Vehicle-mounted waste heat recovery system and control method and control device thereof

Abstract

The invention relates to the technical field of vehicles, and provides a vehicle-mounted waste heat recovery system and a control method and device thereof. The vehicle-mounted waste heat recovery system comprises a liquid storage device, a working medium pump, a heat regenerator, a preheater, a flue gas evaporator, an expansion machine and a condenser which are sequentially communicated through a working medium pipeline. A cylinder sleeve water pipeline of an engine of the vehicle flows through the preheater and heats the preheater, and an exhaust pipeline of the engine is connected with a flue gas inlet and a flue gas outlet of the flue gas evaporator and heats the flue gas inlet and the flue gas outlet of the flue gas evaporator; the two ends of the expansion machine are connected with a bypass pipeline in parallel, a bypass valve is arranged on the bypass pipeline, an inlet and an outlet of the expansion valve are provided with a first valve and a second valve respectively, and an inlet and an outlet of the working medium pump are provided with a third valve and a fourth valve respectively. According to the vehicle-mounted waste heat recovery system and the control method and the control device thereof, the waste heat recovery system can be adaptively adjusted along with the running state of the vehicle in the actual running process of the vehicle, so that the system is in a designed working condition point during starting, stopping and running.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a vehicle-mounted waste heat recovery system and a control method and a control device thereof. Background Art

[0002] Most of the calorific value of diesel engine fuel combustion is converted into output work through the expansion of gas in the cylinder to push the piston to reciprocate and the crankshaft to rotate, while the rest of the energy, except for overcoming friction, is lost through the cylinder jacket water, exhaust, supercharged air cooling water and oil coolant. Waste heat recovery technology recovers the heat from the above waste heat sources and converts it into useful work output, thereby improving the effective thermal efficiency of the diesel engine, improving fuel energy utilization and reducing carbon dioxide emissions. Waste heat recovery technology has different principle and structural systems, and among them, the organic Rankine cycle system, which mainly includes four major components: expander, evaporator, condenser and working fluid pump, has high heat-to-work conversion efficiency and relatively mature and reliable structural components. It is the current main research direction and the preferred choice for vehicle-mounted waste heat recovery systems.

[0003] However, at present, the waste heat recovery system is more about laboratory-level system structure design and operation method research. Through experimental tests and performance analysis of simulated engine heat sources and cold sources, the waste heat recovery system is further optimized to maximize its effective output power. Its system operation mode and working method are determined according to the steady-state experimental point, and steady-state data analysis is performed on the experimental results of system performance under different engine operating points. The on-board waste heat recovery system is actually in a complex and changing state, and its vehicle operation state changes all the time according to the actual road conditions. Since the waste heat recovery system recovers heat sources by connecting to the engine cylinder jacket water circuit and exhaust circuit, its system state is affected by the vehicle's operating conditions. Based on this, having a mature and stable system working method is of great significance to the on-board waste heat recovery system, and it also plays a positive role in the application scope and technical promotion of subsequent waste heat recovery technology. Summary of the invention

[0004] In view of the problem that the working method of the vehicle-mounted waste heat recovery system in the prior art is immature and imperfect, the present invention provides a vehicle-mounted waste heat recovery system and a control method and a control device thereof. The present invention mainly focuses on a single-machine waste heat recovery system based on an organic Rankine cycle, so that the waste heat recovery system can be adjusted adaptively according to the operating status of the vehicle during the actual operation of the vehicle, so that the system is at the designed operating point when starting and stopping and running.

[0005] According to the first aspect of the present invention, the vehicle-mounted waste heat recovery system includes a liquid storage device, a working fluid pump, a regenerator, a preheater, a flue gas evaporator, an expander and a condenser which are sequentially connected through a working fluid pipeline; The cylinder water pipeline of the vehicle engine flows through the preheater and heats it, and the exhaust pipeline of the engine is connected to the smoke inlet and the smoke outlet of the smoke evaporator and heats them; A bypass pipe is connected in parallel at both ends of the expander, a bypass valve is arranged on the bypass pipe, a first valve and a second valve are arranged at the inlet and outlet of the expansion valve respectively, and a third valve and a fourth valve are arranged at the inlet and outlet of the working fluid pump respectively.

[0006] According to a second embodiment of the present invention, a control method of a vehicle-mounted waste heat recovery system based on the first embodiment of the present invention includes: Get the current working stage of the vehicle; According to the vehicle working stage, the working state and working parameters of the vehicle-mounted waste heat recovery system are controlled and adjusted.

[0007] According to an embodiment of the present invention, the step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically includes: When the vehicle is currently in a shutdown stage or an idling stage, the first valve, the second valve, the third valve, the fourth valve and the bypass valve in the on-board waste heat recovery system are controlled to be closed so that the on-board waste heat recovery system is shut down.

[0008] According to an embodiment of the present invention, the step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically further includes: When the vehicle is currently in a starting stage, controlling the third valve, the fourth valve and the bypass valve to open, so that the on-board waste heat recovery system operates; When it is determined that the on-board waste heat recovery system is running, an inlet working fluid parameter at the inlet of the expander is obtained, and the opening of the bypass valve and / or the speed of the working fluid pump are controlled and adjusted according to the inlet working fluid parameter.

[0009] According to one embodiment of the present invention, the inlet working fluid parameters include inlet working fluid temperature and inlet working fluid pressure, and the step of controlling and adjusting the opening of the bypass valve and / or the speed of the working fluid pump according to the inlet working fluid parameters specifically includes: According to the comparison result between the inlet working fluid temperature and the set temperature range, controlling and adjusting the speed of the working fluid pump so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

[0010] According to an embodiment of the present invention, the step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically further includes: When the vehicle completes the starting phase and enters the running phase, obtaining an inlet working fluid parameter at the inlet of the expander; If it is determined that the inlet working fluid parameter meets the set parameter condition, the first valve and the second valve are controlled to be opened to enable the expander to operate, and the bypass valve is controlled to be closed or reduced to a first set opening.

[0011] According to one embodiment of the present invention, the step of controlling the first valve and the second valve to open so that the expander operates, and controlling the bypass valve to close, specifically includes: Controlling the second valve to open to a maximum opening; While opening and controlling the opening of the first valve to gradually increase, the opening of the bypass valve is controlled to gradually decrease until the first valve reaches the second set opening and the bypass valve is closed or reaches the first set opening.

[0012] According to one embodiment of the present invention, the inlet working fluid parameters include an inlet working fluid temperature and an inlet working fluid pressure, and the set parameter condition is that the inlet working fluid temperature is within a set temperature range and the inlet working fluid pressure is within a set pressure range; Then the control method further includes: During the operation of the expander, monitoring the inlet working fluid temperature and the inlet working fluid pressure of the expander; According to the comparison result between the inlet working fluid temperature and the set temperature range, controlling and adjusting the speed of the working fluid pump so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

[0013] According to an embodiment of the present invention, the step of controlling and adjusting the speed of the working fluid pump according to the comparison result of the inlet working fluid temperature and the set temperature range specifically includes: When the inlet working fluid temperature exceeds the set temperature range, controlling the speed of the working fluid pump to increase; When the inlet working fluid temperature is lower than the set temperature range, controlling the speed of the working fluid pump to decrease; And the step of controlling and adjusting the opening of the bypass valve according to the comparison result of the inlet working fluid pressure and the set pressure range specifically includes: When the inlet working fluid pressure exceeds the set pressure range, controlling the opening of the bypass valve to increase; When the inlet working fluid pressure is lower than the set pressure range, the opening of the bypass valve is controlled to decrease.

[0014] According to a third aspect of the present invention, a control device for a vehicle-mounted waste heat recovery system based on the first aspect of the present invention comprises: An acquisition module, used to acquire the current vehicle working stage of the vehicle; The control module is used to control and adjust the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage.

[0015] The present invention provides a vehicle-mounted waste heat recovery system, which has at least the following advantages compared to the related art.

[0016] (1) Efficient waste heat recovery: The preheater and flue gas evaporator realize dual-channel waste heat recovery of engine cylinder water and exhaust gas, which improves the efficiency of waste heat recovery.

[0017] (2) Flexible control strategy: By using a bypass valve and multiple control valves (such as the first valve, the second valve, the third valve and the fourth valve), the operating mode of the system can be adjusted according to the operating status of the engine.

[0018] (3) Strong adaptability: The system can operate under different vehicle operating conditions and can effectively utilize waste heat whether it is idling or in normal driving.

[0019] (4) Energy saving and emission reduction: By recovering the waste heat generated by the engine and converting it into useful work, fuel consumption is reduced and carbon emissions are lowered.

[0020] (5) Improve fuel economy: The recovered waste heat is used for power generation, which can improve the overall thermal efficiency of the engine and thus improve fuel economy.

[0021] (6) The system is stable and reliable: sophisticated control strategies are used to ensure stable operation of the system under different working conditions, avoiding equipment damage caused by excessive temperature or pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1It is a structural schematic diagram of the vehicle-mounted waste heat recovery system provided by the present invention.

[0024] Figure 2 It is a flow chart of a control method of a vehicle-mounted waste heat recovery system provided by the present invention.

[0025] Figure 3 It is a structural schematic diagram of the control device of the vehicle-mounted waste heat recovery system provided by the present invention.

[0026] Figure 4 It is a structural schematic diagram of the electronic device provided by the present invention.

[0027] Reference numerals: 1. Liquid storage device; 2. Working fluid pump; 3. Regenerator; 4. Preheater; 5. Flue gas evaporator; 6. Expander; 7. Condenser; 8. Engine; 9. Cylinder jacket water pipeline; 10. Working fluid pipeline; 11. Exhaust pipeline; 12. Bypass pipeline; 13. Bypass valve; 14. First valve; 15. Second valve; 16. Third valve; 17. Fourth valve. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.

[0029] A vehicle-mounted waste heat recovery system and a control method and a control device thereof provided by the present invention will be described below with reference to the accompanying drawings.

[0030] like Figure 1 As shown, the vehicle-mounted waste heat recovery system according to the first embodiment of the present invention includes a liquid storage device 1, a working fluid pump 2, a regenerator 3, a preheater 4, a flue gas evaporator 5, an expander 6 and a condenser 7 which are sequentially connected through a working fluid pipeline 10.

[0031] The jacket water pipeline 9 of the vehicle's engine 8 flows through the preheater 4 and heats it, and the exhaust pipeline 11 of the engine 8 is connected to the flue gas inlet and the flue gas outlet of the flue gas evaporator 5 and heats it.

[0032] A bypass pipe 12 is connected in parallel at both ends of the expander 6, a bypass valve 13 is provided on the bypass pipe 12, a first valve 14 and a second valve 15 are provided at the inlet and outlet of the expansion valve respectively, and a third valve 16 and a fourth valve 17 are provided at the inlet and outlet of the working fluid pump 2 respectively.

[0033] In the vehicle-mounted waste heat recovery system of the present invention, the system utilizes the preheater 4 to recover the waste heat when the engine 8 is working, and utilizes the flue gas evaporator 5 to recover the heat of the flue gas generated by the engine 8, thereby utilizing the above-mentioned recovered waste heat to perform work on the expander 6, thereby realizing the power supply to the expander 6, and further effectively realizing the utilization of waste heat.

[0034] It needs to be explained that the principle of waste heat recovery by the preheater 4 is as follows: the cylinder jacket water pipe 9 is arranged around the cylinder body of the engine 8. At this time, the water in the cylinder jacket water pipe 9 absorbs the waste heat generated by the operation of the engine 8. After flowing out to the outside of the engine 8, the cylinder jacket water pipe 9 continues to flow through the preheater 4. A first heat exchange pipe for circulating the working medium is arranged in the preheater 4. The working medium in the first heat exchange pipe exchanges heat with the hot water in the cylinder jacket water pipe 9, that is, the water in the cylinder jacket water pipe 9 absorbs the waste heat from the operation of the engine 8, and further uses the absorbed waste heat from the operation of the engine 8 to heat the working medium in the first heat exchange pipe, thereby realizing the recovery of the waste heat from the operation of the engine 8.

[0035] The principle of waste heat recovery by the flue gas evaporator 5 is as follows: the exhaust pipe 11 of the engine 8 in the exhaust gas turbocharger system is connected to the flue gas inlet and the flue gas outlet of the flue gas evaporator 5, and a second heat exchange pipe for circulating the working medium is provided in the flue gas evaporator 5. At this time, the flue gas entering the flue gas evaporator 5 heats the second heat exchange pipe, so that the working medium in the second heat exchange pipe absorbs the waste heat of the flue gas of the engine 8, thereby realizing the recovery of the waste heat of the flue gas of the engine 8.

[0036] The specific working principle of the vehicle-mounted waste heat recovery system according to the embodiment of the present invention is as follows.

[0037] When the vehicle is just started or idling, the on-board waste heat recovery system opens the bypass valve 13, the third valve 16 and the fourth valve 17. At this time, the working fluid in the system flows out of the liquid storage device 1 and flows through the fourth valve 17, the working fluid pump 2 and the third valve 16 in sequence. After flowing out of the third valve 16, the working fluid first flows through the regenerator 3, and then continues to flow through the preheater 4 to recover the waste heat generated by the engine 8, and further flows through the flue gas evaporator 5 to recover the waste heat of the flue gas of the engine 8. At this time, since the vehicle has just started or is idling, the waste heat generated by the vehicle engine 8 is not enough to meet the start-up conditions of the expander 6. Therefore, the heated working fluid flows through the regenerator 3 again through the bypass pipe 12, and then the working fluid dissipates heat through the condenser 7 and finally returns to the liquid storage device 1, completing a cycle.

[0038] When the vehicle is in operation, the waste heat generated by the vehicle engine 8 meets the opening condition of the expander 6, that is, when the parameters such as the pressure and temperature at the inlet of the expander 6 meet the set conditions for opening the expander 6, the first valve 14 and the second valve 15 in the system are opened, and the low-temperature and low-pressure working fluid in the liquid storage device 1 enters the regenerator 3 under the boosting action of the working fluid pump 2 to perform the first heat exchange with the high-temperature exhaust steam working fluid after work in the high-speed turbine expander 6, and then enters the preheater 4 to absorb the heat of the engine 8 cylinder jacket water to complete the second heat exchange, and finally enters the flue gas evaporator 5 to perform the third heat exchange with the turbocharged exhaust gas to become a high-temperature and high-pressure steam body. The working fluid enters the expander 6 and flows and expands to drive the impeller to rotate and output useful work. The high-temperature exhaust steam after work enters the hot side of the regenerator 3 to release heat, and finally enters the condenser 7 to be absorbed by cold water to become a low-temperature and low-pressure liquid and return to the storage device, thus completing a cycle.

[0039] In the related technologies, the waste heat recovery system is currently more about the research on laboratory-level system structure design and operation methods. Through experimental tests and performance analysis simulating the engine heat source and cold source, the waste heat recovery system is further optimized to maximize its effective output power. The system operation mode and working method are determined according to the steady-state experimental point, and steady-state data analysis is performed on the experimental results of system performance under different engine operating points. The on-board waste heat recovery system is actually in a complex and changing state, and its vehicle operating state changes all the time according to the actual road conditions. Since the waste heat recovery system recovers heat sources by connecting to the engine cylinder liner water circuit and the exhaust circuit, its system state is affected by the vehicle's operating conditions.

[0040] Therefore, in order to solve the technical problems existing in the above-mentioned related technologies, the present invention provides a vehicle-mounted waste heat recovery system, which has at least the following advantages compared with the related technologies.

[0041] (1) High-efficiency waste heat recovery: The preheater 4 and the flue gas evaporator 5 realize dual-channel waste heat recovery of the engine 8 cylinder jacket water and exhaust gas, thereby improving the efficiency of waste heat recovery.

[0042] (2) Flexible control strategy: By using the bypass valve 13 and multiple control valves (such as the first valve 14, the second valve 15, the third valve 16 and the fourth valve 17), the operating mode of the system can be adjusted according to the operating status of the engine 8.

[0043] (3) Strong adaptability: The system can operate under different vehicle operating conditions and can effectively utilize waste heat whether it is idling or in normal driving.

[0044] (4) Energy saving and emission reduction: By recovering the waste heat generated by the engine 8 and converting it into useful work, fuel consumption is reduced and carbon emissions are lowered.

[0045] (5) Improving fuel economy: The recovered waste heat is used for power generation, which can improve the overall thermal efficiency of the engine 8 and thus improve fuel economy.

[0046] (6) The system is stable and reliable: sophisticated control strategies are used to ensure stable operation of the system under different working conditions, avoiding equipment damage caused by excessive temperature or pressure.

[0047] According to some embodiments of the present invention, the third valve 16 and the fourth valve 17 located before and after the working fluid pump 2 can select whether to open the flow channel of the working fluid inside the waste heat recovery system according to the current state of the vehicle. When the vehicle starts or stops, the internal circulation channel of the waste heat recovery system is opened or closed by opening or closing the above two valves.

[0048] like Figure 1 As shown, according to some embodiments of the present invention, the system can control the opening and closing of the first valve 14, the second valve 15 and the bypass valve 13 and the flow rate, so that the high-speed turbine expander 6 is in a safe and efficient operating state based on the vehicle operating conditions.

[0049] For example, when the vehicle is started and stopped, the first valve 14 and the second valve 15 remain closed, and the bypass valve 13 is opened appropriately. At this time, the branch where the expander 6 is located is bypassed, the working fluid does not pass through the expander 6, and the expander 6 is in a non-operating state. When the vehicle is driving and the system state meets the operating conditions of the expander 6 (the expansion machine 6 is turned on to meet the temperature and pressure parameter settings of its inlet and outlet), the branch of the expander 6 is connected to the vehicle-mounted waste heat recovery system by opening the first valve 14 and the second valve 15 and coordinating and gradually closing the bypass valve 13, and its high-temperature and high-pressure working fluid enters the expander 6 to drive the internal impeller to rotate to generate electricity and do work.

[0050] According to some embodiments of the present invention, the system can adjust and control the opening size of the bypass valve 13 to stabilize the overall pressure within the designed operating range, thereby adapting to different vehicle operating conditions.

[0051] For example, when the vehicle is started or running at a lower operating condition, the pressure in the on-board waste heat recovery system is lower than the pressure value under the system design operating condition, and the bypass valve 13 can be closed to establish the system pressure and make it reach the target design pressure value range. When the vehicle stops running or runs at a higher operating condition, the pressure of the on-board waste heat recovery system is higher than the pressure value under the system design operating condition, and the valve opening can be opened to release the pressure and make it reach the target design pressure value range.

[0052] According to some embodiments of the present invention, the system adjusts the flow rate of the working fluid pump 2 to stabilize the internal temperature thereof within the designed operating range, thereby adapting to different vehicle operating conditions.

[0053] For example, when the vehicle is running at a lower operating condition, the temperature of the onboard waste heat recovery system is lower than the temperature value under the system design operating condition. At this time, the speed of the working fluid pump 2 can be reduced to reduce the flow rate of the working fluid circulating in the system, thereby increasing the system temperature and bringing it within the target design temperature value range. When the vehicle is running at a higher operating condition, the temperature of the onboard waste heat recovery system is higher than the temperature value under the system design operating condition. At this time, the speed of the working fluid pump 2 can be increased to increase the flow rate of the working fluid circulating in the system, thereby reducing the system temperature and bringing it within the target design temperature value range.

[0054] like Figure 1 As shown, according to some embodiments of the present invention, the vehicle-mounted waste heat recovery system specifically includes the following working conditions.

[0055] In case 1, when the vehicle is stopped or idling, all valves inside the on-board waste heat recovery system remain closed and the on-board waste heat recovery system does not operate.

[0056] In case 2, when the vehicle starts, the third valve 16 and the fourth valve 17 are opened, and the bypass valve 13 is adjusted to a certain opening (the recommended opening is 40%, and the specific value depends on the system properties and actual conditions). As the exhaust flow and temperature gradually increase, the working fluid pump 2 is turned on, and the speed of the working fluid pump 2 is continuously increased as the system temperature rises, so that the temperature in the system is maintained within the target design temperature value range (this target design temperature is determined according to the system design and the working fluid properties). As the system pressure continues to increase, the system pressure is maintained within the target design pressure value range (this target design pressure is determined according to the system design and the working fluid properties) by adjusting and increasing the opening of the bypass valve 13.

[0057] Case three, when the vehicle is running, it is monitored that the temperature and pressure at the inlet of the expander 6 meet its opening conditions, so the branch where the expander 6 is located is intervened. The specific operation process is to open the second valve 15 first, and then gradually open the first valve 14, and at the same time coordinate with the reduction of the opening of the bypass valve 13 until it is completely closed. In this process, the expander 6 starts to rotate and gradually outputs effective work. During operation, if the inlet temperature and pressure of the expander 6 are too high or too low to meet its working conditions, it is judged that the expander 6 cannot work, and the bypass pipeline 12 needs to be intervened. The specific operation process is to gradually open the bypass valve 13 and coordinate with the reduction of the opening of the first valve 14 until the first valve 14 is completely closed, and then close the second valve 15 at the outlet of the expander 6, thereby closing the branch where the expander 6 is located.

[0058] In case 4, when the vehicle is running above the design operating condition of the on-board waste heat recovery system, the internal pressure and temperature of the on-board waste heat recovery system are higher than the target design value range, and the bypass valve 13 and the speed of the working fluid pump 2 are adjusted to maintain them within the target value range. The system can reduce the system pressure by increasing the opening of the bypass valve 13 and reduce the system temperature by increasing the speed of the working fluid pump 2.

[0059] Case 5: When the vehicle is running under the design working condition of the on-board waste heat recovery system, the internal pressure and temperature of the on-board waste heat recovery system are lower than the target design value range, and the bypass valve 13 and the speed of the working fluid pump 2 are adjusted to maintain them within the target value range. The system can increase the system pressure by reducing the opening of the bypass valve 13 and increase the system temperature by reducing the speed of the working fluid pump 2.

[0060] In case 6, when the vehicle state changes to shutdown or idling, the onboard waste heat recovery system is shut down after the exhaust flow and temperature decrease. The speed of the working fluid pump 2 is adjusted to zero to stop it, and then all valves in the onboard waste heat recovery system are closed, so that the liquid working fluid after the outlet of the working fluid pump 2 is fully back-pressed, and most of the liquid working fluid is stored in the liquid storage device 1 and the condenser 7.

[0061] The control method, control device and vehicle-mounted waste heat recovery system of the vehicle-mounted waste heat recovery system proposed by the present invention are described below with reference to the accompanying drawings. Among them, before the embodiment of the present invention is described in detail, the entire application scenario is first described. The control method, control device, electronic device and computer-readable storage medium of the vehicle-mounted waste heat recovery system of the embodiment of the present invention can be applied to the local vehicle-mounted waste heat recovery system, and can also be applied to the cloud platform in the Internet field, or other types of cloud platforms in the Internet field, or can also be applied to third-party devices. Among them, third-party devices may include many different types such as mobile phones, tablet computers, notebooks, vehicle-mounted computers and other smart terminals.

[0062] The following is an explanation of the control method applicable to a vehicle-mounted waste heat recovery system as an example. It should be understood that the control method of the embodiment of the present invention can also be applied to a cloud platform and third-party equipment.

[0063] like Figure 1 and Figure 2 As shown, the control method of the vehicle waste heat recovery system according to the second aspect of the present invention includes: Step S1, obtaining the current vehicle working stage of the vehicle.

[0064] In this step, the control system needs to collect data from vehicle sensors, including but not limited to vehicle speed, engine 8 speed, engine 8 load, engine 8 temperature, exhaust temperature and flow, etc. Through these data, the control system can determine the current working stage of the vehicle.

[0065] The specific working process includes: (1) Data collection: The sensor continuously monitors the various operating parameters of the vehicle and transmits the data to the on-board controller. (2) State recognition: The on-board controller recognizes the working stage of the vehicle based on the received data, for example: Startup stage: The engine 8 has just started, and the speed and temperature are low. Idle stage: The engine 8 is in an idle state, and the speed and load are low. Driving stage: The vehicle is driving, and the speed and load of the engine 8 change according to the driving conditions. Parking stage: The vehicle is stopped, and the engine 8 may be turned off or in an idle state.

[0066] Step S2: Control and adjust the working state and working parameters of the on-board waste heat recovery system according to the vehicle working stage

[0067] In step S2, after identifying the working stage of the vehicle, the control system adjusts the working state and parameters of the on-board waste heat recovery system according to pre-set rules to ensure that the system operates under optimal conditions.

[0068] The specific working process is as follows: the control system executes the corresponding control logic according to the identified vehicle working stage. The flow direction and flow rate of the working fluid are controlled by adjusting the opening of the first valve 14, the second valve 15, the third valve 16, the fourth valve 17 and the bypass valve 13 to adapt to the current vehicle state. For example, the speed of the working fluid pump 2 is adjusted as needed to change the flow rate of the working fluid in the system, thereby affecting the system temperature and pressure. For another example, whether to enable the expander 6 to generate power is determined according to the operating conditions of the expander 6, and the intervention or exit of the expander 6 is achieved through the coordinated control of the first valve 14, the second valve 15 and the bypass valve 13.

[0069] In some specific embodiments of the present invention, the steps of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically include: When the vehicle is currently in the shutdown stage or the idling stage, the first valve 14, the second valve 15, the third valve 16, the fourth valve 17 and the bypass valve 13 in the on-board waste heat recovery system are controlled to be closed, so that the on-board waste heat recovery system is shut down.

[0070] It can be understood that the above embodiment is for the case where the vehicle engine 8 is not running and the vehicle waste heat recovery system is in a closed state. All valves in the entire vehicle waste heat recovery system are closed, no working fluid flows inside the system, and the system does not exchange heat with the engine 8.

[0071] In some other specific embodiments of the present invention, the step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically includes: When the vehicle is currently in the starting stage, the third valve 16, the fourth valve 17 and the bypass valve 13 are controlled to open, so that the on-board waste heat recovery system operates; When it is determined that the on-board waste heat recovery system is running, the inlet working fluid parameters at the inlet of the expander 6 are obtained, and the opening of the bypass valve 13 and / or the speed of the working fluid pump 2 are controlled and adjusted according to the inlet working fluid parameters.

[0072] Furthermore, the inlet working fluid parameters include the inlet working fluid temperature and the inlet working fluid pressure, and the step of controlling and adjusting the opening of the bypass valve 13 and / or the speed of the working fluid pump 2 according to the inlet working fluid parameters specifically includes: According to the comparison result between the inlet working fluid temperature and the set temperature range, the speed of the working fluid pump 2 is controlled and adjusted so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve 13 is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

[0073] For example, if the inlet working fluid temperature exceeds the set temperature range, the speed of the working fluid pump 2 is increased to reduce the inlet working fluid temperature to within the set temperature range; if the inlet working fluid temperature is lower than the set temperature range, the speed of the working fluid pump 2 is reduced to increase the inlet working fluid temperature to within the set temperature range.

[0074] For another example, if the inlet working fluid pressure exceeds the set pressure range, the opening of the bypass valve 13 is increased to reduce the inlet working fluid pressure to within the set pressure range; if the inlet working fluid pressure is lower than the set pressure range, the opening of the bypass valve 13 is reduced to increase the inlet working fluid pressure to within the set pressure range.

[0075] It can be understood that the above embodiment is for the startup process of waste heat recovery. By opening the third valve 16 and the fourth valve 17 and controlling the opening of the bypass valve 13, the entire on-board waste heat recovery system forms a closed loop, in which the working fluid circulates to exchange heat with the engine 8. As the operating conditions of the engine 8 continue to improve, the temperature and pressure of the on-board waste heat recovery system increase. At this time, on the one hand, the speed of the working fluid pump 2 can be controlled to adjust the flow rate of the working fluid inside the system, thereby maintaining the system temperature within the target temperature range of the design conditions. On the other hand, the opening of the bypass valve 13 can be controlled to maintain the system pressure within the target pressure range of the design conditions.

[0076] In some further specific embodiments of the present invention, the step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically further includes: When the vehicle completes the starting phase and enters the running phase, obtaining the inlet working medium parameters at the inlet of the expander 6; If it is determined that the inlet working medium parameter meets the set parameter condition, the first valve 14 and the second valve 15 are controlled to be opened to enable the expander 6 to operate, and the bypass valve 13 is controlled to be closed or reduced to a first set opening.

[0077] Further, the steps of controlling the first valve 14 and the second valve 15 to open so that the expander 6 operates, and controlling the bypass valve 13 to close specifically include: Control the second valve 15 to open to the maximum opening; While the first valve 14 is opened and controlled to gradually increase its opening, the bypass valve 13 is controlled to gradually decrease its opening until the first valve 14 reaches the second set opening and the bypass valve 13 is closed or reaches the first set opening.

[0078] In this embodiment, the above situation is for the process of the expansion machine 6 branch intervening in the vehicle-mounted waste heat recovery system to generate power. When the system monitors that the inlet temperature and pressure of the expansion machine 6 reach the target value of the system design turbine opening condition, the second valve 15 located at the outlet of the expansion machine 6 is first opened, and then the first valve 14 located at the inlet of the expansion machine 6 is gradually opened and coordinated with the bypass valve 13 to reduce the opening degree until the branch where the expansion machine 6 is located is fully involved, and the expansion machine 6 starts to generate power. During the operation of the expansion machine 6, its parameters must be monitored at all times. If its temperature, pressure and other parameters are not within the design range, the expansion machine 6 must be bypassed in time to stop its operation.

[0079] Furthermore, the inlet working fluid parameters include an inlet working fluid temperature and an inlet working fluid pressure, and the parameter setting condition is that the inlet working fluid temperature is within a set temperature range and the inlet working fluid pressure is within a set pressure range; the control method further includes: During the operation of the expander 6, the inlet working fluid temperature and the inlet working fluid pressure of the expander 6 are monitored; According to the comparison result between the inlet working fluid temperature and the set temperature range, the speed of the working fluid pump 2 is controlled and adjusted so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve 13 is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

[0080] For example, according to the comparison result between the inlet working fluid temperature and the set temperature range, the step of controlling and adjusting the speed of the working fluid pump 2 specifically includes: When the inlet working fluid temperature exceeds the set temperature range, the speed of the working fluid pump 2 is controlled to increase; when the inlet working fluid temperature is lower than the set temperature range, the speed of the working fluid pump 2 is controlled to decrease.

[0081] For another example, the step of controlling and adjusting the opening of the bypass valve 13 according to the comparison result between the inlet working fluid pressure and the set pressure range specifically includes: When the inlet working medium pressure exceeds the set pressure range, the opening of the bypass valve 13 is controlled to increase; when the inlet working medium pressure is lower than the set pressure range, the opening of the bypass valve 13 is controlled to decrease.

[0082] It can be understood that the above embodiment is a method for adjusting the vehicle-mounted waste heat recovery system according to the vehicle operating state. During the operation of the vehicle, due to the instability of the waste heat source of the engine 8, the vehicle-mounted waste heat recovery system that exchanges heat with the engine 8 will be affected, causing the system temperature and pressure to fluctuate. In the specific control process, the change in system temperature can be achieved by adjusting the speed of the working fluid pump 2 to change the working fluid flow rate circulating in the system, and the system pressure can be achieved by changing the opening of the bypass valve 13 to achieve the effect of pressure relief or pressure increase.

[0083] In addition, since the waste heat recovery system has thermal inertia and hysteresis, the temperature and pressure need to be adjusted separately and in a step-by-step manner during the process of adjusting the temperature and pressure, so as to ensure that the waste heat recovery system operates stably and safely during vehicle operation.

[0084] A specific embodiment of the control method of the present invention is given below with reference to the accompanying drawings, and its working method can be decomposed as follows.

[0085] (1) The vehicle is shut down or idling

[0086] The on-board waste heat recovery system has no heat source for heat exchange, no working fluid flows in the system, all valves are closed, and the entire on-board waste heat recovery system does not operate.

[0087] (2) Vehicle starting

[0088] like Figure 1As shown, the on-board waste heat recovery system starts as the vehicle starts to move, and the third valve 16, the fourth valve 17 and the bypass valve 13 are opened to a certain opening (the appropriate valve opening can be set according to the system conditions). The working fluid pump 2 is turned on and the working fluid begins to circulate inside the on-board waste heat recovery system loop. The speed of the working fluid pump 2 increases as the vehicle operating conditions gradually improve, so that enough working fluid flows inside the system to absorb heat and maintain the system temperature within the design target value range of the on-board waste heat recovery system. At the same time, attention should be paid to the pressure of the on-board waste heat recovery system, and the opening of the bypass valve 13 should be adjusted to maintain the system pressure within the design target value range of the system. Since the on-board waste heat recovery system has thermal inertia and hysteresis, the temperature and pressure regulation need to be adjusted separately and stepped to ensure stable and safe operation of the system.

[0089] (3) The vehicle operation status meets the working conditions of the expander 6 of the on-board waste heat recovery system

[0090] like Figure 1 As shown, as the vehicle is running, the temperature and pressure of the on-board waste heat recovery system gradually and steadily increase. When the temperature and pressure at the outlet of the flue gas evaporator 5 (that is, the inlet of the expander 6) are monitored to reach the opening conditions of the expander 6, the expander 6 can be involved in the system to generate electricity and do work. After opening the second valve 15, the first valve 14 is opened by step adjustment. At the same time, the opening of the bypass valve 13 is coordinated to decrease, so that the branch of the expander 6 is gradually opened until it is fully involved. During this period, the power generation of the expander 6 gradually increases until the target power generation is reached. During operation, the parameters of the expander 6 need to be monitored at all times. When it is found that the parameters such as the turbine inlet temperature, pressure, and motor speed are not within the system design target range or abnormal values ​​appear, the expander 6 needs to stop running immediately. At this time, the opening of the first valve 14 is closed alternately and the opening of the bypass valve 13 is opened, so that the branch of the expander 6 is gradually closed until it is completely cut off, and finally the second valve 15 is closed.

[0091] (4) The vehicle is operating above the design operating conditions of the on-board waste heat recovery system

[0092] like Figure 1 As shown, during the operation of the vehicle, the working condition of the engine 8 will change at any time according to the actual road conditions and driving requirements. When it operates above the design working condition of the on-board waste heat recovery system, the heat source of the system is higher than the design value, causing the system temperature and pressure to exceed the design target value. First, increase the opening of the bypass valve 13 to release the pressure. Secondly, increase the speed of the working fluid pump 2 to increase the circulating flow of the working fluid in the system, thereby reducing the system temperature. The adjustment of temperature and pressure needs to be carried out separately and step by step so that the on-board waste heat recovery system operates within the design target range.

[0093] (5) The vehicle operating conditions are below the design conditions of the on-board waste heat recovery system.

[0094] like Figure 1 As shown, when the engine 8 is operating under the system design conditions, the heat source of the system is too low, resulting in the system temperature and pressure being lower than the design target values. First, the opening of the bypass valve 13 is reduced to increase the pressure. Secondly, the speed of the working fluid pump 2 can be reduced to reduce the circulating flow of the working fluid in the system, thereby increasing the system temperature. The temperature and pressure need to be adjusted separately and step by step so that the on-board waste heat recovery system operates within the design target range. The vehicle stops running or enters standby mode

[0095] (6) The vehicle is stopped or enters idle mode

[0096] When the vehicle is in shutdown or idling state, the exhaust flow and temperature will drop rapidly, and the onboard waste heat recovery system needs to stop running. The speed of working fluid pump 2 is adjusted to zero, and all valves are closed.

[0097] In summary, the working method of the vehicle-mounted waste heat recovery system proposed in the present invention is applicable to a single-machine waste heat recovery system equipped with an organic Rankine cycle. This is a closed circulation system, in which the organic working fluid is converted into high-temperature and high-pressure steam at room temperature and pressure in the liquid storage device 1 through the working fluid pump 2 and various heat exchangers, and then enters the expander 6 to drive the impeller to rotate and do work. The valves installed inside the system are used to start, stop, adjust, and safely operate the entire vehicle-mounted waste heat recovery system.

[0098] The control device of the vehicle-mounted waste heat recovery system provided by the present invention is described below. The control device of the vehicle-mounted waste heat recovery system described below and the control method of the vehicle-mounted waste heat recovery system described above can be referred to each other.

[0099] like Figure 3 As shown, a control device for a vehicle-mounted waste heat recovery system according to an embodiment of the third aspect of the present invention includes: An acquisition module 110 is used to acquire the current vehicle working stage of the vehicle; The control module 120 is used to control and adjust the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage.

[0100] Figure 4 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 4As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830 and a communication bus 840, wherein the processor 810, the communication interface 820 and the memory 830 communicate with each other through the communication bus 840. The processor 810 may call the logic instructions in the memory 830 to execute the control method of the vehicle-mounted waste heat recovery system, including: obtaining the current vehicle working stage of the vehicle; and controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage.

[0101] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0102] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the control methods of the vehicle-mounted waste heat recovery system provided by the above methods, including: obtaining the current vehicle working stage of the vehicle; according to the vehicle working stage, controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system.

[0103] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the control method of the vehicle-mounted waste heat recovery system provided by the above-mentioned methods, including: obtaining the current vehicle working stage of the vehicle; according to the vehicle working stage, controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system.

[0104] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0105] Through the description of the above implementation modes, those skilled in the art can clearly understand that each implementation mode can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on such an understanding, the above technical solution can essentially or in other words be embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vehicle-mounted waste heat recovery system, It is characterized in that It includes a liquid storage device, a working fluid pump, a regenerator, a preheater, a flue gas evaporator, an expander and a condenser which are sequentially connected through a working fluid pipeline; The cylinder water pipeline of the vehicle engine flows through the preheater and heats it, and the exhaust pipeline of the engine is connected to the smoke inlet and the smoke outlet of the smoke evaporator and heats them; A bypass pipe is connected in parallel at both ends of the expander, a bypass valve is arranged on the bypass pipe, a first valve and a second valve are arranged at the inlet and outlet of the expansion valve respectively, and a third valve and a fourth valve are arranged at the inlet and outlet of the working fluid pump respectively.

2. A control method for the vehicle-mounted waste heat recovery system according to claim 1, It is characterized in that include: Get the current working stage of the vehicle; According to the vehicle working stage, the working state and working parameters of the vehicle-mounted waste heat recovery system are controlled and adjusted.

3. The control method of the vehicle waste heat recovery system according to claim 2, It is characterized in that The step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically includes: When the vehicle is currently in a shutdown stage or an idling stage, the first valve, the second valve, the third valve, the fourth valve and the bypass valve in the on-board waste heat recovery system are controlled to be closed so that the on-board waste heat recovery system is shut down.

4. The control method of the vehicle waste heat recovery system according to claim 2, It is characterized in that The step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically includes: When the vehicle is currently in a starting stage, controlling the third valve, the fourth valve and the bypass valve to open, so that the on-board waste heat recovery system operates; When it is determined that the on-board waste heat recovery system is running, an inlet working fluid parameter at the inlet of the expander is obtained, and the opening of the bypass valve and / or the speed of the working fluid pump are controlled and adjusted according to the inlet working fluid parameter.

5. The control method of the vehicle waste heat recovery system according to claim 4, It is characterized in that The inlet working fluid parameters include inlet working fluid temperature and inlet working fluid pressure, and the step of controlling and adjusting the opening of the bypass valve and / or the speed of the working fluid pump according to the inlet working fluid parameters specifically includes: According to the comparison result between the inlet working fluid temperature and the set temperature range, controlling and adjusting the speed of the working fluid pump so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

6. The control method of the vehicle waste heat recovery system according to claim 4, It is characterized in that The step of controlling and adjusting the working state and working parameters of the vehicle-mounted waste heat recovery system according to the vehicle working stage specifically includes: When the vehicle completes the starting phase and enters the running phase, obtaining an inlet working fluid parameter at the inlet of the expander; If it is determined that the inlet working fluid parameter meets the set parameter condition, the first valve and the second valve are controlled to be opened to enable the expander to operate, and the bypass valve is controlled to be closed or reduced to a first set opening.

7. The control method of the vehicle waste heat recovery system according to claim 6, It is characterized in that The step of controlling the first valve and the second valve to open so that the expander operates, and controlling the bypass valve to close specifically includes: Controlling the second valve to open to a maximum opening; While opening and controlling the opening of the first valve to gradually increase, the opening of the bypass valve is controlled to gradually decrease until the first valve reaches the second set opening and the bypass valve is closed or reaches the first set opening.

8. The control method of the vehicle waste heat recovery system according to claim 6, It is characterized in that The inlet working fluid parameters include inlet working fluid temperature and inlet working fluid pressure, and the set parameter condition is that the inlet working fluid temperature is within the set temperature range and the inlet working fluid pressure is within the set pressure range; Then the control method further includes: During the operation of the expander, monitoring the inlet working fluid temperature and the inlet working fluid pressure of the expander; According to the comparison result between the inlet working fluid temperature and the set temperature range, controlling and adjusting the speed of the working fluid pump so that the inlet working fluid temperature is adjusted to within the set temperature range; According to the comparison result between the inlet working medium pressure and the set pressure range, the opening of the bypass valve is controlled and adjusted so that the inlet working medium pressure is adjusted to within the set pressure range.

9. The control method of the vehicle-mounted waste heat recovery system according to claim 5 or 8, It is characterized in that The step of controlling and adjusting the speed of the working fluid pump according to the comparison result of the inlet working fluid temperature and the set temperature range specifically includes: When the inlet working fluid temperature exceeds the set temperature range, controlling the speed of the working fluid pump to increase; When the inlet working fluid temperature is lower than the set temperature range, controlling the speed of the working fluid pump to decrease; And the step of controlling and adjusting the opening of the bypass valve according to the comparison result of the inlet working fluid pressure and the set pressure range specifically includes: When the inlet working fluid pressure exceeds the set pressure range, controlling the opening of the bypass valve to increase; When the inlet working fluid pressure is lower than the set pressure range, the opening of the bypass valve is controlled to decrease.

10. A control device based on the vehicle waste heat recovery system according to claim 1, It is characterized in that include: An acquisition module, used to acquire the current vehicle working stage of the vehicle; The control module is used to control and adjust the working state and working parameters of the on-board waste heat recovery system according to the working stage of the vehicle.

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