Transient control system for parallel hybrid power ship and control method thereof

Abstract

The invention discloses a parallel hybrid power ship transient control system which comprises a propeller and a gear box, the gear box is composed of a clutch a, a clutch b and a gear, the clutch a is sequentially connected with an engine and a CAN bus, and the clutch b is sequentially connected with a torque sensor, a shaft tachometer, a reversible motor, an AC / DC device, a storage battery pack and the CAN bus. The system further comprises a cRIO controller with an acquisition card and an upper computer, wherein the cRIO controller is connected with the CAN bus. The invention further discloses a control method. The optimal reversible motor torque and clutch combination pressure are switched in the switching process of different working modes, so that engine speed fluctuation in the switching process of a ship can be reduced, and the working condition of a transmission system can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid power ships, and in particular to a transient control system of a parallel hybrid power ship, and a transient control method thereof in a switching mode. Background Art

[0002] As traditional power equipment using fossil fuels is difficult to meet increasingly stringent emission regulations. Clean energy has become a new choice for ship power because it can effectively achieve energy conservation and emission reduction goals. However, due to the structure and operation mode of the ship, the use of a single energy form to power the ship is limited. Therefore, the ship parallel hybrid system uses the advantages of the engine using clean alternative energy and the characteristics of battery pack energy storage and fast dynamic response, which is a new direction for the green development of ships.

[0003] The ship hybrid power system has different working modes. Its complex power coupling structure improves the redundancy, flexibility, safety, operability and economy of the ship power system. On the other hand, the hybrid power system is composed of different power sources. The mixing of multiple power sources increases the complexity of the system, and each power source has different dynamic response characteristics. Therefore, the ship hybrid power system is not a simple superposition of multiple single energy sources. In order to give full play to the advantages of each power source in the system, it is necessary to formulate a reasonable energy management strategy, allocate the output power or torque of each power source, coordinate electromechanical propulsion, and ensure safe power supply for the entire ship.

[0004] Therefore, how to optimize the switching process of different working modes according to the energy management strategy of the ship, reduce the engine speed fluctuation and improve the working condition of the transmission system, and ensure the safe, smooth and fast switching of the system working mode is the problem solved by the present invention. Summary of the invention

[0005] In view of the above deficiencies in the prior art, one of the objectives of the present invention is to provide a parallel hybrid ship transient control system.

[0006] The technical solution adopted by the present invention to solve its technical problems is: a parallel hybrid ship transient control system, including a propeller and a gearbox, the gearbox is composed of a clutch a, a clutch b and a gear connected to the propeller, the clutch a is connected to the engine and the CAN bus in sequence, the clutch b is connected to the torque sensor, the shaft speed meter, the reversible motor, the AC / DC device, the battery pack and the CAN bus in sequence, and also includes a cRIO controller with an acquisition card connected to the CAN bus and a host computer connected to the cRIO controller, the clutch a and the clutch b are both provided with a pressure sensor, the torque sensor collects the output torque of the reversible motor and transmits it to the acquisition card through the CAN bus, the pressure sensor collects the oil pressure of the clutch a and the clutch b and transmits it to the acquisition card through the CAN bus, the shaft speed meter collects the speed of the reversible motor and transmits it to the acquisition card through the CAN bus, and the acquisition card collects the SOC value of the battery pack through the CAN bus.

[0007] In the parallel hybrid ship transient control system, the torque sensor is installed between the reversible motor and the gear box; the shaft speed meter is installed on the output shaft of the reversible motor.

[0008] The parallel hybrid ship transient control system, whose host computer includes a coordinated optimization decision unit and a transient control unit; the coordinated optimization decision unit is based on the squirrel search optimization algorithm, and analyzes and optimizes the collected engine output torque, reversible motor output torque, and clutch engagement pressure according to the required torque of the actual ship operating conditions under the battery SOC value restriction condition to obtain the reversible motor target torque and clutch target engagement pressure; the transient control unit adjusts the action signal of the power equipment of the coordinated optimization decision unit, that is, the reversible motor target torque and clutch target engagement pressure after the host computer optimizes, based on the squirrel search optimization algorithm to control the reversible motor to complete the torque adjustment and the gearbox to complete the clutch engagement pressure adjustment.

[0009] A second object of the present invention is to provide a control method for a parallel hybrid ship transient control system, comprising the following steps:

[0010] Step 1, obtaining the required torque of the control system, the output torque and speed of the reversible motor, the engagement pressure of clutch a / clutch b, the output torque and speed of the engine, and the SOC value of the battery pack, and transmitting them to the host computer;

[0011] Step 2, judging whether the ship system working mode switching rules are met, if the switching rules are met, the coordination optimization decision unit of the upper computer calculates the reversible motor target torque through the target torque optimization model, and calculates the clutch target engagement pressure through the clutch engagement pressure optimization model;

[0012] Step 3: The host computer's transient control unit sends an output command to the cRIO controller through the transient control model according to the reversible motor target torque and the clutch target engagement pressure. The cRIO controller further transmits the command to the reversible motor and the gearbox to instantaneously coordinate and control the reversible motor output torque and the clutch engagement pressure.

[0013] Step 4: If the actual ship operating conditions change, resulting in a change in the required torque, execute steps 1 to 3 to guide the ship to switch the working mode in the best state under different navigation environment conditions and working conditions.

[0014] Furthermore, in step 2, the target torque optimization model and the clutch engagement pressure optimization model are used to calculate the target torque of the reversible motor and the target engagement pressure of the clutch. Specifically, the following evaluation function is established in the target torque optimization model and the clutch engagement pressure optimization model to quantify the index parameters through three evaluations: Establish an engine speed fluctuation index evaluation function where n e is the original engine speed, n e_tar is the target speed of the engine; the transmission shaft impact index evaluation function is established as where ω v is the angular velocity of the transmission shaft, rad / s; establish the evaluation function of the clutch slip work index Where t1 is the moment when the clutch friction element starts to engage; t2 is the moment when the clutch is completed, T cl is the transmission torque during the clutch slipping process, N·m, ω e ,ω v Angular velocity of the master and slave friction elements, rad / s.

[0015] Furthermore, the coordination optimization decision unit and the instantaneous control unit are analyzed and optimized based on the following squirrel search optimization algorithm:

[0016] Assuming the number of squirrels in the population is N and the dimension is D, the j-dimensional position of the i-th squirrel can be expressed as FS i,j , the positions of all squirrels are Each position parameter corresponds to the target torque of the reversible motor and the target engagement pressure of the clutch during the mode switching process. Each position represents a feasible solution. During the search process, the initial position of the squirrel numbered i is FS i =FS L +U(0,1)×(FS U -FS L ), where FS L and FS U are the lower and upper bounds of the ith squirrel in the jth dimension, respectively. U(0,1) is a uniformly distributed random number in the range [0,1]. It is the convergence factor of the parameters in the algorithm. Swing Factor A random number p between 0 and 1, a constant b and a maximum number of iterations M are initialized and set; when the model is run, the results of different control parameter combinations are evaluated by the established evaluation function, the fitness value of each squirrel individual is calculated and compared, and the position of the squirrel individual with the best fitness value is defined as The individual squirrel position with the best fitness value is defined as The average position of the squirrels is Enter the main algorithm program and update the squirrel's position In the selection process, the best position of the new position and its cross position is compared with the old position to participate in the next generation of population; if the termination condition of the algorithm, that is, the maximum number of iterations, is met, the optimization process ends; otherwise, the optimization process is repeated until the global optimal result is output. The corresponding reversible motor target torque and clutch target engagement pressure are obtained.

[0017] The beneficial effects of the present invention are:

[0018] The optimal motor target torque and clutch engagement pressure when switching working modes of the present invention can not only ensure smooth switching of working modes of the ship, but also reduce engine speed fluctuations and clutch engagement pressure, which can effectively improve the economy and emissions of the ship, while effectively improving the working state of the transmission system when the ship is sailing, and reducing the wear of the gearbox clutch and the engine drive shaft.

[0019] The decision control unit of the present invention performs analysis and calculation through a mathematical model, and the obtained calculation result has high reliability.

[0020] The system of the present invention has strong working stability, the working environment of the system equipment does not have harsh conditions, and the external environment has little impact on the system.

[0021] The present invention can efficiently switch between a variety of operating modes according to the actual operating conditions of the powered ship, effectively improving the efficiency of the ship's hybrid power system, reducing the time the engine works in a low-efficiency area, effectively reducing the engine's fuel consumption, improving the economy and emissions of the ship, and alleviating the contradiction between immature technology and increasingly stringent emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the system structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the method principle of the present invention;

[0024] Figure 3 It is an overall schematic diagram of the present invention.

[0025] The reference numerals of the figures are: 1—engine, 2—reversible motor, 3—AC / DC device, 4—battery pack, 5—gearbox, 6—clutch a, 7—clutch b, 8—propeller, 9—torque sensor, 10—pressure sensor, 11—shaft tachometer, 12—cRIO controller, 13—acquisition card, 14—host computer. DETAILED DESCRIPTION

[0026] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0027] Example 1

[0028] Reference Figure 1 As shown, a parallel hybrid ship transient control system disclosed in the present invention includes a propeller 8 and a gearbox 5, wherein the gearbox 5 is composed of a clutch a6, a clutch b7, and a gear located between the clutch a6 and the clutch b7 and connected to the propeller 8, wherein the clutch a6 is sequentially connected to the engine 1 and the CAN bus, and further includes a cRIO controller 12 with an acquisition card 13 connected to the CAN bus and a touch screen-based PC-side host computer 14 connected to the cRIO controller 12, wherein the clutch b7 is sequentially connected to a torque sensor 9, a shaft speed meter 11, a reversible motor 2, an AC / DC device 3, a battery pack 4, and the CAN bus, wherein the The torque sensor 9 is installed between the reversible motor 2 and the gearbox 5. The torque sensor 9 is used to collect the output torque of the reversible motor 2 and transmit it to the acquisition card 13 of the cRIO controller 12 through the CAN bus; the shaft speed meter 11 is installed on the output shaft of the reversible motor 2. The shaft speed meter 11 is used to collect the rotation speed of the reversible motor 2 and transmit it to the acquisition card 13 of the cRIO controller 12 through the CAN bus; the clutch a6 and the clutch b7 are both provided with a pressure sensor 10. The pressure sensor 10 is used to collect the oil pressure of the clutch a6 and the clutch b7 in the gearbox 5, and transmit it to the acquisition card 13 of the cRIO controller 12 through the CAN bus.

[0029] The acquisition card 13 acquires the engine speed and output torque in the controller ECU of the engine 1 through the CAN bus, and acquires the battery SOC value in the BMS of the battery pack 4 through the CAN bus. The acquisition card 13 further transmits the reversible motor output torque, clutch oil pressure, reversible motor speed, engine speed and output torque, and battery SOC value to the above-mentioned host computer 14 through the CAN bus.

[0030] In addition to communicating with the torque sensor 9, the pressure sensor 10 and the shaft speed meter 11 through the CAN bus, the cRIO controller 12 of the present invention is also connected and communicated with the controller ECU of the engine 1, the controller of the reversible motor 2, the controller of the gearbox 5, the AC / DC device 3 and the BMS of the battery pack 4 to collect data and perform transient control on the parallel hybrid ship transient control system. In the present invention, the host computer 14 communicates with the CRIO rapid simulation prototype controller, and the torque sensor 9 and the pressure sensor 10 transmit the speed, torque and pressure data to the CRIO rapid simulation prototype controller through the CAN bus.

[0031] The host computer 14 of the present invention includes a coordination optimization decision unit and an instantaneous control unit.

[0032] The coordinated optimization decision unit is based on the squirrel search optimization algorithm, and analyzes and optimizes the collected engine output torque, reversible motor output torque, and clutch engagement pressure according to the required torque of the actual ship operating conditions and under the battery SOC value restriction condition to obtain the reversible motor target torque and clutch target engagement pressure.

[0033] The instantaneous control unit controls the reversible motor 2 to complete torque adjustment and the gearbox 5 to complete clutch engagement pressure adjustment according to the power equipment adjustment action signal from the coordinated optimization decision unit, that is, the reversible motor target torque and clutch target engagement pressure optimized by the host computer 14.

[0034] Example 2

[0035] Reference Figure 2 , Figure 3 As shown, the present invention discloses a control method for a parallel hybrid ship transient control system, which includes the following steps.

[0036] Step 1, the data acquisition and transmission unit obtains the required torque of the control system, the output torque and speed of the reversible motor 2, the engagement pressure of the clutch a6 / clutch b7, the output torque and speed of the engine 1, and the battery SOC value of the battery pack 4, and transmits them to the host computer 14.

[0037] Step 2, determine whether the ship system working mode switching rules are met. If the switching rules are met, the coordination optimization decision unit of the host computer 14 calculates the reversible motor target torque through the target torque optimization model, and calculates the clutch target engagement pressure through the clutch engagement pressure optimization model.

[0038] Preferably, in step 2, the target torque of the reversible motor and the target clutch engagement pressure are calculated by the target torque optimization model and the clutch engagement pressure optimization model as follows.

[0039] The optimal reversible motor torque and clutch engagement pressure of the parallel hybrid ship during the switching process of different working modes can reduce the engine speed fluctuation and improve the working condition of the transmission system during the switching process.

[0040] The optimization model in this step is based on the principle of optimizing the engine operating efficiency. The ship parallel hybrid power system mode is designed. The mode switching rules are based on the required torque and battery SOC value. The evaluation function of the mode switching process is established according to the engine speed fluctuation, transmission shaft impact degree, and clutch slip work. The control parameters of the mode switching process, the target torque of the motor and the engagement pressure of the clutch are optimized by the optimization method, and the reversible motor target torque and clutch target engagement pressure are output.

[0041] The following evaluation function is established in the target torque optimization model and the clutch engagement pressure optimization model to quantify the index parameters through three evaluations.

[0042] (1) Engine speed fluctuation evaluation index, the calculation function is: where n e is the original engine speed, n e_tar is the target engine speed.

[0043] (2) Transmission shaft impact evaluation index, the calculation function is: where ω v is the angular velocity of the transmission shaft, rad / s.

[0044] (3) Clutch slip work evaluation index, the calculation function is: Where t1 is the moment when the clutch friction element starts to engage; t2 is the moment when the clutch is completed, T cl is the transmission torque during the clutch slipping process, N·m; ω e ,ω v Angular velocity of the master and slave friction elements, rad / s.

[0045] Step 3, the instantaneous control unit of the host computer 14 sends an output instruction to the cRIO controller 12 through the instantaneous control model according to the target torque of the reversible motor and the target engagement pressure of the clutch. The cRIO controller 12 further transmits the instruction to the controller MCU of the reversible motor 2 and the controller of the gearbox 5 to instantaneously coordinate and control the output torque of the reversible motor and the clutch engagement pressure.

[0046] Step 4: If the actual ship operating conditions change and the required torque changes, execute steps 1 to 3 to control the ship to switch the working mode in the best state under different navigation environment conditions and working conditions.

[0047] The coordination optimization decision unit and the instantaneous control unit are analyzed and optimized based on the following squirrel search optimization algorithm:

[0048] Assuming the number of squirrels in the population is N and the dimension is D, the j-dimensional position of the i-th squirrel can be expressed as FS i,j , the positions of all squirrels are Each position parameter corresponds to the target torque of the reversible motor and the target engagement pressure of the clutch during the mode switching process. Each position represents a feasible solution. During the search process, the initial position of the squirrel numbered i is FS i =FS L +U(0,1)×(FS U -FS L ), where FS L and FS U are the lower and upper bounds of the ith squirrel in the jth dimension, respectively. U(0,1) is a uniformly distributed random number in the range [0,1]. It is the convergence factor of the parameters in the algorithm. Swing Factor A random number p between 0 and 1, a constant b and a maximum number of iterations M are initialized and set; the parameters differential weight F, crossover probability CR and maximum number of iterations M in the algorithm are initialized and set.

[0049] When running the model, the results of different control parameter combinations are evaluated through the established evaluation function, the fitness value of each squirrel individual is calculated and compared, and the position of the squirrel individual with the best fitness value is defined as The individual squirrel position with the best fitness value is defined as The average position of the squirrels is Enter the main algorithm program and update the squirrel's position In the selection process, the best position of the new position and its cross position is compared with the old position to participate in the next generation of population; if the termination condition of the algorithm, that is, the maximum number of iterations, is met, the optimization process ends; otherwise, the optimization process is repeated until the global optimal result is output. The corresponding reversible motor target torque and clutch target engagement pressure are obtained.

[0050] By collecting and monitoring data and adopting the formulated mode switching control rules, when the operating conditions of the hybrid power system change and meet the mode switching conditions, in the different mode switching processes of the parallel hybrid ship, according to the required torque during ship operation and the value of the power battery SOC, the motor output torque and the clutch engagement pressure are used as optimization variables, and the squirrel search optimization algorithm is adopted for optimization calculation. Through the calculated reversible motor target output torque and clutch target engagement pressure, the reversible motor and gearbox are instantaneously coordinated and controlled, thereby achieving an optimized switching process.

[0051] During the switching process of different modes, the host computer instantaneously coordinates and controls the motor target torque and clutch engagement pressure according to the required torque and power battery SOC value during ship operation, so as to optimize the switching process, reduce the engine speed fluctuation and improve the working condition of the transmission system, and ensure the safe, smooth and fast switching of the system working mode; the system collects the ship's motor output torque, speed, gearbox clutch engagement pressure and other operating data in real time through the data acquisition unit; after obtaining the data, the collected data is substituted into the coordination optimization decision unit with the help of the data transmission unit, and the reversible motor target torque and clutch engagement pressure are calculated based on the optimization model; finally, the cRIO controller in the instantaneous control unit further transmits the instructions to the reversible motor controller and gearbox controller, guiding the ship to switch the working mode in the best state under different navigation environment conditions and working conditions, effectively reducing the engine speed fluctuation during the mode switching process, making the power transmission of the hybrid system smooth and improving the working conditions of the transmission system.

[0052] The optimization model of the present invention is based on the principle of optimizing engine operating efficiency. A mode switching rule of a ship parallel hybrid power ship system mode is designed based on the required torque and battery SOC value. An evaluation function of the mode switching process is established according to engine speed fluctuation, transmission shaft impact degree, and clutch slip work. The control parameters of the mode switching process, namely the target torque of the motor and the engagement pressure of the clutch, are optimized by an optimization method, and the reversible motor target torque and the clutch target engagement pressure are output.

[0053] The control method of the present invention has a simple structure and is applicable to existing parallel hybrid ships. It can ensure that the ship switches the working mode smoothly, reduce the engine speed fluctuation and clutch engagement pressure, effectively improve the economy and emissions of the ship, and reduce the wear of the gearbox clutch and the engine transmission shaft, effectively improve the working state of the transmission system during the ship's navigation, and improve the economy and emissions of the ship.

[0054] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A parallel hybrid ship transient control system, characterized by: The invention comprises a propeller (8) and a gearbox (5), wherein the gearbox (5) is composed of a clutch a (6), a clutch b (7) and a gear connected to the propeller (8), wherein the clutch a (6) is connected to an engine (1) and a CAN bus in sequence, and the clutch b (7) is connected to a torque sensor (9), a shaft speed meter (11), a reversible motor (2), an AC / DC device (3), a battery pack (4) and the CAN bus in sequence, and further comprises a cRIO controller (12) with an acquisition card (13) connected to the CAN bus and a host connected to the cRIO controller (12). The invention relates to a machine (14), wherein the clutch a (6) and the clutch b (7) are both provided with a pressure sensor (10), the torque sensor (9) collects the output torque of the reversible motor (2) and transmits it to the acquisition card (13) via a CAN bus, the pressure sensor (10) collects the oil pressure of the clutch a (6) and the clutch b (7) and transmits it to the acquisition card (13) via a CAN bus, the shaft speed meter (11) collects the rotation speed of the reversible motor (2) and transmits it to the acquisition card (13) via a CAN bus, and the acquisition card (13) collects the SOC value of the battery pack (4) via the CAN bus.

2. A parallel hybrid ship transient control system according to claim 1, characterized in that: The torque sensor (9) is installed between the reversible motor (2) and the gear box (5); the shaft speed meter (11) is installed on the output shaft of the reversible motor (2).

3. A parallel hybrid ship transient control system according to claim 2, characterized in that: The host computer (14) includes a coordinated optimization decision unit and an instantaneous control unit; the coordinated optimization decision unit analyzes and optimizes the collected engine output torque, reversible motor output torque, and clutch engagement pressure based on the squirrel search optimization algorithm, according to the required torque, under the condition of the battery SOC value restriction, to obtain the reversible motor target torque and the clutch target engagement pressure; the instantaneous control unit controls the reversible motor (2) to complete the torque adjustment and the gearbox (5) to complete the clutch engagement pressure adjustment according to the power equipment adjustment action signal of the coordinated optimization decision unit based on the squirrel search optimization algorithm.

4. A control method for a parallel hybrid ship transient control system as claimed in claim 1, characterized in that: The following steps are involved: Step 1, obtaining the required torque of the control system, the output torque and speed of the reversible motor (2), the engagement pressure of the clutch a (6) / clutch b (7), the output torque and speed of the engine (1), and the battery SOC value of the battery pack (4), and transmitting them to the host computer (14); Step 2: When the switching rule is met, the coordinated optimization decision unit calculates the target torque of the reversible motor through the target torque optimization model, and calculates the target clutch engagement pressure through the clutch engagement pressure optimization model; Step 3, the instantaneous control unit sends an output command to the cRIO controller (12) through the instantaneous control model according to the target torque of the reversible motor and the target engagement pressure of the clutch, and the cRIO controller (12) further transmits the command to the reversible motor (2) and the gearbox (5), and instantaneously coordinates and controls the output torque of the reversible motor and the engagement pressure of the clutch; Step 4: If the actual ship operating conditions change, execute steps 1 to 3 to control the ship to switch the working mode in the best state.

5. The control method of a parallel hybrid ship transient control system according to claim 4, characterized in that: In the step 2, the target torque optimization model and the clutch engagement pressure optimization model establish the following evaluation function to quantify the index parameters: Establish an engine speed fluctuation index evaluation function where n e is the original engine speed, n e_tar is the target speed of the engine; the transmission shaft impact index evaluation function is established as where ω v is the angular velocity of the transmission shaft; establish the evaluation function of the clutch slip work index Where t1 is the moment when the clutch friction element starts to engage, t2 is the moment when the clutch is completed, T cl is the transmission torque during the clutch slipping process, ω e ,ω v The angular velocity of the master and slave friction elements.

6. The control method of a parallel hybrid ship transient control system according to claim 5, characterized in that: The coordination optimization decision unit and the instantaneous control unit are analyzed and optimized based on the following squirrel search optimization algorithm: Assume that the number of squirrels in the population is N, the dimension is D, and the j-dimensional position of the i-th squirrel is represented by FS i,j , the positions of all squirrels are Each position parameter corresponds to the target torque of the reversible motor and the target engagement pressure of the clutch during the mode switching process. During the search process, the initial position of the squirrel numbered i is FS i =FS L +U(0,1)×(FS U -FS L ), where FS L and FS U are the lower and upper bounds of the ith squirrel in the jth dimension, respectively. U(0,1) is a uniformly distributed random number in the range [0,1]. It is the convergence factor of the parameters in the algorithm. Swing Factor A random number p between 0 and 1, a constant b and a maximum number of iterations M are initialized; The individual squirrel position with the best fitness value is defined as The individual squirrel position with the best fitness value is defined as The average position of the squirrels is Update the squirrel's position In the selection process, the best position of the new position and its cross position is compared with the old position to participate in the next generation of population; if the termination condition of the algorithm, that is, the maximum number of iterations, is met, the optimization process ends; otherwise, the optimization process is repeated until the global optimal result is output. The corresponding reversible motor target torque and clutch target engagement pressure are obtained.

Images