Power converter PCB layout structure

Abstract

The invention discloses a PCB layout structure of a power converter. The PCB layout structure sequentially comprises a signal board, a driving board and a power board from top to bottom, each daughter board comprises an interface used for being connected with other daughter boards; wherein the signal board is used for sampling the output of the power board and outputting a control signal, and signal wires are arranged in the top layer and the bottom layer of the signal board; the driving board comprises a driving circuit used for generating a driving signal in response to a control signal, a signal wire is arranged in the top layer of the driving board, and an auxiliary power supply wire and a signal ground are arranged in the bottom layer of the driving board; the power loop in the power board comprises a power switch device which is used for responding to a driving signal to execute on-off actions so as to realize power conversion, the driving board is arranged right above the power switch device, and power wires are arranged in the top layer and the bottom layer of the power board. According to the invention, circuit decoupling is realized, and the driving circuit is prevented from being influenced by electromagnetic radiation generated by a power switch device area.

Description

Technical Field

[0001] The present invention relates to the field of power electronics wiring, and in particular to a layout structure of a power converter PCB board. Background Art

[0002] In the hardware design of power electronic systems, PCB wiring not only concerns the realization of circuit functions, but also directly affects the performance, reliability, and safety of the system. For existing power converter PCB boards, a multi-layer PCB wiring scheme is adopted for layout. Usually, power-stage circuits such as pre-charge circuits, DC filter circuits, power switch devices, AC filter circuits, voltage and current sensors, and signal-stage circuits such as sampling protection circuits, control circuits, drive circuits, and auxiliary power supplies included in the entire system are wired on a single PCB board. The wiring of each part of the circuit is intricate and deeply coupled, resulting in the number of PCB layers reaching six or eight layers.

[0003] However, for the power circuit topology of a T-type three-level four-arm bridge, a six-layer or eight-layer PCB board wiring scheme is usually adopted, with relatively high design and processing costs. Moreover, since all circuits are placed on a single PCB board, there are significant differences between signal wiring and power wiring in terms of technology. Designers need to possess the design capabilities of both, which places high requirements on designers, is not conducive to multi-person collaborative division of labor, has low development efficiency, and relatively high later maintenance costs. If a key device is damaged, the entire PCB board needs to be replaced. Additionally, during PCB layout, it is usually required that the drive circuit and the power switch device be as close as possible, but the two often occupy a large area, which makes the control circuit far from the drive circuit and the sampling circuit far from each sensor. The electromagnetic radiation generated in the area of the power switch device with rapidly changing high voltage and large current is relatively strong, causing relatively large interference to the signal paths of the signal loop, especially the drive circuit and the sampling circuit, and easily leading to problems such as signal mis-triggering and sampling signal distortion in the signal loop, reducing the reliability and stability of the product; even if a signal ground layer is added between the power layer and the signal layer of the PCB board as a shielding layer, the electromagnetic shielding effect is also very limited. And since the drive circuit and the power switch device are directly connected on the schematic diagram, the drive circuit is usually placed next to the power switch device on the PCB board. In addition to electromagnetic interference problems, the long-term high-temperature environment near the power device also has a great impact on the lifespan of the drive chip. Even under certain special working conditions, the temperature exceeds the rated operating temperature of the drive chip, causing the chip to malfunction. Summary of the Invention

[0004] An embodiment of the present invention provides a layout structure of a power converter PCB board, which realizes the decoupling of the circuit and avoids the influence of electromagnetic radiation generated in the area of the power switch device on the drive circuit, ensuring the long-term stable operation of the power converter.

[0005] To solve the above technical problems, an embodiment of the present invention provides a PCB board layout structure for a power converter, including: three PCB sub-boards, namely a signal board, a drive board, and a power board, arranged from top to bottom in sequence; each PCB sub-board includes an interface for connecting to other PCB sub-boards;

[0006] Among them, the signal board is used to sample the output of the power board and output a corresponding control signal, and signal traces are arranged in both the top layer and the bottom layer of the signal board;

[0007] The drive board includes a drive circuit for generating and outputting a drive signal in response to the control signal. Signal traces are arranged in the top layer of the drive board, and auxiliary power traces and signal ground are arranged in the bottom layer of the drive board;

[0008] The power board includes a power loop, and the power loop includes a power switch device for performing on-off actions in response to the drive signal to achieve power conversion. Power traces are arranged in both the top layer and the bottom layer of the power board, and the drive board is placed directly above the power switch device.

[0009] Implementing the embodiment of the present invention, the PCB board layout structure of the power converter includes a signal board, a driver board, and a power board from top to bottom in sequence. And in the bottom layer of the driver board, there are arranged auxiliary power traces and signal ground, using the signal ground as a shielding layer to avoid the influence of electromagnetic radiation generated in the power switch device area on the signal loop, especially the drive circuit. Among them, the signal board is used to sample the output of the power board and output corresponding control signals. Signal traces are arranged in both the top layer and the bottom layer of the signal board to ensure low latency and low noise in signal transmission. The driver board includes a drive circuit for generating and outputting drive signals in response to the control signals. Signal traces are arranged in the top layer of the driver board, and auxiliary power traces and signal ground are arranged in the bottom layer of the driver board, which helps to reduce signal interference and improve the stability of the drive signals. As for the power board, power traces are arranged in both the top layer and the bottom layer, and the power switch devices in the power loop can directly respond to the drive signals to perform on-off actions, optimizing the power conversion process and improving the working efficiency of the power converter. In addition, placing the driver board directly above the power switch devices in the power board can reduce the transmission path length of the drive signals, reduce signal loss and interference. This tightly coupled design helps to improve the response speed and switching efficiency of the power switch devices, thereby enhancing the efficiency of the entire power converter. Further, the entire system is designed modularly according to functions, only retaining the connection points of each sub-module, and decoupling all the remaining circuits. That is, the signal board, the driver board, and the power board are connected through interfaces, separating the signal loop and the power loop, reducing the electromagnetic interference that may be generated during the power conversion process. And the drive chip in the driver board can be isolated from the long-term high-temperature environment where the power switch devices are located, ensuring the long-term stable operation of the drive chip. Except for the interfaces of each PCB sub-board, the remaining circuits are completely decoupled and do not interfere with each other. This can not only facilitate collaborative development by multiple people and improve efficiency, but also only require replacing the corresponding PCB sub-board when upgrading or replacing a certain part, without having to redesign the entire system, so as to reduce the maintenance cost.

[0010] As a preferred solution, in the top layer of the signal board, there are arranged a first preset number of signal traces, a second preset number of auxiliary power traces and signal ground, a sampling circuit, and a control circuit. In the bottom layer of the signal board, there are arranged a third preset number of auxiliary power traces and signal ground, a fourth preset number of signal traces, and an auxiliary power supply for powering the signal board and the driver board;

[0011] Wherein, the first preset quantity is greater than the second preset quantity, and the third preset quantity is greater than the fourth preset quantity; the sampling circuit is configured to perform real-time sampling on the voltage signal or current signal output by the power board and output a sampling signal; the control circuit is configured to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the driving board.

[0012] In a preferred embodiment of the present invention, auxiliary power traces and signal grounds are arranged on both the top layer and the bottom layer of the signal board, and the number of signal traces is significantly more than that of the auxiliary power traces. This design separates the auxiliary power from the signal traces, optimizes the transmission paths of signals and electrical energy, reduces power loss and heat generation, improves the energy efficiency of the signal board, ensures the priority of the main signal transmission path, reduces the interference of power supply noise on signal transmission, and ensures the stability of control signals and sampling signals. In addition, the sampling circuit and the control circuit on the signal board are independently arranged on the top layer and the bottom layer respectively, which is convenient for debugging and maintenance.

[0013] As a preferred solution, between the top layer and the bottom layer of the signal board, there is also an auxiliary power layer and an auxiliary power ground layer;

[0014] Wherein, the auxiliary power layer is provided with auxiliary power traces and an auxiliary power source for supplying power to the signal board and the driving board;

[0015] The auxiliary power ground layer is provided with a signal ground.

[0016] In a preferred embodiment of the present invention, if the circuit complexity is slightly higher, an auxiliary power layer and an auxiliary power ground layer can be added between the top layer and the bottom layer of the signal board to form a four-layer PCB board wiring solution for the signal board. And the auxiliary power layer is completely independent of the signal traces and power traces, avoiding the interference of power fluctuations on the signal and power circuits. The auxiliary power ground layer provides a dedicated signal ground plane, which can effectively isolate the signal ground from the power ground, significantly reduce the ground loop noise, and avoid the influence of the power loop on the signal, so as to further improve the stability and reliability of the system.

[0017] As a preferred solution, the PCB board layout structure of a power converter further includes:

[0018] The sampling circuit is arranged in the top layer of the signal board, and the control circuit is arranged in the bottom layer of the signal board;

[0019] Or, the control circuit is arranged in the top layer of the signal board, and the sampling circuit is arranged in the bottom layer of the signal board;

[0020] Among them, the sampling circuit is used to sample the voltage signal or current signal output by the power board in real time and output a sampling signal; the control circuit is used to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the drive board.

[0021] Implementing the preferred solution of the embodiment of the present invention, arranging the sampling circuit and the control circuit on different layers to achieve the separated layout of the sampling circuit and the control circuit can better manage signal traces, reduce crosstalk and electromagnetic interference. Moreover, the sampling circuit is a sensitive component. By separating the layout of the control circuit and the sampling circuit, the heat generated by the control circuit will not directly affect the accuracy of the sampling circuit, ensuring the stable operation of the system.

[0022] As a preferred solution, the power loop further includes: a voltage-current sensor;

[0023] Among them, the voltage-current sensor is used to detect the voltage or current flowing through the power loop, perform conversion processing on the detected voltage or current, and then transmit the converted signal to the signal board.

[0024] Implementing the preferred solution of the embodiment of the present invention, through the voltage-current sensor, the large voltage and large current in the power loop are converted into small voltage and small current, which is convenient for output to the signal board for processing. Moreover, the introduction of the voltage-current sensor realizes the closed-loop control of the power loop. The signal board dynamically adjusts the control signal according to the real-time data fed back by the sensor to ensure that the working state of the power converter always remains within the optimized range.

[0025] As a preferred solution, the power loop further includes: a pre-charge circuit and a DC filter circuit connected in series in the power loop;

[0026] Among them, the pre-charge circuit includes a pre-charge resistor and a bypass relay connected in parallel with the pre-charge resistor;

[0027] The pre-charge circuit is connected to the output interface of the signal board;

[0028] The DC filter circuit is connected in series with the pre-charge circuit and is used to filter the signal output by the pre-charge circuit to filter out the voltage harmonics on the DC side and transmit the processed signal to the power switching device.

[0029] Implementing the preferred solution of the embodiments of the present invention, the bypass relay is connected in parallel with the pre-charge resistor. When the capacitor in the DC filter circuit is fully charged, the control signal output by the signal board is used to close the bypass relay connected in parallel with the pre-charge resistor, so that the pre-charge resistor in the pre-charge circuit is short-circuited, and the current in the power loop flows through the bypass relay, preventing the voltage of the capacitor (i.e., the bus capacitor) in the DC filter circuit from overshooting and the current from being too large at the moment of power-on, thereby damaging the capacitor and further extending the service life of the components. In addition, during the switching process of the power switch device, the DC bus voltage will produce large fluctuations. Therefore, the DC filter circuit is used to filter out the voltage harmonics on the DC side to stabilize the DC bus voltage, ensure that the DC signal input to the power switch device is smooth and stable, and reduce the interference to the power switch device.

[0030] As a preferred solution, the power loop further includes: an AC filter circuit;

[0031] Among them, the AC filter circuit is connected in series with the power switch device and is used to filter the signal output by the power switch device to filter out the high-frequency voltage and current harmonics on the AC side and transmit the processed signal to the voltage and current sensor.

[0032] Implementing the preferred solution of the embodiments of the present invention, using the AC filter circuit to filter out the high-frequency voltage and current harmonics on the AC side can obtain stable AC voltage and current, reduce the influence of high-frequency harmonics on the load, ensure that the load can absorb energy more efficiently, and further improve the energy utilization rate of the system.

[0033] As a preferred solution, a fifth preset number of power traces and a sixth preset number of signal traces are arranged in the top layer of the power board, and a seventh preset number of power traces, an eighth preset number of signal traces and a signal ground are arranged in the bottom layer of the power board;

[0034] Among them, the fifth preset number is greater than the sixth preset number, and the seventh preset number is greater than the eighth preset number.

[0035] Implementing the preferred solution of the embodiments of the present invention, arranging more power traces in the top and bottom layers of the power board, which is a PCB sub-board, can more effectively manage the current distribution in the power loop, reduce the trace impedance and power loss, which helps to improve the efficiency of the power converter, reduce heat generation, and thus improve the reliability of the system.

[0036] As a preferred solution, between the top layer and the bottom layer of the power board, there are also an auxiliary power supply layer and an auxiliary power supply ground layer;

[0037] Among them, a fifth preset number of power traces are arranged in the top layer of the power board, a seventh preset number of power traces are arranged in the bottom layer of the power board, a sixth preset number of signal traces and power traces are arranged in the auxiliary power supply layer, and an eighth preset number of signal traces, power traces and signal ground are arranged in the auxiliary power supply ground layer;

[0038] The fifth preset number is greater than the sixth preset number, and the seventh preset number is greater than the eighth preset number.

[0039] Implementing the preferred solution of the embodiment of the present invention, if the circuit complexity is slightly higher, an auxiliary power supply layer and an auxiliary power supply ground layer can be added between the top layer and the bottom layer of the power board to form a four-layer PCB board wiring solution for the power board. Moreover, the power traces are arranged on the top layer and the bottom layer, while the signal traces and the signal ground are arranged on the auxiliary power supply layer and the auxiliary power supply ground layer to achieve physical isolation between the power loop and the signal loop. This isolation reduces the electromagnetic interference of the power traces on the signal traces, thereby improving the electromagnetic compatibility of the system. In addition, not only are power traces arranged on the top layer and the bottom layer of the power board, but also power traces are arranged on the auxiliary power supply layer and the auxiliary power supply ground layer of the power board, which can increase the current-carrying capacity of the PCB board. Moreover, arranging more power traces on the top layer and the bottom layer helps to reduce the trace impedance of the power loop and reduce the power loss during current flow.

[0040] As a preferred solution, auxiliary power supply traces and signal ground are also arranged in the top layer of the drive board, and the number of auxiliary power supply traces and signal ground in the top layer of the drive board is less than the number of signal traces in the top layer of the drive board; signal traces are also arranged in the bottom layer of the drive board, and the number of signal traces in the bottom layer of the drive board is less than the number of auxiliary power supply traces and signal ground in the bottom layer of the drive board.

[0041] Implementing the preferred solution of the embodiment of the present invention, the bottom-layer auxiliary power supply traces carry a relatively high current. Therefore, arranging more auxiliary power supply traces and signal ground helps to evenly distribute the heat in the bottom layer and improve the heat dissipation performance. The top-layer signal traces mainly transmit low-current signals and generate less heat, so arranging more signal traces further optimizes the heat dissipation design. Description of the Drawings

[0042] Figure 1 : is a schematic flow chart of a PCB board layout structure of a power converter provided in Embodiment 1 of the present invention;

[0043] Figure 2 : is a side view of the wiring structure of the signal board in a PCB board layout structure of a power converter provided in Embodiment 1 of the present invention;

[0044] Figure 3: A side view of the wiring structure of the drive board in the PCB board layout structure of the power converter provided in the first embodiment of the present invention;

[0045] Figure 4 : A side view of the wiring structure of the power board in the PCB board layout structure of the power converter provided in the first embodiment of the present invention. Detailed implementation manners

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] It should be noted that when routing on the PCB layout, it is generally required that the drive circuit be as close as possible to the power switch device. However, if the distance is too close, the drive circuit will be severely affected by the electromagnetic radiation in the area of the power switch device. Based on this consideration, through in-depth analysis of the circuit functions and connection methods of the entire system, a modular design method is adopted. According to the function division, the system is split into three sub-boards: a signal board, a drive board, and a power board. Each sub-board retains the connection ports to other sub-boards. When designing different sub-boards, except for the connection ports, the remaining circuits are completely decoupled and do not interfere with each other. In the embodiments of the present invention, the following two layout structures are proposed for illustration.

[0048] Embodiment 1:

[0049] Please refer to Figure 1 , a PCB board layout structure of the power converter provided in the embodiment of the present invention, which includes: three PCB sub-boards, namely a signal board, a drive board, and a power board from top to bottom in sequence; each PCB sub-board includes an interface for connecting to other PCB sub-boards.

[0050] In this embodiment, the power converter includes a signal loop and a power loop. Among them, the signal loop includes a control circuit, a sampling circuit, a driving circuit, and an auxiliary power supply, with a voltage within 24V and a current within 100mA; the power loop includes a pre-charge circuit, a DC filtering circuit, a power switching device, an AC filtering circuit, a voltage and current sensor, with a voltage around 800V and a maximum current reaching 100A. In the signal loop, the auxiliary power supply provides working voltages of 24V, 12V, 5V, and 3.3V to power the chips or sensor devices in each part of the circuit; the sampling circuit is connected to the voltage and current sensors in the power loop, processes the voltage and current signals, and then gives them to the control circuit; the control circuit controls the pre-charge circuit at the initial stage of product operation, and during continuous product operation, it adjusts the control strategy in real time according to the received voltage and current signals, and transmits the control signal to the driving circuit; the driving circuit forms a driving signal with a certain driving ability after a series of level conversions on the control signal, and then gives it to the power switching device, enabling the switching device to perform continuous and high-speed on-off actions, thereby realizing the power conversion function of the entire product. Specifically, the control signal is a signal of dozens of microamps and cannot cause the switching device to act, and the driving signal is a signal of -4V / +15V. When it is -4V, the power device generates a turn-off action, and when it is +15V, the power device generates a turn-on action. Among them, the switching frequency of the power switching device is 50kHz, that is, the interval between on and off is about 20us.

[0051] Among them, the signal board is used to sample the output of the power board and output corresponding control signals. Please refer to Figure 2 (a) of. Signal traces are arranged in both the top layer (i.e., the first signal layer) and the bottom layer (i.e., the last signal layer) of the signal board.

[0052] In this embodiment, please refer to Figure 1 . The signal board contains a sampling circuit, a control circuit, and an auxiliary power supply. The signal board has control signal, sensor signal, and power interfaces connected to the power board, as well as a control signal interface connected to the driving board; the driving board only has the driving circuit part, with a control signal interface connected to the signal board and a driving signal interface connected to the power board; the power board only contains all the power loops, with the aforementioned interfaces connected to the signal board and the driving board.

[0053] As a preferred solution, please refer to Figure 2 (a) of. The top layer of the signal board is arranged with a first preset number of signal traces, a second preset number of auxiliary power supply traces, signal ground, a sampling circuit, and a control circuit. The bottom layer of the signal board is arranged with a third preset number of auxiliary power supply traces and signal ground, a fourth preset number of signal traces, and an auxiliary power supply for powering the signal board and the driving board, constituting a two-layer PCB board wiring solution for the signal board, which is applicable to the case of slightly lower circuit complexity.

[0054] Among them, the first preset quantity is greater than the second preset quantity, and the third preset quantity is greater than the fourth preset quantity. That is, within the top layer of the signal board, signal traces are mainly arranged, and a small number of auxiliary power traces and signal grounds are also arranged; while within the bottom layer of the signal board, auxiliary power traces and signal grounds are mainly arranged, and a small number of signal traces are also arranged. A sampling circuit is used to perform real-time sampling on the voltage signal or current signal output by the power board and output a sampling signal. A control circuit is used to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the drive board.

[0055] Among them, please refer to Figure 1 , the drive board includes a drive circuit for generating and outputting a drive signal in response to the control signal. Signal traces are arranged within the top layer of the drive board. Please refer to Figure 3 , auxiliary power traces and signal grounds are arranged within the bottom layer of the drive board.

[0056] As a preferred solution, please refer to Figure 3 , auxiliary power traces and signal grounds are also arranged within the top layer of the drive board, and the number of auxiliary power traces and signal grounds within the top layer of the drive board is less than the number of signal traces within the top layer of the drive board; signal traces are also arranged within the bottom layer of the drive board, and the number of signal traces within the bottom layer of the drive board is less than the number of auxiliary power traces and signal grounds within the bottom layer of the drive board. That is, within the top layer of the drive board, signal traces are mainly arranged, and a small number of auxiliary power traces and signal grounds are also arranged; while within the bottom layer of the drive board, auxiliary power traces and signal grounds are mainly arranged, and a small number of signal traces are also arranged.

[0057] Among them, please refer to Figure 1 , the power board includes a power circuit. The power circuit includes power switching devices for performing on-off actions in response to the drive signal to achieve power conversion. Power traces are arranged within both the top layer (i.e., the first signal layer) and the bottom layer (i.e., the last signal layer) of the power board. Please refer to Figure 1 , the drive board is placed directly above the power switching device.

[0058] As a preferred solution, the top layer of the power board is arranged with a fifth preset quantity of power traces and a sixth preset quantity of signal traces, and the bottom layer of the power board is arranged with a seventh preset quantity of power traces, as well as an eighth preset quantity of signal traces and signal grounds, constituting a two-layer PCB board wiring solution for the power board, which is applicable to the case of slightly lower circuit complexity.

[0059] Among them, the fifth preset quantity is greater than the sixth preset quantity, and the seventh preset quantity is greater than the eighth preset quantity.

[0060] In this embodiment, the power board is generally relatively large and is often fixed on the product chassis. The drive board is smaller in size and has a strong correlation with the power switch device area on the power board. The drive board can be vertically inserted above the power switch area by using the hard connection method of pin-header. The signal board is of medium size and can be supported on the power board or fixed on the upper chassis of the chassis. There may be multiple connections between the signal board, the drive board, and the power board, and multiple flexible flat cables can be used for connection. When necessary, a shielding layer can be wrapped to reduce interference.

[0061] As a preferred solution, please refer to Figure 1 , the power circuit further includes: a voltage-current sensor;

[0062] Among them, the voltage-current sensor is used to detect the voltage or current flowing through the power circuit, convert the detected voltage or current, and then transmit the converted signal to the signal board.

[0063] As a preferred solution, please refer to Figure 1 , the power circuit further includes: a pre-charge circuit and a DC filter circuit connected in series in the power circuit.

[0064] Among them, the pre-charge circuit includes a pre-charge resistor and a bypass relay connected in parallel with the pre-charge resistor.

[0065] The pre-charge circuit is connected to the output interface of the signal board.

[0066] The pre-charge circuit is used to short-circuit the pre-charge resistor when receiving the control signal output by the signal board.

[0067] Please refer to Figure 1 , the DC filter circuit is connected in series with the pre-charge circuit and is used to filter the signal output by the pre-charge circuit to filter out the voltage harmonics on the DC side and transmit the processed signal to the power switch device.

[0068] As a preferred solution, please refer to Figure 1 , the power circuit further includes: an AC filter circuit.

[0069] Among them, please refer to Figure 1 , the AC filter circuit is connected in series with the power switch device and is used to filter the signal output by the power switch device to filter out the high-frequency voltage and current harmonics on the AC side and transmit the processed signal to the voltage-current sensor.

[0070] Embodiment 2:

[0071] Please refer to Figure 1, which is a PCB board layout structure provided by an embodiment of the present invention. This structure includes: three PCB sub-boards, namely a signal board, a drive board, and a power board, arranged from top to bottom in sequence; each PCB sub-board contains an interface for connecting to other PCB sub-boards.

[0072] In this embodiment, the power converter includes a signal loop and a power loop. Among them, the signal loop includes a control circuit, a sampling circuit, a drive circuit, and an auxiliary power supply, with a voltage within 24V and a current within 100mA; the power loop includes a pre-charge circuit, a DC filter circuit, a power switch device, an AC filter circuit, a voltage and current sensor, with a voltage around 800V and a maximum current reaching 100A. In the signal loop, the auxiliary power supply provides working voltages of 24V, 12V, 5V, and 3.3V to supply power to chips or sensor devices in each part of the circuit; the sampling circuit needs to be connected to the voltage and current sensors in the power loop, and after processing the voltage and current signals, it gives them to the control circuit; the control circuit controls the pre-charge circuit at the initial stage of product operation, and during continuous product operation, it will adjust the control strategy in real time according to the received voltage and current signals, and transmit the control signal to the drive circuit; the drive circuit forms a drive signal with a certain driving ability after a series of level conversions of the control signal, and then gives it to the power switch device, so that the switch device performs continuous high-speed on-off actions, thereby realizing the power conversion function of the entire product. Specifically, the control signal is a signal of several tens of microamps and cannot make the switch device act, and the drive signal is a signal of -4V / +15V. When it is -4V, the power device generates an off action, and when it is +15V, the power device generates an on action. Among them, the switching frequency of the power switch device is 50kHz, that is, the interval between on and off is about 20us.

[0073] Among them, the signal board is used to sample the output of the power board and correspondingly output a control signal. Please refer to Figure 2 of (b). Signal traces are arranged in both the top layer (i.e., the first signal layer) and the bottom layer (i.e., the last signal layer) of the signal board.

[0074] In this embodiment, please refer to Figure 1 , the signal board contains a sampling circuit, a control circuit, and an auxiliary power supply. The signal board has control signal, sensor signal, and power interfaces connected to the power board, as well as a control signal interface connected to the drive board; the drive board only has the drive circuit part, with a control signal interface connected to the signal board and a drive signal interface connected to the power board; the power board only contains all the power loops, with the aforementioned interfaces connected to the signal board and the drive board.

[0075] As a preferred solution, please refer to Figure 2In (b) thereof, between the top layer and the bottom layer of the signal board, there is also an auxiliary power supply layer and an auxiliary power supply ground layer, constituting a four-layer PCB board wiring scheme of the signal board, which is applicable to the case of higher circuit complexity.

[0076] Among them, the auxiliary power supply layer is provided with auxiliary power supply traces and an auxiliary power supply for supplying power to the signal board and the drive board; the auxiliary power supply ground layer is provided with a signal ground.

[0077] In this embodiment, some signal lines can also be arranged in the auxiliary power supply layer and the auxiliary power supply ground layer of the signal board.

[0078] As a preferred solution, a PCB board layout structure of a power converter provided by an embodiment of the present invention further includes:

[0079] A sampling circuit is arranged in the top layer of the signal board, and a control circuit is arranged in the bottom layer of the signal board; or, a control circuit is arranged in the top layer of the signal board, and a sampling circuit is arranged in the bottom layer of the signal board.

[0080] Among them, the sampling circuit is used to perform real-time sampling on the voltage signal or current signal output by the power board and output a sampling signal; the control circuit is used to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the drive board.

[0081] Among them, please refer to Figure 1 , the drive board includes a drive circuit for generating and outputting a drive signal in response to the control signal, please refer to Figure 3 , signal traces are arranged in the top layer of the drive board, and auxiliary power supply traces and a signal ground are arranged in the bottom layer of the drive board.

[0082] As a preferred solution, please refer to Figure 3 , auxiliary power supply traces and a signal ground are also arranged in the top layer of the drive board, and the number of auxiliary power supply traces and signal ground in the top layer of the drive board is less than the number of signal traces in the top layer of the drive board; signal traces are also arranged in the bottom layer of the drive board, and the number of signal traces in the bottom layer of the drive board is less than the number of auxiliary power supply traces and signal ground in the bottom layer of the drive board. That is, in the top layer of the drive board, mainly signal traces are arranged, and a small number of auxiliary power supply traces and signal ground are also arranged; while in the bottom layer of the drive board, mainly auxiliary power supply traces and signal ground are arranged, and a small number of signal traces are also arranged.

[0083] Among them, please refer to Figure 1 , the power board includes a power loop, and the power loop includes a power switch device for performing on-off actions in response to the drive signal to achieve power conversion, please refer to Figure 4 , power traces are arranged in both the top layer (i.e., the first signal layer) and the bottom layer (i.e., the last signal layer) of the power board. Please refer toFigure 1 , the drive board is placed directly above the power switch device.

[0084] As a preferred solution, please refer to Figure 4 , between the top layer and the bottom layer of the power board, there is also an auxiliary power supply layer and an auxiliary power supply ground layer. A fifth preset number of power traces are arranged in the top layer of the power board, a seventh preset number of power traces are arranged in the bottom layer of the power board, a sixth preset number of signal traces and power traces are arranged in the auxiliary power supply layer, and an eighth preset number of signal traces, power traces and signal ground are arranged in the auxiliary power supply ground layer, constituting a four-layer PCB board wiring solution for the power board, which is applicable to the case of higher circuit complexity.

[0085] Among them, the fifth preset number is greater than the sixth preset number, and the seventh preset number is greater than the eighth preset number.

[0086] In this embodiment, some signal lines can also be arranged in the auxiliary power supply layer and the auxiliary power supply ground layer of the power board.

[0087] In this embodiment, the power board is generally relatively large and is often fixed on the product chassis. The drive board is smaller in size and has a strong correlation with the power switch device area on the power board. The drive board can be vertically inserted above the power switch area by using the hard connection method of pin-header. The signal board is medium in size and can be supported on the power board or fixed on the upper case of the chassis. There may be multiple connections between the signal board and the drive board and the power board, and multiple flexible cables can be used for connection. When necessary, a shielding layer can be wrapped to reduce interference.

[0088] As a preferred solution, please refer to Figure 1 , the power circuit further includes: a voltage and current sensor.

[0089] Among them, the voltage and current sensor is used to detect the voltage or current flowing through the power circuit, convert the detected voltage or current, and then transmit the converted signal to the signal board.

[0090] As a preferred solution, please refer to Figure 1 , the power circuit further includes: a pre-charge circuit and a DC filter circuit connected in series in the power circuit.

[0091] Among them, the pre-charge circuit includes a pre-charge resistor and a bypass relay connected in parallel with the pre-charge resistor; the pre-charge circuit is connected to the output interface of the signal board.

[0092] The pre-charge circuit is used to short-circuit the pre-charge resistor when receiving the control signal output by the signal board.

[0093] Please refer to Figure 1, a DC filtering circuit, connected in series with the pre-charging circuit, is used to filter the signal output by the pre-charging circuit to filter out the voltage harmonics on the DC side and transmit the processed signal to the power switching device.

[0094] As a preferred solution, please refer to Figure 1 , the power loop further includes: an AC filtering circuit;

[0095] Among them, please refer to Figure 1 , the AC filtering circuit, connected in series with the power switching device, is used to filter the signal output by the power switching device to filter out the high-frequency voltage and current harmonics on the AC side and transmit the processed signal to the voltage and current sensors.

[0096] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0097] The present invention provides a PCB board layout structure for a power converter, which sequentially includes a signal board, a driver board, and a power board from top to bottom. An auxiliary power supply trace and a signal ground are arranged in the bottom layer of the driver board, and the signal ground is used as a shielding layer to avoid the influence of electromagnetic radiation generated in the power switch device area on the signal loop, especially the drive circuit. Among them, the signal board is used to sample the output of the power board and correspondingly output a control signal. Signal traces are arranged in both the top layer and the bottom layer of the signal board to ensure low delay and low noise in signal transmission. The driver board includes a drive circuit that generates and outputs a drive signal in response to the control signal. Signal traces are arranged in the top layer of the driver board, and an auxiliary power supply trace and a signal ground are arranged in the bottom layer of the driver board, which helps to reduce signal interference and improve the stability of the drive signal. As for the power board, power traces are arranged in both the top layer and the bottom layer, and the power switch devices in the power loop can directly respond to the drive signal to perform on-off actions, optimizing the power conversion process and improving the working efficiency of the power converter. In addition, placing the driver board directly above the power switch devices in the power board can reduce the transmission path length of the drive signal, reduce signal loss and interference. This tightly coupled design helps to improve the response speed and switching efficiency of the power switch devices, thereby enhancing the efficiency of the entire power converter. Further, the entire system is designed modularly according to functions, only the connection points of each sub-module are retained, and the rest of the circuits are completely decoupled, that is, the signal board, the driver board, and the power board are connected through interfaces, separating the signal loop and the power loop, reducing the electromagnetic interference that may be generated during the power conversion process, and the drive chip in the driver board can be isolated from the long-term high-temperature environment where the power switch devices are located, ensuring the long-term stable operation of the drive chip. Except for the interfaces of each PCB sub-board, the rest of the circuits are completely decoupled and do not interfere with each other. This not only facilitates multi-person collaborative development and improves efficiency, but also enables only the corresponding PCB sub-board to be replaced when a certain part needs to be upgraded or replaced, without having to redesign the entire system, so as to reduce the maintenance cost.

[0098] In the above specific embodiments, the purpose, technical solutions, and beneficial effects of the present invention are further described in detail. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. In particular, for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A PCB board layout structure of a power converter, characterized in that Including: Three PCB daughter boards, namely a signal board, a driver board, and a power board, from top to bottom in sequence; each PCB daughter board includes an interface for connecting to other PCB daughter boards; Among them, the signal board is used to sample the output of the power board and correspondingly output a control signal, and signal traces are arranged on both the top layer and the bottom layer of the signal board; The driver board includes a driving circuit for generating and outputting a driving signal in response to the control signal, signal traces are arranged on the top layer of the driver board, and auxiliary power traces and signal ground are arranged on the bottom layer of the driver board; The power board includes a power loop, and the power loop includes a power switch device for performing on-off actions in response to the driving signal to achieve power conversion. Power traces are arranged on both the top layer and the bottom layer of the power board, and the driver board is placed directly above the power switch device.

2. The PCB board layout structure of a power converter according to claim 1, characterized in that On the top layer of the signal board, a first preset number of signal traces, a second preset number of auxiliary power traces and signal ground, a sampling circuit, and a control circuit are arranged. On the bottom layer of the signal board, a third preset number of auxiliary power traces and signal ground, a fourth preset number of signal traces, and an auxiliary power supply for powering the signal board and the driver board are arranged; Among them, the first preset number is greater than the second preset number, and the third preset number is greater than the fourth preset number; the sampling circuit is used to perform real-time sampling on the voltage signal or current signal output by the power board and output a sampling signal; the control circuit is used to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the driver board.

3. The layout structure of a power converter PCB board as described in claim 1, characterized in that, Between the top layer and the bottom layer of the signal board, there is also an auxiliary power layer and an auxiliary power ground layer; Among them, auxiliary power traces and an auxiliary power supply for powering the signal board and the driver board are arranged in the auxiliary power layer; Signal ground is arranged in the auxiliary power ground layer.

4. The layout structure of a power converter PCB board according to claim 3, wherein, Also including: A sampling circuit is arranged on the top layer of the signal board, and a control circuit is arranged on the bottom layer of the signal board; Or, a control circuit is arranged on the top layer of the signal board, and a sampling circuit is arranged on the bottom layer of the signal board; Among them, the sampling circuit is used to perform real-time sampling on the voltage signal or current signal output by the power board and output a sampling signal; the control circuit is used to adjust the control strategy in real time according to the sampling signal, generate a control signal corresponding to the adjusted control strategy, and then transmit the control signal to the driver board.

5. The layout structure of a power converter PCB board according to claim 1, wherein, The power loop further includes: a voltage-current sensor; Among them, the voltage-current sensor is used to detect the voltage or current flowing through the power loop, perform conversion processing on the detected voltage or current, and then transmit the converted signal to the signal board.

6. The layout structure of a power converter PCB board according to claim 5, wherein, The power loop further includes: a pre-charge circuit and a DC filter circuit connected in series in the power loop; Among them, the pre-charge circuit includes a pre-charge resistor and a bypass relay connected in parallel with the pre-charge resistor; The pre-charge circuit is connected to the output interface of the signal board; The DC filtering circuit, connected in series with the pre-charge circuit, is configured to filter the signal output by the pre-charge circuit to filter out the voltage harmonics on the DC side and transmit the processed signal to the power switching device.

7. The layout structure of a power converter PCB board according to claim 6, wherein, The power loop further includes: an AC filtering circuit; Wherein, the AC filtering circuit, connected in series with the power switching device, is configured to filter the signal output by the power switching device to filter out the high-frequency voltage and current harmonics on the AC side and transmit the processed signal to the voltage and current sensor.

8. The layout structure of a power converter PCB board according to claim 7, characterized in that, A fifth preset number of power traces and a sixth preset number of signal traces are arranged in the top layer of the power board, and a seventh preset number of power traces, an eighth preset number of signal traces and a signal ground are arranged in the bottom layer of the power board; Wherein, the fifth preset number is greater than the sixth preset number, and the seventh preset number is greater than the eighth preset number.

9. The layout structure of a power converter PCB board according to claim 7, wherein, Between the top layer and the bottom layer of the power board, an auxiliary power supply layer and an auxiliary power supply ground layer are further included; Wherein, a fifth preset number of power traces are arranged in the top layer of the power board, a seventh preset number of power traces are arranged in the bottom layer of the power board, a sixth preset number of signal traces and power traces are arranged in the auxiliary power supply layer, and an eighth preset number of signal traces, power traces and signal ground are arranged in the auxiliary power supply ground layer; The fifth preset number is greater than the sixth preset number, and the seventh preset number is greater than the eighth preset number.

10. A PCB board layout structure of a power converter as described in claim 1, characterized in that, Auxiliary power supply traces and a signal ground are further arranged in the top layer of the drive board, and the number of the auxiliary power supply traces and the signal ground in the top layer of the drive board is less than the number of the signal traces in the top layer of the drive board; signal traces are further arranged in the bottom layer of the drive board, and the number of the signal traces in the bottom layer of the drive board is less than the number of the auxiliary power supply traces and the signal ground in the bottom layer of the drive board.

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