A vehicle-mounted PoDL power supply system supporting bidirectional power supply and dynamic power scheduling, and an execution method of dynamic power scheduling and reverse power supply control

Abstract

The present application relates to the field of data line power supply, and specifically proposes a vehicle-mounted PoDL power supply system supporting bidirectional power supply and dynamic power scheduling, and an execution method of dynamic power scheduling and reverse power supply control, the system comprising a power supply device and at least one powered device, the power supply device comprising a main / backup power supply interface, a bidirectional power converter, a power management controller, a port monitoring module and a data exchange module, the powered device comprising a power supply extraction circuit, a controller and a reverse power supply circuit. The present application solves the interoperability problem between different supplier devices in a vehicle-mounted environment through a lightweight handshake protocol compatible with IEEE 802.3bu, and adopts a reconfigurable bidirectional power converter, so that the system can not only realize dynamic power scheduling based on real-time load and priority, but also switch to a reverse power supply mode when the main power supply fails, and obtain emergency power from a capable powered device, thereby enhancing the flexibility and reliability of the vehicle-mounted power supply network.

Description

Technical Field

[0001] This invention relates to the field of power supply technology for data cables, and more particularly to an on-board PoDL power supply system that supports bidirectional power supply and dynamic power scheduling, as well as a method for executing dynamic power scheduling and reverse power supply control. Background Technology

[0002] Onboard PoDL can simplify the testing process, but it is actually a double-edged sword. Due to the lack of a unified handshake protocol between PSE and PD, there is a risk of power-on timing mismatch or overvoltage damage between cameras from different suppliers and domain controllers from different brands. As a result, OEMs often need to customize additional testing circuits or firmware protocols to ensure safe plugging and unplugging and hot start, which undoubtedly increases development and testing costs.

[0003] The power supply process of the existing PoDL system is divided into four consecutive stages: (1) Detection stage The PSE applies a constant current source of approximately 9mA to 16mA to the port. By detecting voltage changes in the detection loop, it determines whether a compliant PD exists. If a valid PD is detected, the process proceeds to the next stage; otherwise, the port is not powered.

[0004] (2) Grading stage The PSE applies a graded voltage to the PD, and the PD sends back a characteristic current according to its own power requirements. Based on this, the PSE classifies the PD into different power levels, namely Class 0 to 8. Class 0 to 4 correspond to a power range of approximately 0.44W to 25.5W, while Class 5 to 8 correspond to higher power. The highest power requirement of Class 8 PD can reach 71W, which is the maximum received power of the PD.

[0005] (3) Power supply stage After the classification is completed, the PSE starts full-voltage power supply, and the PD begins normal operation. During the power supply process, the PSE continuously monitors the port current and power; if the actual load power of the PD exceeds its declared classification budget, or if a fault such as a short circuit or overload occurs, the PSE will cut off the power supply to that port and wait for a period of time before restarting the monitoring.

[0006] (4) Power management mechanism Existing technology uses a static power budget allocation method. The total power of the PSE is limited. During system initialization, the administrator or PSE controller pre-allocates a fixed power budget to each port based on the classification information of the PDs connected to each port. After the budget is allocated, even if the PD does not reach the budget value during actual operation, the remaining power cannot be used by other ports. When a new PD is connected, if the remaining total power is insufficient to meet its classification budget, the port cannot receive power.

[0007] Existing PoDL systems have at least the following technical problems: 1. Limited power supply capacity makes it difficult to meet the needs of high-power devices. Existing PoDL power supply technology is limited by cable losses, power supply equipment power budgets, and standard protocol constraints, typically restricting the output power of a single port to a low range, such as 30W or 60W or less. When the powered device is a high-power device, such as a high-power wireless AP, a PTZ camera, or an industrial terminal, existing technologies require additional power cables or non-standard power supply solutions, increasing system complexity and deployment costs.

[0008] 2. Low power supply efficiency and high energy loss. In existing power supply schemes, the power transmission path usually goes through multiple stages of transformation, such as DC-DC boost at the PSE end, cable transmission, and step-down at the PD end. When transmitting over long distances or when the load fluctuates greatly, the overall conversion efficiency decreases, and a large amount of electrical energy is dissipated as heat in the cables and conversion circuits, which not only wastes energy but also puts pressure on the heat dissipation of equipment.

[0009] 3. Poor power supply stability, susceptible to data signal interference. In power-on-a-data-line (POD) technology, power and data signals share the same wire pair. Existing technologies often employ simple power superposition and separation methods. When the data transmission rate increases or the cable length increases, power ripple is easily coupled to the data channel, leading to an increase in the data error rate. At the same time, high-speed data signals may also interfere with the power supply circuit in the reverse direction, causing voltage fluctuations at the receiving end, affecting the stable operation of the equipment, or even triggering protective power-off.

[0010] 4. Lack of sophisticated power management capabilities Existing PoDL power supply systems mostly adopt a static power allocation method, which reserves power for each port according to a fixed budget. This method cannot dynamically adjust power according to the real-time load of the powered equipment, resulting in low power utilization of the power supply equipment. Some ports are idle while others cannot start or operate normally due to insufficient power. In addition, existing technologies are difficult to achieve intelligent scheduling, priority management, and fault isolation of multiple power supplies, resulting in insufficient overall power supply flexibility of the system.

[0011] 5. Unable to meet functional requirements in specific scenarios. In special application scenarios requiring reverse power supply, redundant power supply, hybrid power supply from batteries and data cables, or power outage retention, the existing PoDL power supply architecture is rigid and cannot flexibly configure the power supply direction or achieve seamless switching between multiple power sources. For example, when the main power supply is interrupted, the existing system cannot automatically switch to the backup power supply and maintain data transmission, resulting in the downtime of critical equipment.

[0012] 6. Excessive cost To achieve long-distance, high-power power supply, existing technologies often require high-specification cables, complex power management chips, and additional heat dissipation structures. At the same time, to meet the compliance requirements of standard protocols such as IEEE 802.3bt, the circuit design of power supply equipment and power receiving equipment is complex, and the material costs and R&D and debugging costs are high, which limits the promotion of PoDL power supply technology in cost-sensitive applications.

[0013] To address the above technical issues, this invention designs a lightweight handshake protocol that is compatible with IEEE 802.3bu and suitable for automotive applications. Summary of the Invention

[0014] This invention proposes an on-board PoDL power supply system that supports bidirectional power supply and dynamic power scheduling, as well as an execution method for dynamic power scheduling and reverse power supply control. This solves the problem of poor interoperability in current solutions and supports dynamic power scheduling and bidirectional power supply.

[0015] The technical solution is as follows: In the first aspect, an on-board PoDL power supply system supporting bidirectional power supply and dynamic power scheduling is proposed, including a power supply device and at least one power receiving device connected to the power supply device via an Ethernet cable. The power supply equipment includes: Main power interface, used to connect to an external main power supply; Backup power interface, used to connect a backup power source; A bidirectional power converter, whose input terminals are electrically connected to the main power interface and the backup power interface respectively, and whose output terminals are electrically connected to multiple power supply ports, is configured as an isolated DC-DC conversion circuit and can switch between forward and reverse modes. A power management controller, connected to the bidirectional power converter, is used to control the switching of the bidirectional power converter's operating mode and to perform dynamic power scheduling and reverse power supply control. A port monitoring module is set up one-to-one with each power supply port to monitor the electrical parameters of each power supply port and report them to the power management controller; A data exchange module, connected to the plurality of power supply ports and the power management controller, is used to transmit standard Ethernet data frames and power scheduling command frames; The memory is connected to the power management controller; The power receiving device includes: A power extraction circuit for extracting power through the Ethernet cable; The power receiving device controller is used to interact with the power supply device via a handshake protocol and parse the power scheduling instruction frame; A DC-DC converter converts the input voltage into the internal operating voltage of the powered device. A reverse power supply circuit is used to feed the power of the powered device to the Ethernet cable in reverse power supply mode.

[0016] According to one embodiment of the present invention, the bidirectional power converter adopts a full-bridge isolated DC-DC converter topology, comprising: The first full-bridge circuit has its input terminal connected to the main power interface and / or the backup power interface; The second full-bridge circuit has its output connected to the plurality of power supply ports; A high-frequency transformer, wherein the primary winding is connected to the first full-bridge circuit and the secondary winding is connected to the second full-bridge circuit; A resonant inductor is connected in series in the primary winding circuit of the high-frequency transformer; A resonant capacitor is connected in parallel across the primary winding of the high-frequency transformer.

[0017] According to an embodiment of the present invention, performing the dynamic power scheduling includes the following steps: Step S1: System initialization, initialize the total power pool; Step S2: When a powered device is connected to the power supply port, the power management controller obtains the maximum power requirement of the powered device; Step S3: If the maximum power demand is less than or equal to the current remaining power pool, then power is allocated to the power supply port and power is turned on; if it is greater, then the priority arbitration mechanism is activated. Step S4: The priority arbitration mechanism includes: the power management controller selects the powered port according to the preset priority, requests it to reduce the power allocation, the released power is recovered to the power pool, and step S3 is re-executed; Step S5: During the power supply process, the power allocation of each port is dynamically adjusted according to the real-time power reported by the port monitoring module, and the power surplus is recovered to the power pool, or additional power is allocated from the power pool.

[0018] According to one embodiment of the present invention, performing the reverse power supply control includes the following steps: Step A: The power management controller continuously monitors the input voltage of the main power interface; Step B: When the input voltage of the main power interface is lower than the first voltage threshold and the duration exceeds the first time threshold, the reverse power supply mode is activated; Step C: Detect the backup power interface. If there is no backup power or the backup power voltage is invalid, send a reverse power supply request frame to each powered device through the data exchange module. Step D: When a reverse power supply confirmation frame is received from at least one powered device, the bidirectional power converter is controlled to switch to reverse mode and the reverse power supply circuit of the powered device is enabled, so that the powered device supplies power to the power supply device. Step E: When the input voltage of the main power interface recovers to above the second voltage threshold and the duration exceeds the second time threshold, control the bidirectional power converter to switch back to forward mode, restore the main power supply, and send a reverse power supply termination command to the powered device.

[0019] Wherein, the first voltage threshold is 10V, the first time threshold is 10 milliseconds; the second voltage threshold is 10V, and the second time threshold is 50 milliseconds.

[0020] The powered device is a vehicle-mounted camera, vehicle-mounted radar, vehicle-mounted infotainment system, or vehicle-mounted control unit.

[0021] Secondly, a power supply device for the vehicle-mounted PoDL power supply system described in the first aspect is proposed. The power supply device includes the main power interface, the backup power interface, the bidirectional power converter, the power management controller, the port monitoring module, and the data exchange module.

[0022] Thirdly, a power receiving device is proposed for use in the vehicle-mounted PoDL power supply system described in the first aspect above. The power receiving device includes the power extraction circuit, the power receiving device controller, the DC-DC converter, and the reverse power supply circuit.

[0023] Fourthly, a dynamic power scheduling method for an on-board PoDL power supply system is proposed, executed by a power management controller in the power supply system as described in the first aspect, including: Initialize the total power pool; When a new power-receiving device is connected, its maximum power requirement is obtained; If the current remaining power pool capacity meets the demand, power is allocated and power is supplied; if not, according to the preset priority, the low-priority devices that are already powered are requested to reduce their power to release power resources. During equipment operation, the actual power of each port is continuously monitored. Excess power where the difference between the actual power and the allocated power exceeds a first threshold is recycled to the power pool. When the actual power is close to the allocated power, additional power is allocated from the power pool.

[0024] Fifthly, a reverse power supply control method for an on-board PoDL power supply system is proposed, executed by a power management controller in the power supply system as described in the first aspect, comprising: Monitor the main power supply status of the power supply equipment; When the main power supply fails and there is no available backup power supply, a reverse power supply request is broadcast to the powered devices in the network. Receive confirmation responses from powered devices that support reverse power supply functionality; The power converter inside the power supply equipment is switched to reverse working mode to accept power from the power receiving equipment in order to maintain the operation of the critical functions of the power supply equipment. When the main power supply is restored, switch back to normal power supply mode and notify the powered equipment to stop feeding power.

[0025] Compared with the prior art, the present invention has achieved at least the following technical effects: 1. Resolved the technical issues of power-on timing mismatch and overvoltage damage caused by inconsistent protocols between cameras and domain controllers from different suppliers.

[0026] 2. It improves the utilization efficiency of the total power of the power supply equipment, avoiding the problem that some ports are idle while other ports cannot be started due to insufficient power budget. Under the same total power budget, it can support more or higher power receiving equipment, improving the overall flexibility and economy of the system.

[0027] 3. By adopting a bidirectional power converter, in extreme cases where the main power supply fails and there is no backup power supply, the system can use the power of other devices in the network to maintain the operation of critical functions, providing emergency power protection for the system, realizing a certain degree of redundant power supply, and meeting the needs of high reliability scenarios.

[0028] 4. By adopting a full-bridge isolated topology and adding resonant inductors and capacitors, energy loss during transmission and conversion is reduced, heat dissipation pressure is lowered, and stable power supply quality also helps to reduce interference to high-speed data signals, ensuring the stability of data transmission.

[0029] 5. The power supply equipment integrates a power management controller, a bidirectional power converter, a data exchange module, and a port monitoring module, forming a complete intelligent power supply management unit. This simplifies the design of the vehicle's electrical architecture, and a single Ethernet cable solves the data and power transmission problems. Attached Figure Description

[0030] Figure 1 This is a basic system block diagram of an embodiment of the present invention; Figure 2 The circuit diagram for the first full-bridge circuit section of the bidirectional power converter is shown below. Figure 3 This is a circuit diagram of the second full-bridge circuit section in a bidirectional power converter. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1 See Figure 1 The system block diagram shown indicates that the vehicle-mounted PoDL power supply system mainly includes a power supply device (PSE) and at least one power receiving device (PD), which are connected by a shielded or unshielded Ethernet cable that meets the requirements of vehicle applications. This Ethernet cable can transmit power and data signals simultaneously.

[0033] The core function of the power supply equipment is to act as an intelligent power supply and energy dispatch center, providing stable, flexible, and reliable power to various electrical devices in the vehicle network. The power supply equipment specifically includes the following components: chassis, power interface board, control motherboard, and multiple power supply ports. The power interface board is equipped with a main power interface and a backup power interface. The main power interface connects to a 12V DC power adapter, and the backup power interface connects to a 12V lead-acid battery pack. The control motherboard integrates a power management controller, a bidirectional power converter, a data exchange module, and a memory. The power management controller uses a microcontroller of model MSP430FR2476TRHBR, which operates at a frequency of 168 MHz and has three built-in 12-bit analog-to-digital converters and 17 timers. The data exchange module uses an Ethernet switching chip supporting the IEEE 802.3bt standard, model YT8010AN.

[0034] The main power interface is used to connect to the external vehicle's main power system, such as a 12V or 24V vehicle battery or the output of a DC-DC converter. This interface typically includes necessary input filtering, overvoltage protection, and reverse connection protection circuitry to ensure the quality of the input power and the safety of the powered equipment. The backup power interface is used to connect to backup power sources, such as supercapacitor modules, auxiliary batteries, or other emergency power supplies. This interface serves as a backup energy source for the system in the event of a main power failure. The interface circuit design incorporates isolation or automatic switching logic from the main power supply to prevent mutual interference between power sources.

[0035] The input of the bidirectional power converter can be selectively connected to the main power interface and the backup power interface via a selector switch, diode, or logic circuit. Its output is connected to multiple power supply ports. Essentially, this bidirectional power converter is an isolated DC-DC converter that can flexibly switch between two modes under the control of a signal. Forward mode: In this mode, the bidirectional power converter operates as a standard isolated DC-DC buck or buck-boost converter, with power flowing from the input to the output to power connected devices. Reverse mode: In this mode, the operating state of the bidirectional power converter is reversed. Its control logic allows power to flow from the output to the input. In this mode, the input acts as a load, receiving power from the Ethernet cable and supplying it to the low-voltage bus inside the power supply equipment to maintain the operation of critical circuits such as the power management controller and data exchange module, or to charge the backup power supply.

[0036] The power management controller, typically composed of a microcontroller unit or digital signal processor, connects to the control pins of the bidirectional power converter. By generating PWM signals or other control logic, it controls the on / off switching of power transistors in the converter, thereby switching operating modes and regulating output voltage / current. Port monitoring modules are configured independently for each power supply port or shared via a multiplexer. Each port monitoring module includes voltage sampling circuitry, current sampling circuitry, and an analog-to-digital converter. It continuously monitors the output voltage and current of the corresponding port at a high frequency and calculates the real-time power, which is reported to the power management controller in real time. The data exchange module processes standard Ethernet frames, facilitating data exchange between multiple power supply ports and between ports and the upstream network. Through this module, the power management controller can send specific Ethernet frames carrying power scheduling commands to powered devices or receive response frames from powered devices.

[0037] The powered device can be any power-consuming unit in the vehicle network, such as a high-definition camera, millimeter-wave / LiDAR, infotainment display, domain control unit, etc. Each powered device includes a power extraction circuit, a powered device controller, a DC-DC converter, and a reverse power supply circuit.

[0038] The power extraction circuit is typically located after the Ethernet connector on the powered device. Its core is the PoDL signal separation circuit, which separates the DC power superimposed on the data signal in the Ethernet cable. This circuit usually includes a common-mode choke and an isolation transformer to minimize interference between data and power, outputting an unregulated DC voltage. The powered device controller is typically a microcontroller that executes the handshake protocol with the power supply. During device startup, it mimics the behavior of a power PD in standard PoDL, responding to PSE detection and grading signals and declaring its own power demand level. During normal operation, it continuously listens for frames from the data link layer, parses power dispatch command frames sent by the power supply, and makes corresponding responses or adjustments.

[0039] A DC-DC converter is a standard isolated or non-isolated DC-DC buck converter that converts an unstable DC voltage (e.g., a value within the range of 12V-48V) obtained from the power extraction circuit into one or more stable voltages required by the chips and circuits inside the powered device, such as 5V, 3.3V, 1.8V, etc. The reverse power supply circuit is an additional circuit designed to enable energy feedback capability in the powered device. In forward power supply mode, this circuit is disabled or bypassed. When the powered device controller interprets a reverse power supply request command from the power supply device and has its own reverse power supply capability, the circuit is activated. Once activated, it can boost the energy from the device's internal battery or energy storage components and then inject DC power back into the Ethernet cable through the power extraction circuit. This process needs to be synchronized with the power supply device's bidirectional power converter switching to reverse mode to prevent voltage conflicts.

[0040] Example 2 This embodiment elaborates in detail on the specific circuit topology of the bidirectional power converter in the aforementioned embodiment 1 and its working principle in forward and reverse modes.

[0041] The bidirectional power converter adopts a full-bridge isolated resonant converter topology, which includes a first full-bridge circuit, a second full-bridge circuit, a high-voltage frequency converter, and a resonant network composed of a resonant inductor and a resonant capacitor. The relevant circuit connections are as follows: See Figure 2As shown, the first full-bridge circuit consists of a first power switch, a second power switch, a third power switch, and a fourth power switch. Q8 represents the first power switch, Q9 represents the second power switch, and U24 represents the third and fourth power switches. The drain of the first power switch is connected to the positive terminal of the main power interface, and its source is connected to the drain of the second power switch, which in turn is connected to the negative terminal of the main power interface. Similarly, the drain of the third power switch is connected to the positive terminal of the main power interface, its source is connected to the drain of the fourth power switch, and its source is connected to the negative terminal of the main power interface. All four power switches are IRF3205 N-channel metal-oxide-semiconductor field-effect transistors, with a drain-source breakdown voltage of 55 volts and an on-resistance of 8 milliohms.

[0042] See Figure 3 As shown, the second full-bridge circuit consists of a fifth, sixth, seventh, and eighth power switch transistor. U21 represents the fifth and sixth power switches, and U17 represents the seventh and eighth power switches. Its connection method is the same as the first full-bridge circuit, connected to the busbars of multiple power supply ports. The fifth to eighth power switches use the same model as the first to fourth power switches.

[0043] The primary winding of the high-frequency transformer is connected to the connection points of the source and drain of the first and second power switches, and the source and drain of the third and fourth power switches, respectively. The secondary winding is connected to the connection points of the source and drain of the fifth and sixth power switches, and the source and drain of the seventh and eighth power switches, respectively. The high-frequency transformer uses an EE55 ferrite core, with 24 turns in both the primary and secondary windings, a turns ratio of 1:1, and an operating frequency of 100 kHz.

[0044] The resonant inductor is connected in series in the primary winding circuit of the high-frequency transformer, with an inductance of 10 microhenries, and is made of iron-silicon-aluminum magnetic rings; the resonant capacitor is connected in parallel across the primary winding of the high-frequency transformer, with a capacitance of 0.47 microfarads, and is made of polypropylene film capacitor.

[0045] The controller interface connects the eight pulse-width modulation (PWM) outputs of the power management controller to the gates of the first through eighth power switches, respectively, and adjusts the power flow direction and magnitude by controlling the turn-on timing of each switch. The controller interface is connected to the power management controller and receives PWM control signals.

[0046] The forward mode operation process, which is the power supply equipment supplying power to the power receiving equipment, is as follows: When the power management controller detects that the main power interface voltage is 12 volts and stable, it configures the bidirectional power converter to forward mode. The power management controller outputs a forward pulse width modulation signal to drive the first full-bridge circuit as the primary side and the second full-bridge circuit as the secondary side.

[0047] In forward mode, the first full-bridge circuit inverts the 12V DC power from the main power supply into an AC square wave, which is then transmitted to the secondary side via a high-frequency transformer. The second full-bridge circuit rectifies the AC square wave into DC power and outputs it to the power supply port bus. The duty cycle of the pulse width modulation signal can be adjusted from 0% to 95%. By adjusting the duty cycle, the output voltage can be changed, ranging from 0V to 11V.

[0048] The reverse mode operation, where the powered device feeds power to the powered device, proceeds as follows: When the power management controller detects that the main power interface voltage is below 10 volts for 10 milliseconds, it determines that the main power supply is faulty. At this time, if the backup power interface voltage is 0 volts, the power management controller sends a reverse power supply request frame to each powered device through the data exchange module. When the second powered device returns a reverse power supply confirmation frame, the power management controller configures the bidirectional power converter to reverse mode. The power management controller outputs a reverse pulse width modulation signal to drive the second full-bridge circuit as the primary side and the first full-bridge circuit as the secondary side. The power of the second powered device is fed into the power supply port via an Ethernet cable, inverted by the second full-bridge circuit, transmitted by the high-frequency transformer, and rectified by the first full-bridge circuit before being output to the power management controller and the data exchange module to maintain its operation.

[0049] Finally, when the main power is restored, the power management controller detects that the main power interface voltage has risen back to above 10 volts and lasts for 50 milliseconds. It then switches the bidirectional power converter back to forward mode, restores the main power supply, and sends a reverse power supply termination command to the second powered device through the data exchange module.

[0050] The bidirectional power converter, through its symmetrical full-bridge topology, achieves bidirectional transmission without requiring additional switching devices in the same hardware circuit; it only needs to change the logic of the control signals. Meanwhile, the power management controller ensures a stable and compliant voltage output under different modes and load conditions by sampling the voltage and current at the input and output terminals in real time.

[0051] Example 3 This embodiment describes in detail the specific process of the power management controller executing the dynamic power scheduling method.

[0052] Step 1: System initialization, initialize the total power pool, and set the initial power allocation of each power supply port to zero.

[0053] Step 2: When a powered device is connected to any power supply port, the port monitoring module detects the connection event, and the power management controller obtains the maximum power requirement of the powered device.

[0054] Step 3: If the maximum power demand is less than or equal to the current remaining power pool, the power management controller allocates power equal to the maximum power demand to the power supply port and starts power supply through the bidirectional power converter; if the maximum power demand is greater than the current remaining power pool, the priority arbitration mechanism is activated.

[0055] Step 4: The priority arbitration mechanism includes: the power management controller selects the lowest priority powered port according to the preset priority, sends a power adjustment request frame to the powered device connected to the port, and requests a reduction in power; if the powered device returns an acknowledgment frame, the allocated power of the port is reduced, the released power is added back to the remaining power pool, and step 3 is executed again; if the powered device refuses or does not respond, the second lowest priority port is selected and the above process is repeated.

[0056] Step 5: During power supply, the port monitoring module continuously samples the real-time voltage and current of each port at a sampling frequency of 2kHz and reports it to the power management controller every 100 milliseconds. The power management controller calculates the power margin of each port. When the power margin is greater than 10 watts and lasts for 2 seconds, the allocated power of the port is reduced to the real-time power plus 5 watts of reserved margin, and the power is released back into the power pool. When the difference between the real-time power and the allocated power is less than 2 watts and lasts for 500 milliseconds, if the remaining power pool is greater than zero, the allocated power of the port is increased by a step value of 5W until the demand is met or the maximum power limit is reached.

[0057] Example 4 This embodiment describes in detail the specific process of the power management controller executing the reverse power supply control method.

[0058] Step A: Continuously monitor the input voltage of the main power interface.

[0059] Step B: When the input voltage of the main power interface is below 10 volts for 10 milliseconds, start the reverse power supply mode.

[0060] Step C: Detect the backup power interface. If the backup power interface voltage is higher than 10 volts, switch to backup power supply. If there is no backup power or the backup power voltage is lower than 10 volts, send a reverse power supply request frame to each powered device.

[0061] Step D: When at least one powered device returns a reverse power supply confirmation frame, the reverse power supply circuit of the powered device is enabled, and the bidirectional power converter is configured in reverse mode so that the powered device provides sustaining power to the power supply device.

[0062] Step E: When the input voltage of the main power interface recovers to above 10 volts and remains above 10 volts for 50 milliseconds, switch back to forward mode, restore main power supply, and send a reverse power supply termination command to the powered device.

[0063] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A vehicle-mounted PoDL power supply system supporting bidirectional power supply and dynamic power scheduling, characterized in that, It includes a power supply device and at least one powered device connected to the power supply device via an Ethernet cable; The power supply equipment includes: Main power interface, used to connect to an external main power supply; Backup power interface, used to connect a backup power source; A bidirectional power converter, whose input terminals are electrically connected to the main power interface and the backup power interface respectively, and whose output terminals are electrically connected to multiple power supply ports, is configured as an isolated DC-DC conversion circuit and can switch between forward and reverse modes. A power management controller, connected to the bidirectional power converter, is used to control the switching of the bidirectional power converter's operating mode and to perform dynamic power scheduling and reverse power supply control. A port monitoring module is set up one-to-one with each power supply port to monitor the electrical parameters of each power supply port and report them to the power management controller; A data exchange module, connected to the plurality of power supply ports and the power management controller, is used to transmit standard Ethernet data frames and power scheduling command frames; The memory is connected to the power management controller; The power receiving device includes: A power extraction circuit for extracting power through the Ethernet cable; The power receiving device controller is used to interact with the power supply device via a handshake protocol and parse the power scheduling instruction frame; A DC-DC converter converts the input voltage into the internal operating voltage of the powered device. A reverse power supply circuit is used to feed the power of the powered device to the Ethernet cable in reverse power supply mode.

2. The vehicle-mounted PoDL power supply system according to claim 1, characterized in that, The bidirectional power converter adopts a full-bridge isolated DC-DC converter topology, including: The first full-bridge circuit has its input terminal connected to the main power interface and / or the backup power interface; The second full-bridge circuit has its output connected to the plurality of power supply ports; A high-frequency transformer, wherein the primary winding is connected to the first full-bridge circuit and the secondary winding is connected to the second full-bridge circuit; A resonant inductor is connected in series in the primary winding circuit of the high-frequency transformer; A resonant capacitor is connected in parallel across the primary winding of the high-frequency transformer.

3. The vehicle-mounted PoDL power supply system according to claim 1, characterized in that, Performing the dynamic power scheduling includes the following steps: Step S1: System initialization, initialize the total power pool; Step S2: When a powered device is connected to the power supply port, the power management controller obtains the maximum power requirement of the powered device; Step S3: If the maximum power demand is less than or equal to the current remaining power pool, then allocate power to the power supply port and turn on the power supply; If the value is greater than the threshold, a priority arbitration mechanism will be initiated. Step S4: The priority arbitration mechanism includes: the power management controller selects the powered port according to the preset priority, requests it to reduce the power allocation, the released power is recovered to the power pool, and step S3 is re-executed; Step S5: During the power supply process, the power allocation of each port is dynamically adjusted according to the real-time power reported by the port monitoring module, and the power surplus is recovered to the power pool, or additional power is allocated from the power pool.

4. The vehicle-mounted PoDL power supply system according to claim 1, characterized in that, Performing the reverse power supply control includes the following steps: Step A: The power management controller continuously monitors the input voltage of the main power interface; Step B: When the input voltage of the main power interface is lower than the first voltage threshold and the duration exceeds the first time threshold, the reverse power supply mode is activated; Step C: Detect the backup power interface. If there is no backup power or the backup power voltage is invalid, send a reverse power supply request frame to each powered device through the data exchange module. Step D: When a reverse power supply confirmation frame is received from at least one powered device, the bidirectional power converter is controlled to switch to reverse mode and the reverse power supply circuit of the powered device is enabled, so that the powered device supplies power to the power supply device. Step E: When the input voltage of the main power interface recovers to above the second voltage threshold and the duration exceeds the second time threshold, control the bidirectional power converter to switch back to forward mode, restore the main power supply, and send a reverse power supply termination command to the powered device.

5. The vehicle-mounted PoDL power supply system according to claim 4, characterized in that, The first voltage threshold is 10V, and the first time threshold is 10 milliseconds; the second voltage threshold is 10V, and the second time threshold is 50 milliseconds.

6. The vehicle-mounted PoDL power supply system according to any one of claims 1-5, characterized in that, The powered device is a vehicle-mounted camera, vehicle-mounted radar, vehicle-mounted infotainment system, or vehicle-mounted control unit.

7. A power supply device applied to the vehicle-mounted PoDL power supply system of claim 1, characterized in that, The power supply equipment includes the main power interface, the backup power interface, the bidirectional power converter, the power management controller, the port monitoring module, and the data exchange module.

8. A power receiving device applied to the vehicle-mounted PoDL power supply system of claim 1, characterized in that, The power receiving device includes the power extraction circuit, the power receiving device controller, the DC-DC converter, and the reverse power supply circuit.

9. A dynamic power scheduling method for an on-board PoDL power supply system, characterized in that, Performed via the power supply system as described in claim 1, including: Initialize the total power pool; When a new power-receiving device is connected, its maximum power requirement is obtained; If the current remaining power pool capacity meets the demand, power is allocated and power is supplied; if not, according to the preset priority, the low-priority devices that are already powered are requested to reduce their power to release power resources. During equipment operation, the actual power of each port is continuously monitored. Excess power where the difference between the actual power and the allocated power exceeds a first threshold is recycled to the power pool. When the actual power is close to the allocated power, additional power is allocated from the power pool.

10. A reverse power supply control method for an on-board PoDL power supply system, characterized in that, Performed via the power supply system as described in claim 1, including: Monitor the main power supply status of the power supply equipment; When the main power supply fails and there is no available backup power supply, a reverse power supply request is broadcast to the powered devices in the network. Receive confirmation responses from powered devices that support reverse power supply functionality; The power converter inside the power supply equipment is switched to reverse working mode to accept power from the power receiving equipment in order to maintain the operation of the critical functions of the power supply equipment. When the main power supply is restored, switch back to normal power supply mode and notify the powered equipment to stop feeding power.

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