Low-pressure cabin-mounted direct-current power supply device

Abstract

The invention discloses a low-pressure cabin-mounted direct-current power supply device which comprises a sealing structure and a direct-current conversion power supply part, the sealing structure comprises a sealing shell, a switching module, a sealing ring and a standard fastener, and the direct-current conversion power supply part comprises a main control module, a power distribution module, a power module and a heat dissipation module. The switching module and the power module are jointly sealed in the sealed shell, direct-current voltage and communication signals input and output by the switching module are filtered through the EMC module, the filtered input direct-current voltage signals are transmitted to the power distribution module and the power module, the filtered input communication signals are transmitted to the main control module, and the main control module is connected with the power distribution module and the power module. And the output direct-current voltage signal and the communication signal are transmitted to an external load and a communication system. The technology is safe and reliable, and the product performance is excellent; the cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic levitation vehicles, and in particular to a low-pressure cabin-borne direct current power supply device. Background Art

[0002] The environmental conditions inside a maglev vehicle are special, far lower than the standard atmospheric pressure environment. The physical properties, mechanical properties, electrical properties, temperature rise and heat dissipation problems, and sealing product performance of the DC conversion power supply in a low-pressure use environment may all be affected, making the DC conversion power supply unable to work reliably in a low-pressure environment and unable to meet the normal working requirements of the maglev vehicle. At present, the common problems in low-pressure environments such as deformation of the DC conversion power supply structure shell, electrical properties, temperature rise and heat dissipation in a low-pressure environment are solved. Through the use of sealing structures, switching devices, control systems and control methods, the DC conversion power supply can work reliably in a low-pressure environment in the cabin. The existing maglev vehicle technology does not have a DC power supply for low-pressure application environments, and cannot reliably output the electrical performance of the DC power supply device in a low-pressure environment.

[0003] Prior art CN111458170A discloses a comprehensive environmental thermal balance test system for a stand-alone Mars rover product, which studies five aspects of the test system: gas atmosphere, wind speed, pressure, solar radiation, and temperature. It is mainly in the environmental thermal balance test system, without DC power conversion. The system environment is changed by valves, etc., and there is no internal or external switching device. Summary of the invention

[0004] The present invention provides a low-pressure cabin-borne DC power supply device and control method, which is a DC conversion power supply device used in a low-pressure environment of a magnetic levitation vehicle. The internal and external air pressures are isolated by a sealing structure design, a sealing ring, and a cabin-penetrating adapter. The DC power supply device is controlled to communicate with the outside world and output a DC voltage by a control method. In addition, the device has no obvious structural deformation under a large environmental pressure difference, has good heat dissipation performance, and meets the requirements for insulation performance and electrical strength.

[0005] The technical solution adopted by the present invention is a low-pressure cabin-mounted DC power supply device, including a sealing structure and a DC conversion power supply part, the sealing structure includes a sealing shell, a switching module, a sealing ring and standard fasteners, the DC conversion power supply part includes a main control module, a distribution module, a power module and a heat dissipation module, which are sealed together in the sealing shell, the DC voltage and communication signal input and output by the switching module are first filtered by the EMC module, the filtered input DC voltage signal is transmitted to the distribution module and the power module, the filtered input communication signal is transmitted to the main control module, and the output DC voltage signal and communication signal are transmitted to the external load and the communication system.

[0006] Preferably, the main control module adopts a PI control algorithm to control and adjust the duty cycle of the BUCK switch tube in the input voltage of the LLC topology circuit in the power module, and control the output voltage of the DC conversion power supply.

[0007] Preferably, the sealing shell is divided into upper and lower boxes, a sealing ring installation groove is provided at the box flange, a standard fastener is provided on the outer surface of the box, and the sealing shell adopts a thickened profile combined with a rib plate design.

[0008] Preferably, the adapter module adopts a through-cabin structure device to input and output DC voltage signals, and realizes the communication function between the DC power supply device on board the low-pressure cabin and external facilities through a CAN signal.

[0009] Preferably, the inside of the sealed shell is at standard atmospheric pressure, and the outside of the sealed shell is at a low pressure usage environment.

[0010] Preferably, the low-pressure cabin-borne DC power supply device adopts a combination of convection heat dissipation and radiation heat dissipation to dissipate heat, and the sealed shell adopts a graphene coating radiation heat dissipation method.

[0011] Preferably, the power distribution module includes an auxiliary source circuit, a voltage sampling circuit and a current sampling circuit. The auxiliary source circuit provides a DC voltage as the original secondary power supply for the sampling circuit, the control circuit and the drive circuit. The voltage sampling circuit and the current sampling circuit collect electrical signals and output them to the main control module for processing to control the DC voltage change output.

[0012] The beneficial effects of the present invention are as follows: excellent performance: a low-pressure cabin-borne DC power supply device and control method isolates internal and external pressures through a closed structure, and the DC power supply conversion part adopts mature technology under standard atmospheric pressure, the technology is safe and reliable, and the product performance is excellent; low cost: the DC conversion device can work reliably in a low-pressure environment by isolating internal and external pressures through a closed structure, the electronic components are sealed in a standard atmospheric pressure environment, and the selected quality grades are all electronic components working under standard atmospheric pressure, effectively achieving reliable performance at low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The figure is a working block diagram of a low-pressure cabin-mounted power supply device.

[0014] Figure 2 The figure is a principle block diagram of a low-pressure cabin-mounted power supply device. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0016] The main technical problems solved by the low-pressure cabin-mounted DC power supply device and control method of the present invention are as follows: (1) the problem of reliable DC output of DC conversion power supply in low-pressure environment is solved; (2) the problem of pressure difference deformation of closed structure is less than 0.5mm is solved; (3) The leakage of the closed structure per unit time is no more than 3.4×10 -10 KPa sealing problem; (4) Solved the heat dissipation problem in closed space with low external air pressure.

[0017] This patent discloses a low-pressure cabin-mounted DC power supply device and control method. It is a device that realizes reliable operation of the cabin-mounted power supply device in a low-pressure environment through a sealing method and a control method. The low-pressure cabin-mounted DC power supply device realizes internal and external pressure isolation through a closed structure design, a sealing ring, and a cabin-penetrating adapter, and realizes that the power supply module works in a standard atmospheric pressure environment. The DC voltage and communication signal are input and output through a sealed adapter, and the performance indicators of the DC power supply device are reliable.

[0018] like Figure 1 and Figure 2 As shown, a low-pressure cabin-mounted DC power supply device is mainly composed of a sealing structure and a DC conversion power supply, which realizes the DC voltage conversion output of the cabin-mounted DC power supply device under a low-pressure use environment. The sealing structure is mainly composed of a sealing shell, an adapter module, a sealing ring and standard fasteners. The sealed shell is divided into an upper and lower box body, and a sealing ring installation groove is provided at the box body flange. Standard fasteners are provided on the outer surface of the box body to ensure the sealing of the box body. The sealed shell adopts a thickened profile combined with a rib plate design. It has the characteristics of a standard atmospheric pressure inside the sealed structural shell, a low-pressure use environment outside the structural shell, and a small pressure difference deformation. The adapter module is used for a closed mechanism with small leakage. It can ensure the input and output DC conversion voltage under the internal and external pressure difference and transmit CAN communication signals.

[0019] The DC conversion power supply part is mainly composed of the main control module, power distribution module, power module and heat dissipation module, which are sealed together in a sealed structure housing. The DC voltage and communication signal input and output by the adapter module are first filtered by the EMC module, and the filtered input DC voltage signal is transmitted to the power distribution module and the power module, and the filtered input communication signal is transmitted to the main control module, and the output DC voltage signal and communication signal are transmitted to the external load and communication system.

[0020] The input DC voltage signal completes DC voltage sampling and current sampling in the power distribution module, and the sampling results are output to the main control module. The main control module adopts PI control algorithm to control and adjust the duty cycle of the BUCK switch tube in the input voltage of the LLC topology circuit in the power module, and control the output voltage of the DC conversion power supply.

[0021] The DC power supply device on the low-pressure cabin adopts a combination of convection and radiation to dissipate heat. The equipment cabin is at standard atmospheric pressure, and fans are used to enhance convection to balance the heat of the power module. The outside of the cabin is a low-pressure environment with reduced air density, and the sealed structure shell adopts graphene coating radiation to dissipate heat.

[0022] The communication signal is transmitted to the main control module through the adapter module to realize external communication. The main control module, power distribution module and power module cooperate to realize DC voltage conversion. Figure 2 shown.

[0023] The EMC circuit is a filter module, which is mainly composed of filter capacitors and filter inductors. Its main function is to provide input and output filtering functions for the power supply.

[0024] The power module circuit adopts a BUCK+LLC two-stage topology structure to achieve isolated conversion of input and output, realize wide range DC voltage input, and adjustable output DC voltage.

[0025] The auxiliary source circuit in the power distribution module provides DC voltage as the original secondary power supply for the sampling circuit, control circuit and drive circuit. The voltage sampling circuit and current sampling circuit collect electrical signals and output them to the main control module for processing, controlling the DC voltage change output.

[0026] The CAN communication circuit in the main control module completes the reporting and adjustment of power supply voltage and current signals. Output current sampling, current regulation circuit, current regulation setting circuit, and overcurrent protection circuit are used for current closed loop and overcurrent protection. The main function of output voltage sampling, voltage regulation circuit, voltage regulation setting circuit, and overvoltage protection circuit is to protect the power supply from overvoltage. The control circuit is to realize constant voltage and constant current output adjustment, overvoltage and overcurrent protection, etc. of the voltage module.

[0027] After the auxiliary power supply is powered on, the main control module receives the external DC power supply start-up command through CAN, opens the input contactor, and the power module is powered on and in standby mode; after the main control module issues the DC power supply command, it opens the output contactor and the power module works under load. The two groups of power modules are connected by a current sharing bus and exchange data and commands with the main control module through the CAN bus.

[0028] The technical points of the present invention are: 1. A low-pressure cabin-mounted DC power supply device is a DC conversion power supply device used in a low-pressure environment of a magnetic levitation vehicle. The internal and external air pressures are isolated by a sealed structure, and a switching module is used to reliably realize DC voltage conversion.

[0029] 2. The sealing structure of the low-pressure cabin-mounted DC power supply device consists of a sealing box, a switching module, a sealing ring and standard fasteners. A sealing ring installation groove is provided at the box flange, and standard fasteners are provided on the outer surface of the box to isolate the internal and external air pressures. The sealing shell adopts a thickened profile combined with a rib plate design to reduce pressure difference deformation.

[0030] 3. The adapter module adopts a through-cabin structure device with small leakage. It can ensure the input and output DC conversion voltage under the internal and external pressure difference and transmit CAN communication signals.

[0031] 4. The DC power supply device adopts a BUCK+LLC two-stage topology structure to achieve input and output isolation conversion, and realize wide range DC voltage input and output DC voltage.

[0032] 5. The DC power supply device control method adopts PI control algorithm to control and adjust the duty cycle of the BUCK switch tube in the input voltage of the LLC topology circuit in the power module, and control the output voltage of the DC conversion power supply.

[0033] 6. The DC power supply device on the low-pressure cabin adopts a cooling method that combines convection and radiation. The fan is used in the equipment cabin to enhance convection to balance the heat of the power module, and the graphene coating of the sealed structure shell is used outside the cabin to radiate heat.

[0034] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A low pressure cabin onboard DC power supply device, characterized in that: It includes a sealing structure and a DC conversion power supply part. The sealing structure includes a sealing shell, a switching module, a sealing ring and standard fasteners. The DC conversion power supply part includes a main control module, a power distribution module, a power module and a heat dissipation module, which are sealed together in the sealing shell. The DC voltage and communication signal input and output by the switching module are first filtered by the EMC module. The filtered input DC voltage signal is transmitted to the power distribution module and the power module. The filtered input communication signal is transmitted to the main control module. The output DC voltage signal and communication signal are transmitted to the external load and the communication system.

2. A low pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The main control module adopts a PI control algorithm to control and adjust the duty cycle of the BUCK switch tube in the input voltage of the LLC topology circuit in the power module, and control the output voltage of the DC conversion power supply.

3. The low-pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The sealing shell is divided into an upper and lower box body, a sealing ring installation groove is arranged at the box body flange, a standard fastener is arranged on the outer surface of the box body, and the sealing shell adopts a thickened profile combined with a rib plate design.

4. The low pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The adapter module adopts a through-cabin structure device to input and output a DC voltage signal, and realizes the communication function between the DC power supply device on the low-pressure cabin and external facilities through a CAN signal.

5. The low-pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The inside of the sealed shell is at standard atmospheric pressure, and the outside of the sealed shell is at a low-pressure use environment.

6. The low pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The low-pressure cabin-mounted DC power supply device dissipates heat by combining convection heat dissipation and radiation heat dissipation, and the sealed shell dissipates heat by using graphene coating radiation.

7. The low-pressure cabin-mounted DC power supply device according to claim 1, characterized in that: The power distribution module includes an auxiliary source circuit, a voltage sampling circuit and a current sampling circuit. The auxiliary source circuit provides a DC voltage as the original secondary power supply for the sampling circuit, the control circuit and the drive circuit. The voltage sampling circuit and the current sampling circuit collect electrical signals and output them to the main control module for processing, thereby controlling the DC voltage change output.

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