Automatic pressure control system and method for vehicle-mounted waste heat recovery system and vehicle

Abstract

The invention provides an automatic pressure control system and method for a vehicle-mounted waste heat recovery system and a vehicle, and belongs to the technical field of vehicle-mounted waste heat recovery. The operation state of the turbine bypass valve is obtained, if the turbine bypass valve is in the open state, the pressure regulation and control logic mapping table in the turbine open state is called, and the turbine bypass valve opening degree information is obtained; configuring a mapping opening range and a recommended opening value according to the working medium pressure of the heat exchange output end of the flue gas evaporator; detecting whether the opening degree of the turbine bypass valve is within a mapping opening degree range or not; if not, the opening degree of the turbine bypass valve is set to be the recommended opening degree value; and the steps are repeated, waste heat recovery pressure control is executed once every preset duration, and automatic waste heat recovery pressure control is achieved. The waste heat recovery system can perform real-time automatic pressure adjustment along with the vehicle running state in the actual vehicle running process, and efficient and accurate pressure control is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle-mounted waste heat recovery, and in particular relates to an automatic pressure control system, method and vehicle for a vehicle-mounted waste heat recovery system. Background Art

[0002] In the field of transportation, commercial vehicles often use diesel engines as the main power source of the vehicle, which generates a lot of waste heat during operation, such as exhaust waste heat, cooling water waste heat, etc. At present, this waste heat is directly discharged into the environment, which not only wastes energy, but also may cause thermal pollution to the environment.

[0003] In order to effectively utilize this waste heat, the on-board waste heat recovery system came into being. The on-board waste heat recovery system is a technology that can effectively improve the energy efficiency of vehicles. The on-board waste heat recovery system utilizes the waste heat generated by the engine and other components and converts it into usable energy. This technology not only helps to save energy and reduce emissions, but also improves the overall performance of the vehicle.

[0004] However, traditional waste heat recovery systems often have problems such as low efficiency, poor system stability, and complex operation. In particular, under different working conditions, changes in the internal pressure of the system will directly affect the efficiency of waste heat recovery. If the pressure is too high or too low, it will lead to a decrease in waste heat recovery efficiency and may even damage the system. Summary of the invention

[0005] The present invention provides an automatic pressure control system for a vehicle-mounted waste heat recovery system. The system is suitable for waste heat recovery of the entire vehicle and can automatically adjust the system pressure in real time to keep the pressure in a high-efficiency working range, thereby meeting the automatic pressure control requirements for vehicle-mounted waste heat recovery.

[0006] The system regenerator, the cold end input end of the regenerator is connected to the liquid storage tank through a working fluid pump; the cold end output end of the regenerator is connected to the heat exchange input end of the preheater; The heat exchange output end of the preheater is connected to the heat exchange input end of the flue gas evaporator, and the heat exchange output end of the flue gas evaporator is respectively connected to the hot end input end of the regenerator and the input end of the turbine expander; the hot end output end of the regenerator is connected to the liquid storage tank through the condenser; The output end of the turbo expander is connected to the hot end input end of the regenerator; The heat absorption output end of the preheater is connected to the cylinder jacket water input end of the diesel engine, and the cylinder jacket water output end of the diesel engine is connected to the heat absorption input end of the preheater; The exhaust end of the diesel engine is connected to a turbocharger, which is also connected to a flue gas evaporator.

[0007] It should be further explained that a turbine bypass valve is provided between the heat exchange output end of the flue gas evaporator and the hot end input end of the regenerator; An electric control valve is arranged between the output end of the turbine expander and the hot end input end of the regenerator.

[0008] It should be further explained that a pressure sensor and a temperature sensor are provided on one side of the input end of the turbo expander.

[0009] According to another embodiment of the present application, a method for automatically controlling pressure of a vehicle-mounted waste heat recovery system is provided, the method comprising: S101: Obtaining working fluid pressure information P at a heat exchange output end of a flue gas evaporator; S102: Acquire the operating state of the turbine bypass valve. If it is in the open state, retrieve the pressure control logic mapping table in the turbine open state to obtain the turbine bypass valve opening information K; S103: configuring a mapping opening range and a recommended opening value according to the working fluid pressure at the heat exchange output end of the flue gas evaporator; S104: Detecting whether the opening of the turbine bypass valve is within a mapped opening range; If it is, end this control; If not, set the turbine bypass valve opening to the recommended opening value; S105: At this point, one waste heat recovery pressure control is completed, and in this cycle, the waste heat recovery pressure control is executed once every preset time period to achieve automatic waste heat recovery pressure control.

[0010] It should be further explained that step S102 also includes: When the vehicle is moving and the operating conditions of the turbine expander are met, the turbine expander is turned on and performs work to generate electricity.

[0011] It should be further explained that, in the method, the working medium pressure P at the heat exchange output end of the flue gas evaporator and the opening K of the turbine electric bypass valve are configured in a one-to-one correspondence to form a pressure control logic mapping table.

[0012] It should be further explained that the pressure control logic mapping table includes: P≤1000kPa, K=0%; 1000kPa<P≤1100kPa, K≤20%; 1100kPa<P≤1200kPa, 15%≤K≤30%; P>1200kPa, K=0%.

[0013] It should be further explained that the method further includes: when the turbine bypass valve is in the non-open state, calling the pressure control logic mapping table in the turbine closed state; The pressure control logic mapping table in the turbine off state includes: P≤150kPa, 24%≤K≤34%; 150kPa<P≤250kPa, 28%≤K≤38%; 250kPa<P≤400kPa, 32%≤K≤42%; 400kPa<P≤550kPa, 36%≤K≤46%; 550kPa<P≤700kPa, 40%≤K≤50%; 700kPa<P≤850kPa, 44%≤K≤54%; P>850kPa, K=54%.

[0014] It should be further explained that S103 also includes: if the turbine bypass valve is in the open state, then according to the pressure control logic mapping table in the turbine open state, the corresponding turbine bypass valve opening range is selected, and the recommended opening value of the turbine bypass valve is the maximum value of the turbine bypass valve opening information K under the range of the working medium pressure information P at the heat exchange output end of the flue gas evaporator; If the turbine bypass valve is in the closed state, the corresponding turbine bypass valve opening range is selected according to the pressure control logic mapping table when the turbine is in the closed state. The recommended opening value of the turbine bypass valve is the minimum value of the turbine bypass valve opening information K within the range of the working fluid pressure information P at the heat exchange output end of the flue gas evaporator plus 6%.

[0015] According to another embodiment of the present application, a vehicle is also provided, comprising the on-board waste heat recovery system pressure automatic control system.

[0016] It can be seen from the above technical solutions that the present invention has the following advantages: In the vehicle-mounted waste heat recovery system pressure automatic control system provided by the present application, the waste heat of the diesel engine cylinder jacket water is used to preheat the working fluid output from the cold end of the regenerator. The working fluid temperature entering the flue gas evaporator can be increased, thereby improving the overall heat exchange efficiency of the system. The flue gas evaporator can also heat the working fluid output by the preheater based on the high-temperature flue gas in the diesel engine exhaust, causing it to evaporate and reach a high temperature and high pressure state. The waste heat in the diesel engine exhaust is converted into the internal energy of the working fluid, thereby improving the heat energy recovery efficiency of the system.

[0017] In the vehicle-mounted waste heat recovery system pressure automatic control system, the working fluid pressure and temperature at the input end of the turbine expander can be monitored in real time, providing accurate parameter basis for the automatic control and protection of the system. The working fluid flow rate, bypass valve opening, etc. can be automatically adjusted to ensure stable operation of the system. The regenerator can be used to recover the heat carried by the high-temperature working fluid discharged from the turbine expander and the flue gas evaporator, and heat the low-temperature working fluid from the liquid storage tank. Improve the thermal efficiency of the system, reduce heat waste through the recovery and reuse of heat energy, and make the energy utilization rate of the entire system higher.

[0018] The system can also enable the waste heat recovery system to automatically adjust the pressure in real time according to the vehicle's operating status during actual vehicle operation, so that the system pressure is maintained within the target design range, achieving efficient and accurate pressure control. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the automatic pressure control system of the vehicle waste heat recovery system; Figure 2 This is a flow chart of the automatic pressure control method of the vehicle-mounted waste heat recovery system; Figure 3 The present invention is a flow chart of an embodiment of a method for automatically controlling pressure of a vehicle-mounted waste heat recovery system.

[0021] Description of reference numerals: 1-Liquid storage tank; 2-Working fluid pump; 3-Regenerator; 4-Preheater; 5-Cylinder jacket water; 6-Flue gas evaporator; 7-Diesel engine; 8-Exhaust pipeline; 10-Turbocharger; 11-Turbine bypass valve; 12-Pressure sensor; 13-Temperature sensor; 14-Turbine expander; 15-Condenser. DETAILED DESCRIPTION

[0022] The vehicle-mounted waste heat recovery system pressure automatic control system involved in this application obtains relevant parameters such as working fluid pressure information, and then adjusts it according to the pressure control logic mapping table to give the opening instruction of the turbine bypass valve, so as to maintain the system pressure within the target design range, thereby achieving the purpose of precise pressure control.

[0023] The following describes the specific implementation of the vehicle waste heat recovery system pressure automatic control system. For the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are provided to facilitate a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application can also be implemented in other embodiments without these specific details.

[0024] When describing the vehicle-mounted waste heat recovery system pressure automatic control system, the application uses the term "including" to indicate the existence of the described features, entities, steps, operations, elements and / or components, but does not exclude the existence or addition of one or more other features, entities, steps, operations, elements, components and / or their collections. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0025] The "one or more" mentioned in this application refers to one, two or more than two, and the "multiple" mentioned in this application refers to two or more. In the description of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B. The "and / or" in this article is just a way to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0026] The phrases such as "one embodiment" or "some embodiments" described in the present application mean that the specific features, structures or characteristics described in the embodiment are included in one or more embodiments of the present application. Therefore, the phrases such as "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments" etc. that appear in different places in the present application do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways.

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1 The figure shows a schematic diagram of an automatic pressure control system for a vehicle-mounted waste heat recovery system in a specific embodiment. The system includes: a regenerator 3; the cold end input end of the regenerator 3 is connected to the liquid storage tank 1 through a working fluid pump 2. The liquid storage tank 1 stores liquid working fluid and serves as the starting point and end point of the working fluid circulation. Ensure that the system has a stable supply of working fluid, and collect the liquid working fluid condensed by the condenser 15 for recycling again. The working fluid pump 2 can pressurize the liquid working fluid in the liquid storage tank 1 and transport it to the cold end input end of the regenerator 3. The working fluid pump 2 can provide sufficient pressure to enable the liquid working fluid to circulate in the system to complete the process of absorbing, transferring and releasing heat energy.

[0029] The cold end output of the regenerator 3 of this embodiment is connected to the heat exchange input of the preheater 4. The heat exchange output of the preheater 4 is connected to the heat exchange input of the flue gas evaporator 6, and the heat exchange output of the flue gas evaporator 6 is connected to the hot end input of the regenerator 3 and the input of the turbine expander 14 respectively.

[0030] In some embodiments, the preheater 4 uses the waste heat of the cylinder jacket water of the diesel engine 7 to preheat the working fluid output from the cold end of the regenerator 3. The temperature of the working fluid entering the flue gas evaporator 6 can be increased, thereby improving the overall heat exchange efficiency of the system. The flue gas evaporator 6 can also heat the working fluid output by the preheater 4 based on the high-temperature flue gas in the exhaust of the diesel engine 7, so that it evaporates and reaches a high temperature and high pressure state. The waste heat in the diesel engine exhaust is converted into the internal energy of the working fluid, thereby improving the heat energy recovery efficiency of the system.

[0031] In this embodiment, a pressure sensor 12 and a temperature sensor 13 are provided on one side of the input end of the turbo expander 14. The pressure sensor 12 and the temperature sensor 13 can monitor the working fluid pressure and temperature at the input end of the turbo expander 14 in real time, and provide accurate parameter basis for automatic control and protection of the system. Through these parameters, the control system can automatically adjust the working fluid flow rate, bypass valve opening, etc., to ensure safe and efficient operation of the system.

[0032] The hot end output end of the regenerator 3 of this embodiment is connected to the liquid storage tank 1 through the condenser 15; the output end of the turbine expander 14 is connected to the hot end input end of the regenerator 3.

[0033] The turbine expander 14 of this embodiment expands the high-temperature and high-pressure working fluid to do work, outputs mechanical energy or electrical energy, and reduces the temperature and pressure of the working fluid to prepare for the subsequent heat exchange process.

[0034] In this embodiment, the regenerator 3 can be used to recover the heat carried by the high-temperature working fluid discharged from the turbine expander 14 and the flue gas evaporator 6, and heat the low-temperature working fluid from the liquid storage tank 1. The thermal efficiency of the system is improved, and the waste of heat is reduced by recycling and reusing heat energy, so that the energy utilization rate of the entire system is higher.

[0035] The heat absorption output end of the preheater 4 of this embodiment is connected to the cylinder water input end of the diesel engine 7, and the cylinder water output end of the diesel engine 7 is connected to the heat absorption input end of the preheater 4; the exhaust end of the diesel engine 7 is connected to the turbocharger 10 through the exhaust pipe 8, and the turbocharger 10 is also connected to the flue gas evaporator 6, which can transfer the high-temperature waste heat in the diesel engine exhaust to the working medium, thereby realizing the recovery and utilization of the waste heat.

[0036] In some embodiments, the condenser 15 can condense the low-temperature and low-pressure working fluid output from the hot end of the turbine expander 14 or the regenerator 3 into a liquid state, recover the waste heat in the working fluid, and condense the working fluid into a liquid state so as to be stored in the liquid storage tank 1 again, thus completing the circulation of the working fluid.

[0037] In some specific embodiments, the connection between the preheater 4 and the cylinder jacket water of the diesel engine 7 can utilize the waste heat of the cylinder jacket water of the diesel engine to preheat the working fluid and improve the thermal efficiency of the system.

[0038] In some embodiments, a turbine bypass valve 11 is provided between the heat exchange output end of the flue gas evaporator 6 and the hot end input end of the regenerator 3; the turbine bypass valve 11 can open the bypass valve to adjust the system pressure and protect the safety of the equipment under certain working conditions, such as when the turbine expander 14 is underloaded or the system pressure is too high. An electric control valve is provided between the output end of the turbine expander 14 and the hot end input end of the regenerator 3. The electric control valve can automatically adjust the working fluid flow at the output end of the turbine expander 14 according to the signals of the system pressure and temperature sensors to maintain stable operation of the system.

[0039] The following is an embodiment of the vehicle-mounted waste heat recovery system pressure automatic control method provided in the embodiment of the present disclosure. This method and the vehicle-mounted waste heat recovery system pressure automatic control system of the above-mentioned embodiments belong to the same inventive concept. For details not described in detail in the embodiment of the vehicle-mounted waste heat recovery system pressure automatic control method, please refer to the above-mentioned vehicle-mounted waste heat recovery system pressure automatic control system embodiment.

[0040] like Figure 2 As shown, the method includes: S101: Obtaining working fluid pressure information P at the heat exchange output end of the flue gas evaporator.

[0041] In some embodiments, this is achieved by installing a pressure sensor at the heat exchange output end of the flue gas evaporator. In this way, the pressure information P of the working fluid at this position can be monitored and output in real time for subsequent control logic judgment. It also enables the system to understand the efficiency of the current waste heat recovery process and the flow state of the working fluid in the system, providing a basis for subsequent control decisions.

[0042] S102: The operating state of the turbine bypass valve is obtained. If the operating state of the turbine bypass valve is open, a pressure control logic mapping table in the turbine open state is retrieved to obtain the opening information K of the turbine bypass valve.

[0043] In this embodiment, when the vehicle is moving and the operating conditions of the turbine expander are met, the turbine expander is turned on and performs work to generate electricity.

[0044] In this embodiment, when it is determined that the turbine bypass valve is in an open state, the system will calculate appropriate turbine bypass valve opening information K according to a preset pressure control logic mapping table and information such as the current engine load and speed.

[0045] In this way, the opening state of the turbine bypass valve directly affects the flow path and pressure distribution of the working fluid in the system. By obtaining the operating state of the turbine bypass valve and adjusting its opening accordingly, the system can flexibly respond to the waste heat recovery needs under different working conditions, optimize system performance, and ensure the efficiency and stability of the waste heat recovery process.

[0046] S103: configuring a mapping opening range and a recommended opening value according to the working fluid pressure at the heat exchange output end of the flue gas evaporator.

[0047] This embodiment can preset a pressure-opening mapping relationship. According to the working medium pressure P at the heat exchange output end of the flue gas evaporator, combined with the design requirements and control strategy of the system, the reasonable opening range of the turbine bypass valve and the recommended opening value under the current working conditions are calculated.

[0048] This can provide clear guidance for the subsequent turbine bypass valve opening adjustment, ensuring that the turbine bypass valve opening adjustment meets the requirements for waste heat recovery efficiency.

[0049] S104: Detecting whether the opening of the turbine bypass valve is within a mapped opening range; If it is, end this control; If not, set the turbine bypass valve opening to the recommended opening value.

[0050] This embodiment detects the actual opening of the turbine bypass valve in real time through the valve position sensor or the state monitoring function inside the control system, and compares it with the mapped opening range configured in step S103. By comparing the actual opening with the mapped opening range, the system can timely discover and correct possible opening deviations, ensuring that the opening of the turbine bypass valve is always within the optimal or acceptable range.

[0051] S105: At this point, one waste heat recovery pressure control is completed, and in this cycle, the waste heat recovery pressure control is executed once every preset time period to achieve automatic waste heat recovery pressure control.

[0052] For this embodiment, when it is detected that the opening of the turbine bypass valve is within the mapped opening range, it can be defined as the current opening is appropriate and does not need to be adjusted, and the control process ends.

[0053] If the opening is not within the mapped opening range, the opening of the turbine bypass valve is automatically adjusted to the recommended opening value to achieve automatic pressure control.

[0054] It can be seen that the method of this embodiment can ensure that the pressure of the waste heat recovery process is always kept within the optimal or acceptable range by adjusting the opening of the turbine bypass valve according to the comparison result, thereby improving the stability of the system and the waste heat recovery efficiency. Accurate control of the system pressure is achieved to ensure the stable operation of the system.

[0055] Furthermore, as a refinement and expansion of the specific implementation methods of the above-mentioned embodiment, in order to fully illustrate the specific implementation process in this embodiment, the method uses a pressure control logic mapping table to call up the turbine bypass valve opening range according to the system pressure level, and gives an electric bypass valve opening instruction through the controller to maintain the system pressure within the target design range, thereby achieving the purpose of automatic and precise pressure control.

[0056] like Figure 3 As shown, the vehicle-mounted waste heat recovery system pressure automatic control method also includes the following steps: Step S201, obtaining the measured values ​​of key parameters of the waste heat recovery system through a pressure sensor.

[0057] In this embodiment, the pressure sensor is arranged between the flue gas evaporator and the high-speed turbine expander for heat exchange with the engine exhaust. The key parameter measurement values ​​of the waste heat recovery system include the flue gas evaporator outlet working medium pressure P and the turbine electric bypass valve opening K.

[0058] Step S202, checking the turbine on state, if the turbine is on, calling the pressure control logic mapping table in the turbine on state, if the turbine is not on, calling the pressure control logic mapping table in the turbine off state.

[0059] In this embodiment, checking the turbine opening state includes the turbine opening state and the turbine closing state.

[0060] The turbine on state can be defined as S_tu = 1. The turbine off state can be defined as S_tu = 0.

[0061] When the vehicle starts and stops, the expander inlet temperature and pressure are too high or too low to meet the turbine start-up conditions. At this time, the turbine is in the closed state, and the turbine bypass valve is opened moderately to ensure normal operation of the system. When the vehicle is driving and the waste heat recovery system status meets the turbine expander operating conditions, the turbine is turned on and generates power.

[0062] The pressure control logic mapping table of this embodiment is a one-to-one correspondence between the working fluid pressure P at the flue gas evaporator outlet and the turbine electric bypass valve opening K. The pressure control logic mapping table can be defined according to different heat source waste heat recovery systems and working fluid properties.

[0063] In one embodiment of the present application, the setting method of the pressure control logic mapping table when the turbine is turned on is: P≤1000kPa, K=0%; 1000kPa<P≤1100kPa, K≤20%; 1100kPa<P≤1200kPa, 15%≤K≤30%; P>1200kPa, K=0%.

[0064] How to set the pressure control logic mapping table when the turbine is closed: P≤150kPa, 24%≤K≤34%; 150kPa<P≤250kPa, 28%≤K≤38%; 250kPa<P≤400kPa, 32%≤K≤42%; 400kPa<P≤550kPa, 36%≤K≤46%; 550kPa<P≤700kPa, 40%≤K≤50%; 700kPa<P≤850kPa, 44%≤K≤54%; P>850kPa, K=54%.

[0065] Step S203, selecting and mapping the turbine bypass valve opening range and the recommended opening value according to the working fluid pressure at the evaporator outlet.

[0066] In one embodiment of the present application, if the turbine is turned on, the corresponding turbine bypass valve opening range is selected according to the range of the working fluid pressure P at the evaporator outlet and the pressure control logic mapping table when the turbine is turned on. The recommended opening value of the turbine bypass valve is the maximum value of the K range under the corresponding P range.

[0067] Similarly, if the turbine is closed, the corresponding turbine bypass valve opening range is selected based on the range of the working fluid pressure P at the evaporator outlet and the pressure control logic mapping table when the turbine is closed. The recommended opening value of the turbine bypass valve is the minimum value of the K range under the corresponding P range plus 6%.

[0068] Step S204, checking whether the opening of the turbine bypass valve is within the mapped opening range, if so, ending the current control, if not, setting the opening of the turbine bypass valve to the recommended opening value.

[0069] In one embodiment of the present invention, the time for adjusting the opening of the turbine bypass valve to the recommended value is 2 seconds.

[0070] At this point, the pressure control of the waste heat recovery system is completed once, and this cycle is executed every 4 seconds. Since the waste heat recovery system has large thermal inertia and followability, it does not require too frequent pressure adjustment, so the measurement frequency is 1 second / time, and the pressure control is 4 seconds / time. The real-time automatic pressure control of the vehicle-mounted waste heat recovery system is completed.

[0071] It can be seen that compared with the prior art, the vehicle-mounted waste heat recovery system pressure automatic control method of this embodiment can enable the waste heat recovery system to automatically adjust the pressure in real time according to the vehicle operation state during the actual operation of the vehicle, so that the system pressure is maintained within the target design range, and efficient and accurate pressure control is achieved. In addition, the present invention has been implemented and verified on the whole vehicle, and the feasibility of the method has been determined, and it has a wide range of application prospects.

[0072] The present application also provides a vehicle, specifically including an automatic pressure control system for a vehicle-mounted waste heat recovery system.

[0073] The vehicle of the present application can be combined with the units and algorithm steps of each example described in the embodiments disclosed herein, and can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0074] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or it can be an electrical, mechanical or other form of connection.

[0075] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An automatic pressure control system for a vehicle-mounted waste heat recovery system, characterized in that: include: A regenerator (3), wherein a cold end input end of the regenerator (3) is connected to a liquid storage tank (1) via a working fluid pump (2); and a cold end output end of the regenerator (3) is connected to a heat exchange input end of a preheater (4); The heat exchange output end of the preheater (4) is connected to the heat exchange input end of the flue gas evaporator (6), and the heat exchange output end of the flue gas evaporator (6) is respectively connected to the hot end input end of the regenerator (3) and the input end of the turbine expander (14); the hot end output end of the regenerator (3) is connected to the liquid storage tank (1) through the condenser (15); The output end of the turbine expander (14) is connected to the hot end input end of the regenerator (3); The heat absorption output end of the preheater (4) is connected to the cylinder jacket water input end of the diesel engine (7), and the cylinder jacket water output end of the diesel engine (7) is connected to the heat absorption input end of the preheater (4); The exhaust end of the diesel engine (7) is connected to the turbocharger (10), and the turbocharger (10) is also connected to the flue gas evaporator (6).

2. The vehicle-mounted waste heat recovery system pressure automatic control system according to claim 1, characterized in that: A turbine bypass valve (11) is provided between the heat exchange output end of the flue gas evaporator (6) and the hot end input end of the regenerator (3); An electrically controlled valve is provided between the output end of the turbine expander (14) and the hot end input end of the regenerator (3).

3. The vehicle-mounted waste heat recovery system pressure automatic control system according to claim 1, characterized in that: A pressure sensor (12) and a temperature sensor (13) are provided on one side of the input end of the turbo expander (14).

4. A method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system, characterized in that: The method is implemented based on the vehicle-mounted waste heat recovery system pressure automatic control system according to any one of claims 1 to 3; Methods include: S101: Obtaining working fluid pressure information P at a heat exchange output end of a flue gas evaporator; S102: Acquire the operating state of the turbine bypass valve. If it is in the open state, retrieve the pressure control logic mapping table in the turbine open state to obtain the turbine bypass valve opening information K; S103: configuring a mapping opening range and a recommended opening value according to the working fluid pressure at the heat exchange output end of the flue gas evaporator; S104: Detecting whether the opening of the turbine bypass valve is within the mapped opening range; If it is, end this control; If not, set the turbine bypass valve opening to the recommended opening value; S105: At this point, one waste heat recovery pressure control is completed, and in this cycle, the waste heat recovery pressure control is executed once every preset time period to achieve automatic waste heat recovery pressure control.

5. The method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system according to claim 4, characterized in that: Step S102 also includes: When the vehicle is moving and the operating conditions of the turbine expander are met, the turbine expander is turned on and performs work to generate electricity.

6. The method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system according to claim 4, characterized in that: In the method, the working medium pressure P at the heat exchange output end of the flue gas evaporator and the opening K of the turbine electric bypass valve are configured as a one-to-one correspondence to form a pressure control logic mapping table.

7. The method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system according to claim 6, characterized in that: The pressure control logic mapping table includes: P≤1000kPa, K=0%; 1000kPa<P≤1100kPa, K≤20%; 1100kPa<P≤1200kPa, 15%≤K≤30%; P>1200kPa, K=0%.

8. The method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system according to claim 4, characterized in that: The method further includes: when the turbine bypass valve is in an operating state of not being opened, retrieving a pressure control logic mapping table in a turbine closed state; The pressure control logic mapping table in the turbine off state includes: P≤150kPa, 24%≤K≤34%; 150kPa<P≤250kPa, 28%≤K≤38%; 250kPa<P≤400kPa, 32%≤K≤42%; 400kPa<P≤550kPa, 36%≤K≤46%; 550kPa<P≤700kPa, 40%≤K≤50%; 700kPa<P≤850kPa, 44%≤K≤54%; P>850kPa, K=54%.

9. The method for automatically controlling the pressure of a vehicle-mounted waste heat recovery system according to claim 4, characterized in that: S103 also includes: If the turbine bypass valve is in the open state, the corresponding turbine bypass valve opening range is selected according to the pressure control logic mapping table in the turbine open state. The recommended opening value of the turbine bypass valve is the maximum value of the turbine bypass valve opening information K under the range of the working medium pressure information P at the heat exchange output end of the flue gas evaporator; If the turbine bypass valve is in the closed state, the corresponding turbine bypass valve opening range is selected according to the pressure control logic mapping table when the turbine is in the closed state. The recommended opening value of the turbine bypass valve is the minimum value of the turbine bypass valve opening information K within the range of the working fluid pressure information P at the heat exchange output end of the flue gas evaporator plus 6%.

10. A vehicle, characterized in that: It comprises an automatic pressure control system for a vehicle-mounted waste heat recovery system as claimed in any one of claims 1 to 3.

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