Hybrid system, control method, and vehicle

Abstract

The application belongs to the technical field of hybrid power equipment, and particularly relates to a hybrid power system, a control method and a vehicle, wherein the hybrid power system comprises an engine, an exhaust turbine assembly, an electric compressor assembly and a control assembly; the exhaust turbine assembly comprises a turbine, a generator and a battery connected in sequence, the air inlet end of the turbine is connected with the air outlet end of the engine; the battery is connected with the engine; the electric compressor assembly comprises an electric motor and a compressor connected in sequence, the air outlet of the compressor is connected with the air inlet pipe of the engine; the control assembly comprises an ECU and a pressure sensor connected in sequence, the pressure sensor is arranged at the air inlet end of the engine, and the ECU is further connected with the battery and the electric motor respectively. Through the above device, the precise control of the air flow can be realized, the system response is accelerated, the air inlet pipeline is simplified, the throttling loss and the exhaust energy loss are reduced, and the engine efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of hybrid power equipment technology, and specifically relates to a hybrid power system, control method and vehicle. Background Technology

[0002] Traditional turbochargers rely on engine acceleration to drive the turbine, with the turbine and compressor coaxially connected. The turbine's rotation drives the compressor, increasing the density of the intake air and achieving boost. However, this structure suffers from "turbo lag," where the boost pressure increases lags behind changes in engine operating conditions. To address this issue, a new turbocharger has been developed. This improved turbocharger separates the traditional coaxial turbocharger into two independent subsystems: a turbine and a compressor, each controlled separately. The turbine is connected to a generator, where exhaust gases from engine combustion drive the turbine to generate electricity, which is stored in a battery. The compressor is connected to an electric motor, drawing power from the battery and using an inverter to control the speed-regulating motor.

[0003] However, the above-mentioned improved structure does not take into account the situation where the turbine generator battery is low in power. The compressor is driven by an electric motor, which draws power from the battery. The battery, in turn, generates electricity from an alternator driven by the turbocharger. Therefore, the power output at the turbine end needs to be higher than the power consumption at the compressor end to ensure that the battery always has power; otherwise, the electric motor cannot start. Summary of the Invention

[0004] The purpose of this invention is to provide a hybrid power system, control method, and vehicle to at least solve some of the aforementioned technical problems.

[0005] The first aspect of the present invention provides a hybrid power system, comprising:

[0006] engine;

[0007] An exhaust gas turbine assembly includes a turbine, a generator, and a battery connected in sequence, wherein the intake end of the turbine is connected to the exhaust end of the engine; and the battery is connected to the engine.

[0008] An electric compressor assembly includes an electric motor and a compressor connected together, wherein the outlet of the compressor is connected to the intake pipe of the engine;

[0009] The control assembly includes a connected ECU and a pressure sensor, the pressure sensor being located at the engine intake end, and the ECU being connected to the battery and the electric motor, respectively.

[0010] The hybrid power system provided by this invention also includes at least the following additional technical features:

[0011] In some specific embodiments of the present invention, the engine includes a plurality of cylinders connected in parallel, the plurality of cylinders being connected to the compressor via an intake manifold and to the turbine via an exhaust manifold.

[0012] In some specific embodiments of the present invention, an intake pipe and an outlet pipe are also included, wherein the intake pipe is connected between the compressor and the intake manifold, and the outlet pipe is connected between the outlet manifold and the turbine.

[0013] In some specific embodiments of the present invention, the intake pipe is further provided with an intercooler.

[0014] In some specific embodiments of the present invention, the battery is further provided with an external charging path.

[0015] In some specific embodiments of the present invention, the turbine is an adjustable nozzle type, a bypass valve type, or a variable cross-section volute type.

[0016] In some specific embodiments of the present invention, the generator is an AC generator with an internal rectifier.

[0017] A second aspect of the present invention also provides a control method for the above-described hybrid power system, implemented using any one of the above-described hybrid power systems, comprising the following steps:

[0018] The required intake pressure value is determined based on the accelerator pedal opening or brake pedal opening, engine speed, and intake air temperature.

[0019] The actual intake pressure at the engine intake end is obtained based on a pressure sensor; PID closed-loop calculation is performed based on the actual intake pressure and the required intake pressure to obtain the desired compressor speed; and a drive motor is used to rotate the compressor according to the desired speed.

[0020] In some specific embodiments of the present invention, determining the required intake pressure value based on the accelerator pedal opening or brake pedal opening, engine speed, and intake air temperature includes:

[0021] Determine the engine's required torque based on the accelerator pedal opening and engine speed;

[0022] The required intake air volume of the engine is obtained based on the required torque, and the required intake air pressure value is obtained based on the required intake air volume and intake air temperature.

[0023] A third aspect of the present invention also provides a vehicle comprising the hybrid power system described in any one of the preceding claims.

[0024] In the hybrid power system provided by this invention, the exhaust gas energy from the engine can be converted into electrical energy and stored in the battery via a turbine and generator. Part of the engine's mechanical energy can also be converted into electrical energy and stored in the battery. Combined with external charging equipment, multiple charging and power supply paths can be complementary, completely avoiding situations where the battery is low. When powered by the battery, the electric motor drives the compressor. Combined with pressure sensor feedback, precise control of the engine boost pressure can be achieved. In this structure, the compressor and turbine are no longer rigidly connected and can be arranged independently, increasing the flexibility of the intake and exhaust pipe layout. It also eliminates the need for an exhaust bypass valve to balance the turbocharger speed and boost pressure to achieve asynchronous speeds, reducing energy loss through the bypass valve. All operating conditions of the engine can be precisely controlled by the compressor to control the intake airflow, thus eliminating the need for a throttle valve, reducing throttling losses, shortening the intake pipe, and lowering intake resistance. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the hybrid power system provided by the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Electric motor, 2-Compressor, 3-Intercooler, 4-Intake pipe, 5-Intake manifold, 6-Engine, 7-Exhaust pipe, 8-Turbine, 9-Generator, 10-Battery, 11-MCU, 12-ECU, 13-Pressure sensor. Detailed Implementation

[0029] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0030] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0031] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0032] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0033] like Figure 1 As shown, the first aspect of the present invention provides a hybrid power system, comprising:

[0034] Engine 6;

[0035] The exhaust gas turbine assembly includes a turbine 8, a generator 9, and a battery 10 connected in sequence. The intake end of the turbine 8 is connected to the exhaust end of the engine 6; the battery 10 is connected to the engine 6.

[0036] The electric air compressor assembly includes a motor 1 and an air compressor 2 connected together, wherein the air outlet of the air compressor 2 is connected to the air intake pipe 4 of the engine 6.

[0037] The control assembly includes an ECU 12 and a pressure sensor 13 connected to each other. The pressure sensor 13 is located at the intake end of the engine 6. The ECU 12 is also connected to the battery 10 and the electric motor 1.

[0038] Preferably, the control component further includes an MCU 11 (Microcontroller Unit, or MCU) electrically connected to the ECU 12 (Electronic Control Unit, or ECU). The MCU 11 is connected between the battery 10 and the motor 1 and is used to start the motor 1 to drive the compressor 2 to rotate based on the instruction of the ECU 12.

[0039] During the control process, ECU 12 calculates the required boost pressure based on the specific operating conditions. This required boost pressure is the required pressure of intake manifold 4. An intake pressure sensor 13 is installed at intake manifold 4, which can feed back the pressure of intake manifold 4 to ECU 12 in real time. ECU 12 performs closed-loop operation based on the required value and the actual value of intake manifold 4 pressure, and sends the required compressor 2 speed signal to the motor controller. The controller controls the motor to drive the compressor 2 to rotate at the desired speed and continuously adjusts the required speed so that the pressure of intake manifold 4 reaches the required boost pressure.

[0040] The exhaust gases from the cylinder on the exhaust side flow through the exhaust pipe 7 to the turbine, driving the turbine to rotate and power the generator 9 to generate electricity, which charges the battery. The battery is charged by three sources: an external power source, the turbine, and the engine 6. The compressor 2 motor is powered by the battery. In most cases, the turbine's power output is higher than that of the compressor 2, so the electricity generated by the turbine is sufficient to meet the compressor 2's needs. Simultaneously, the other two charging sources for the battery ensure a sufficient battery charge, preventing the compressor 2 from failing due to low battery power. When the turbine has sufficient power, it can also supply power to the vehicle's electric mode or other power sources, achieving energy recovery.

[0041] In the above structure, the exhaust gas energy discharged from engine 6 can be converted into electrical energy and stored in battery 10 via turbine 8 and generator 9. Part of the mechanical energy of engine 6 can also be converted into electrical energy and stored in battery 10. Combined with external charging equipment, multiple charging and power supply paths can be complementary, completely avoiding situations where the battery charge is low. When the battery 10 supplies power, electric motor 1 drives compressor 2 to rotate. Combined with the pressure signal feedback from pressure sensor 13, precise control of the boost pressure of engine 6 can be achieved. In this structure, compressor 2 and turbine 8 are no longer rigidly connected and can be arranged independently, thus increasing the flexibility of the intake and exhaust pipe 7 layout. It also eliminates the need for an exhaust bypass valve to balance the turbocharger speed and boost pressure to achieve asynchronous speeds, reducing energy loss through the bypass valve. All operating conditions of engine 6 can be precisely controlled by compressor 2 for intake airflow, thus eliminating the need for a throttle valve, reducing throttling losses, shortening the intake pipe 4, and reducing intake resistance.

[0042] In some specific embodiments of the present invention, the engine 6 includes a plurality of cylinders connected in parallel, the plurality of cylinders being connected to the compressor 2 via an intake manifold 5 and to the turbine 8 via an exhaust manifold.

[0043] In some specific embodiments of the present invention, an intake pipe 4 and an outlet pipe 7 are also included. The intake pipe 4 is connected between the compressor 2 and the intake manifold 5, and the outlet pipe 7 is connected between the outlet manifold and the turbine 8.

[0044] In some specific embodiments of the present invention, the air intake pipe 4 is further provided with an intercooler 3.

[0045] In some specific embodiments of the present invention, the storage battery 10 is further provided with an external charging path.

[0046] In some specific embodiments of the present invention, the turbine 8 is an adjustable nozzle type, a bypass valve type, or a variable cross-section volute type.

[0047] In some specific embodiments of the present invention, the generator 9 is an AC generator 9 with an internal rectifier.

[0048] A second aspect of the present invention also provides a control method for the above-described hybrid power system, implemented using any one of the above-described hybrid power systems, comprising the following steps:

[0049] The required intake pressure value is determined based on the accelerator pedal opening or brake pedal opening, engine speed, and intake air temperature.

[0050] The actual intake pressure value at the intake end of engine 6 is obtained based on pressure sensor 13; PID closed-loop calculation is performed based on the actual intake pressure value and the required intake pressure value to obtain the desired speed of compressor 2; drive motor 1 to drive compressor 2 to rotate according to the desired speed.

[0051] In some specific embodiments of the present invention, determining the required intake pressure value based on the accelerator pedal opening or brake pedal opening, engine speed, and intake air temperature includes:

[0052] The required torque of engine 6 is determined based on the accelerator pedal opening and engine 6 speed.

[0053] The required intake air volume of engine 6 is obtained based on the required torque, and the required intake air pressure value is obtained based on the required intake air volume and intake air temperature.

[0054] Specifically, based on the accelerator pedal opening and engine speed at 6 RPM, the required torque is obtained by consulting the accelerator pedal mapping table or brake pedal mapping table (accelerator pedal map or brake pedal map). The accelerator pedal map or brake pedal map can be pre-calibrated, with the engine speed at 6 RPM on the horizontal axis and the accelerator pedal opening or brake pedal opening on the vertical axis. The intersection of the engine speed at 6 RPM and the accelerator pedal opening or brake pedal opening represents the required torque.

[0055] The required intake air volume is the amount of air needed to achieve the required torque. It can be calculated from the required torque, and then the required intake pressure can be obtained based on the current intake air temperature and the required intake air volume. Specifically, to obtain the required intake pressure from the required torque, firstly, a preset mapping table, denoted as the FMTC map, is consulted. The horizontal axis of the FMTC map represents engine speed (6 RPM), and the vertical axis represents the required torque. The content of the FMTC map is the amount of fuel required for each working cycle of engine speed (6 RPM), i.e., the amount of fuel per cycle. This amount of fuel is multiplied by the equivalence ratio under this operating condition to obtain the required intake air volume. The equivalence ratio is obtained from a preset equivalence ratio mapping table, i.e., the equivalence ratio map. The horizontal axis of the equivalence ratio map is engine speed (6 RPM), and the vertical axis represents the required torque. The content of the equivalence ratio map is the mass ratio of air volume to fuel volume. Finally, the required intake pressure is determined based on the required intake air volume and intake air temperature.

[0056] It should be noted that the FMTC map and the equivalent ratio map can be pre-calibrated. For example, the correspondence between engine speed, required torque, required fuel quantity, and mass ratio of air to fuel can be obtained through experiments, and then the FMTC map and equivalent ratio map can be generated for querying.

[0057] The intake pressure difference is obtained by subtracting the required intake pressure value from the actual intake pressure value. PID control is performed based on the intake pressure difference to obtain the desired speed. ECU 12 commands motor 1 to start based on the desired speed, thereby driving compressor 2 to rotate as desired.

[0058] A third aspect of the present invention also provides a vehicle comprising the hybrid power system described in any one of the preceding claims.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for a hybrid power system, characterized in that, The hybrid power system includes: engine; An exhaust gas turbine assembly includes a turbine, a generator, and a battery connected in sequence, wherein the intake end of the turbine is connected to the exhaust end of the engine; and the battery is connected to the engine. An electric compressor assembly includes an electric motor and a compressor connected together, wherein the outlet of the compressor is connected to the intake pipe of the engine; The control assembly includes an ECU and a pressure sensor connected to each other, the pressure sensor being disposed at the engine intake end, the ECU also being connected to the battery and the electric motor respectively; it also includes an MCU electrically connected to the ECU, the MCU being connected between the battery and the electric motor, and is used to start the electric motor to drive the compressor to rotate based on the ECU's specification; The control methods include: determining the required intake pressure value based on engine speed, intake air temperature, and brake pedal opening; The actual intake pressure at the engine intake end is obtained based on a pressure sensor; PID closed-loop calculation is performed based on the actual intake pressure and the required intake pressure to obtain the desired compressor speed; and a drive motor is used to rotate the compressor according to the desired speed. The required intake pressure value is determined based on brake pedal opening, engine speed, and intake air temperature, including: The required engine torque is determined based on the brake pedal opening and engine speed. The required intake air volume of the engine is obtained based on the required torque, and the required intake air pressure value is obtained based on the required intake air volume and intake air temperature.

2. The control method for a hybrid power system according to claim 1, characterized in that, The engine includes multiple cylinders connected in parallel, and the multiple cylinders are connected to the compressor through an intake manifold and to the turbine through an exhaust manifold.

3. The control method for a hybrid power system according to claim 2, characterized in that, It also includes an intake pipe and an exhaust pipe, wherein the intake pipe is connected between the compressor and the intake manifold, and the exhaust pipe is connected between the exhaust manifold and the turbine.

4. The control method for a hybrid power system according to claim 3, characterized in that, An intercooler is also provided on the air intake pipe.

5. The control method for a hybrid power system according to claim 1, characterized in that, The battery also has an external charging path.

6. The control method for a hybrid power system according to claim 1, characterized in that, The turbine is an adjustable nozzle type, a bypass valve type, or a variable cross-section volute type.

7. The control method for a hybrid power system according to claim 1, characterized in that, The generator is an AC generator with an internal rectifier.

8. A vehicle, characterized in that, The hybrid power system control method described in any one of claims 1-7 is adopted.

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