltage driving side, monitoring the isoSPI communication data, etc.; the internal part can contain an analog-digital conversion module or a special communication transceiver, for collecting and processing the high-voltage driving or power supply signals output from the right pins 12TX+, 10TX- of the first transformer channel 210 and the isoSPI signals output from the right pins 9RX+, 7RX- of the second transformer channel 220, respectively.
[0029] Further, when the right pin 11CT of the first transformer channel 210 is connected with the monitoring circuit 130 or the related detection / power supply unit thereof, a signal coupling capacitor, a current limiting resistor or other protection elements can be additionally arranged between the pin and the monitoring circuit 130, to realize necessary noise filtering, voltage clamping or safety isolation.
[0030] Further, the wide-body isolation module 100 is further provided with a metal shielding layer or a ground reference layer between the first transformer channel 210 and the second transformer channel 220.
[0031] When the transformer driving circuit 110 works, the excitation waveform is applied to the primary winding of the first transformer channel 210 through TD+1 and TD-3, and the corresponding high-voltage driving monitoring signals are output from the pins 12TX+, 10TX- of the secondary side after transformer coupling.
[0032] The isoSPI interface 120 provides communication data to the RD+4 and RD-6 of the primary side of the second transformer channel 220, and the high-voltage monitoring circuit 130 is output from the pins 9RX+ and 7RX- of the secondary side of the second transformer channel 220 after coupling, so as to realize the safety isolation of the daisy chain communication.
[0033] The two channels are completely independent internally, and have a creepage distance ≥15mm between the primary side and the secondary side of each channel, which ensures the high-voltage safety under the platform of 1500V.
[0034] Compared with using two independent transformers, the single wide-body isolation module 100 can not only meet the high-voltage insulation requirements, but also significantly save the PCB space.
[0035] The circuit, by increasing the transformer appearance size satisfies the creepage distance requirement, simultaneously internally integrated two independent channels, adopts isolation processing between the channels, therefore can simultaneously connect the power supply and the daisy chain signal, compared with two independent layout modules, this scheme not only can satisfy 1500V creepage requirement, but also can save the original 1 / 3 PCB layout space.
[0036] Importantly, it should be noted that the constructions and arrangements of the present application shown in the various exemplary embodiments are by way of illustration only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described in the application. For example, elements shown as integrally formed can be constructed of multiple parts or elements, the position of elements can be reversed or otherwise varied, and the nature or number of elements or positions can be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present application. The order or sequence of any process or method steps can be varied or re-sequenced without materially affecting the application. Any "means plus function" clauses are intended to cover the structures described herein as performing the recited functionality and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions, and arrangement of the exemplary embodiments without departing from the scope of the present application. Accordingly, the present application is not limited to the particular embodiments described and illustrated herein, but extends to equivalents of which the foregoing describes are intended to cover.
[0037] Furthermore, in an effort to provide a concise description of exemplary embodiments, all features of an actual implementation can not be described (i.e., those unrelated to the best mode of practicing the present application, or those unrelated to enabling the claimed application).
[0038] It should be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions can be made. Such development efforts might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
[0039] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.
Claims
1. A small-module high-voltage isolation circuit, characterized in that: The wide-body isolation module (100) includes at least a first transformer channel (210) and a second transformer channel (220) inside; The transformer drive circuit (110) has its output terminal connected to the first transformer channel (210) via pins TD+1, TD-3, and CT2, and is used to provide a high-voltage drive signal or excitation signal to the first transformer channel (210). The isoSPI interface (120) is connected to the left pins RD+4, CT5, and RD-6 of the second transformer channel (220) and is used to input or output isoSPI communication signals to the wide-body isolation module (100). The monitoring circuit (130) is connected to the right pins 9RX+, 8CT, and 7RX- of the second transformer channel (220) to receive and process the communication signal isolated from the isoSPI interface (120) by the wide-body isolation module (100); the right pins 12TX+, 11CT, and 10TX- of the first transformer channel (210) are connected to the monitoring circuit (130) to provide high-voltage drive or auxiliary power to the monitoring circuit (130) and to monitor the high-voltage side signal.
2. The small module high-voltage isolation circuit according to claim 1, characterized in that: The minimum creepage distance between the primary and secondary sides of the first transformer channel (210) and the second transformer channel (220) is not less than 15mm.
3. The small module high-voltage isolation circuit according to claim 1 or 2, characterized in that: The transformer drive circuit (110) includes a pulse width modulation generation module and a level conversion module, which are used to convert external power supply or signal into waveforms suitable for primary-side driving of the first transformer channel (210) and input them to the wide-body isolation module (100) through pins TD+1 and TD-3.
4. The small module high-voltage isolation circuit according to claim 3, characterized in that: An EMI filter or impedance matching network is provided between the isoSPI interface (120) and the left pins RD+4 and RD-6 of the second transformer channel (220).
5. The small module high-voltage isolation circuit according to claim 4, characterized in that: The monitoring circuit (130) includes an analog-to-digital converter or a dedicated communication transceiver, used to acquire and process the high-voltage drive or power supply signals output from the right pins 12TX+ and 10TX- of the first transformer channel (210) and the isoSPI signals output from the right pins 9RX+ and 7RX- of the second transformer channel (220).
6. The small module high-voltage isolation circuit according to claim 5, characterized in that: When the right pin 11CT of the first transformer channel (210) is connected to the monitoring circuit (130), a signal coupling capacitor, current limiting resistor or other protection components can be added between the pin and the monitoring circuit (130).
7. The small module high-voltage isolation circuit according to any one of claims 4 to 6, characterized in that: The wide-body isolation module (100) is further provided with a metal shielding layer or a ground reference layer between the first transformer channel (210) and the second transformer channel (220).