A mode control method for a marine hybrid power system based on energy-saving design

Abstract

The present application discloses a mode control method for a ship hybrid power system based on energy-saving design, which relates to the field of ship technology. The method obtains a power fuel consumption function according to the working characteristics of the hybrid power system, so that the output power of the driving main engine and the diesel engine that minimizes fuel consumption at the real-time speed can be obtained based on the power fuel consumption function, so that the working mode of the hybrid power system can be reasonably selected and switched for the purpose of energy saving. Moreover, the method can organically integrate multiple working modes of the hybrid power system. Through automatic selection by the system instead of relying on manual experience, the control of the working mode of the hybrid power system is more reasonable, more intelligent, and more conducive to the economic performance of the ship.

Description

Technical Field

[0001] The present application relates to the field of ship technology, and in particular to a mode control method for a ship hybrid power system based on energy-saving design. Background Art

[0002] At present, many ships use hybrid power systems based on shaft-driven generators (PTO) to supply energy, which can achieve energy saving and improve economic efficiency. The typical configuration of a hybrid power system with a shaft-driven generator is: the drive main engine is connected to the input end of a single-input dual-output gearbox, one output end of the gearbox is connected to the shaft system and the adjustable propeller to propel the ship, and the other output end of the gearbox is connected to the shaft-driven generator, which can supply power to the entire ship power grid after rectification by the frequency converter. At the same time, the ship is equipped with a generator set consisting of a diesel engine and a generator set, which can also supply power to the entire ship power grid.

[0003] The above hybrid power system has three main working modes: (1) The shaft belt generator is disengaged, the main engine drives only the adjustable propeller through the gearbox, and the generator set alone supplies power to the entire ship's power grid. (2) The shaft belt generator is combined, the main engine drives the adjustable propeller and the shaft belt generator through the gearbox, the generator set does not work, and the shaft belt generator alone supplies power to the entire ship's power grid. (3) The shaft belt generator is combined, the main engine drives the adjustable propeller and the shaft belt generator through the gearbox, the generator set also works, and the shaft belt generator and the generator set jointly supply power to the entire ship's power grid.

[0004] At present, the hybrid power system's operating mode is mainly selected by the operator based on experience, and the operating modes are switched. This is relatively dependent on manual experience and operation. The selected operating mode may not be suitable for the ship's current operating conditions, resulting in the hybrid power system's performance not being fully utilized. Summary of the invention

[0005] In view of the above problems and technical requirements, the applicant has proposed a mode control method for a marine hybrid power system based on energy-saving design. The technical solution of this application is as follows:

[0006] A mode control method for a ship hybrid power system based on energy-saving design comprises the following steps:

[0007] Determine the shaft power P of the adjustable propeller at the ship's real speed s Substitute it into the power fuel consumption function of the hybrid system. The power fuel consumption function reflects the total fuel consumption per unit time G of the ship and the shaft power P of the adjustable propeller s And the output power P of the driving host of the hybrid system i The functional relationship between

[0008] Determine the target output power P of the main drive unit that minimizes the total fuel consumption per unit time G i_target ;

[0009] According to the target output power P of the driving host i_target Based on the energy conservation relationship of the hybrid power system, the target output power P of the diesel engine in the generator set is determined E_target ;

[0010] Control the drive host in the hybrid system according to the target output power P i_target To work, control the diesel engine in the generator set to output power P according to the target E_target Work and output power P according to the target i_target and shaft power P s Control the shaft generator of the hybrid system to disengage or engage;

[0011] Among them, the power-fuel consumption function is obtained by fitting based on the universal characteristics of the driving host, the universal characteristics of the diesel engine and the energy conservation relationship of the hybrid power system.

[0012] A further technical solution is to use the target output power P i_target and shaft power P s The methods for controlling the shaft generator to be disconnected or connected include:

[0013] When P i_target ×η1>P s When the shaft belt generator is controlled to work together, the main engine is driven through the gear box to drive the shaft belt generator and the adjustable propeller to work at the same time;

[0014] When P i_target ×η1=P s When the control shaft is disconnected from the generator, the main engine is driven through the gear box to drive only the adjustable propeller to work;

[0015] Among them, η1 is the conversion efficiency of the gearbox.

[0016] A further technical solution is to determine the target output power P of the driving main engine that minimizes the total fuel consumption per unit time G. i_target include:

[0017] According to the energy conservation relationship of the hybrid power system, the power range of the output power of the driving host is determined [P min ,P max ];

[0018] Determine the power range [P min ,P max The target output power P of the driving main engine that minimizes the total fuel consumption per unit time G within ] i_target .

[0019] A further technical solution is to determine the power range of the output power of the driving host [P min ,P max ] methods include:

[0020] Combined with the output power of the drive host P i Not exceeding the rated power P of the drive host r The first constraint P i ≤P r , output power P of the driving host i Not less than the minimum stable speed n of the driving host min The corresponding power P n_min The second constraint P i ≥P n_min , output power P of the driving host i Satisfy shaft power P s The third constraint P i ≥P s / η1, and ensure the output power P of the diesel engine E The fourth constraint P is not less than 0 E ≥0, find the power range of the output power of the drive host [P min ,P max ].

[0021] A further technical solution is that the method for fitting the power and fuel consumption function of the hybrid power system includes:

[0022] Determine the total fuel consumption per unit time G of the main drive based on the universal characteristics of the main drive i The output power P of the drive host i The functional relationship between G i =h1(P i );

[0023] Determine the total fuel consumption per unit time G of a diesel engine based on its universal characteristics E The output power P of the diesel engine E The functional relationship between E =h2(P E );

[0024] According to the energy conservation relationship of the hybrid power system, the power conversion function P of the hybrid power system is obtained by fitting. E =h3(P s ,P i ), power conversion function P E =h3(P s ,P i ) is used to reflect the output power P of the diesel engine in the generator set EWith adjustable propeller shaft power P s And the output power P of the driving host i The functional relationship between

[0025] Determine the total fuel consumption per unit time of the ship G = G i +G E , and combined with G i =h1(P i ), G E =h2(P E ), P E =h3(P s ,P i ) to obtain the power fuel consumption function of the hybrid system G = H (P s ,P i ).

[0026] A further technical solution is that the energy conservation relationship of the hybrid power system includes:

[0027] The total power output of the main engine through the gearbox and the shaft power P of the adjustable propeller s and the shaft generator input power P t equal;

[0028] And the shaft generator at input power P t The power P provided to the whole ship power grid j With diesel engine output power P E The sum of the electric powers supplied to the whole ship's power grid is equal to the total electric power C of the whole ship's power grid.

[0029] A further technical solution is to fit the power conversion function P of the hybrid system E =h3(P s ,P i ) methods include:

[0030] According to the energy conservation relationship of hybrid power system The power conversion function of the hybrid system is obtained by fitting:

[0031] Among them, η1 is the efficiency of the gearbox, η2 is the efficiency of the shaft generator converted into electrical energy, η3 is the efficiency of the inverter, and η4 is the efficiency of the diesel engine in the generator set converted into electrical energy; P i ×η1 is the total power output of the driving host through the gearbox, P E ×η4 is the diesel engine output power P E The electrical power provided to the entire ship's power grid.

[0032] A further technical solution is to determine G based on the universal characteristics of the driving host.i =h1(P i ) methods include:

[0033] Determine the unit power fuel consumption rate g of the drive host at rated speed based on the universal characteristics of the drive host i The output power P of the drive host i The functional relationship between i =s1(P i );

[0034] Determine the total fuel consumption per unit time G of the drive host i =P i ×g i , and combined with g i =s1(P i ) to get G i =P i ×g i =P i ×s1(P i )=h1(P i ).

[0035] A further technical solution is to determine G based on the universal characteristics of the diesel engine. E =h2(P E ) methods include:

[0036] Determine the unit power fuel consumption rate g of a diesel engine at rated speed based on the universal characteristics of the diesel engine E The output power P of the diesel engine E The functional relationship between E =s2(P E );

[0037] Determine the total fuel consumption per unit time G of the diesel engine E =P E ×g E , and combined with g E =s2(P E ) to get G E =P E ×g E =P E ×s2(P E )=h2(P E ).

[0038] A further technical solution is to determine the target output power P of the diesel engine in the generator set. E_target The methods include:

[0039] The shaft power P of the adjustable propeller corresponding to the real-time speed s and the target output power P of the driving host i_targetSubstitute the power conversion function P of the hybrid system into E =h3(P s ,P i ), calculate the target output power P of the diesel engine in the generator set E_target .

[0040] The beneficial technical effects of this application are:

[0041] The present application discloses a mode control method for a ship hybrid power system based on energy-saving design. The method obtains a power fuel consumption function according to the structure and working characteristics of the hybrid power system, so that the output power of the driving main engine and the diesel engine that minimizes fuel consumption at the real-time speed can be obtained according to the power fuel consumption function, so that the working mode of the hybrid power system can be reasonably selected and switched for the purpose of energy saving. Moreover, the method can organically integrate multiple working modes of the hybrid power system. Through automatic selection by the system instead of relying on manual experience, the control of the working mode of the hybrid power system is more reasonable, more intelligent, and more conducive to the economic performance of the ship. The method also integrates the power supply system and the main propulsion remote control system of the ship implemented by the hybrid power system to achieve centralized control. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a structural schematic diagram of a hybrid power system in one embodiment of the present application and a power schematic diagram of each part.

[0043] Figure 2 It is a method flow chart of a mode control method in one embodiment of the present application.

[0044] Figure 3 It is a schematic diagram of controlling a shaft generator to switch modes in one embodiment of the present application.

[0045] Figure 4 It is a logical relationship diagram for fitting the power and fuel consumption function of the hybrid power system and obtaining the target power of the driving main engine and the diesel engine in one embodiment of the present application.

[0046] Figure 5 It is a graph of the universal characteristics of a driving host in an example.

[0047] Figure 6 It is a graph of the universal characteristics of a diesel engine in an example. DETAILED DESCRIPTION

[0048] The specific implementation of the present application is further described below in conjunction with the accompanying drawings.

[0049] This application discloses a mode control method for a marine hybrid power system based on energy-saving design. Figure 1The structural diagram of the ship hybrid power system shown, and Figure 2 The method comprises the following steps:

[0050] Step S1, determining the shaft power P of the adjustable propeller at the real-time speed V of the ship s Substitute the power fuel consumption function G = H(P s ,P i ).

[0051] Power fuel consumption function G = H (P s ,P i ) reflects the total fuel consumption per unit time G of the ship and the shaft power P of the adjustable propeller s And the output power P of the driving host of the hybrid system i The power-fuel consumption function G=H(P s ,P i ) is obtained based on the universal characteristics of the driving host, the universal characteristics of the diesel engine and the energy conservation relationship of the hybrid power system.

[0052] In one embodiment, the power consumption function G of the hybrid system is obtained by fitting: s ,P i ) methods include, please refer to Figure 4 :

[0053] (1) Determine the total fuel consumption per unit time G of the main engine based on the universal characteristics of the main engine i The output power P of the drive host i The functional relationship between i =h1(P i ). In a hybrid system, the drive main engine usually operates at its rated speed n i_r , and then the speed of the ship is adjusted by changing the pitch of the adjustable propeller. Therefore, based on the universal characteristics of the main engine, the speed of the main engine at the rated speed n can be directly determined. i_r Unit power fuel consumption rate g i The output power P of the drive host i The functional relationship between i =s1(P i ).

[0054] Since the total fuel consumption per unit time of the driving main engine is G i =P i ×g i , so combined with g i =s1(P i ) can get G i =P i ×g i=P i ×s1(P i )=h1(P i ).

[0055] (2) Determine the total fuel consumption per unit time G of the diesel engine based on the universal characteristics of the diesel engine E The output power P of the diesel engine E The functional relationship between E =h2(P E ). Similarly, in a hybrid system, the diesel engine usually operates at its rated speed n E_r Therefore, based on the universal characteristics of the diesel engine, the unit power fuel consumption rate g of the diesel engine at rated speed can be directly determined. E The output power P of the diesel engine E The functional relationship between E =s2(P E ). Since the total fuel consumption per unit time of the diesel engine is G E =P E ×g E , so combined with g E =s2(P E ) can get G E =P E ×g E =P E ×s2(P E )=h2(P E ).

[0056] (3) According to the energy conservation relationship of the hybrid power system, the power conversion function P of the hybrid power system can be fitted E =h3(P s ,P i ), the power conversion function P E =h3(P s ,P i ) is used to reflect the output power P of the diesel engine in the generator set E With adjustable propeller shaft power P s And the output power P of the driving host i The functional relationship between them.

[0057] The energy conservation relationship of the hybrid system includes two parts: (a) the total power output of the main engine through the gearbox and the shaft power P of the adjustable propeller. s and the shaft generator input power P t The total power output of the driving host through the gearbox can be expressed as P i ×η1, η1 is the efficiency of the gearbox. (b) The shaft generator has an input power of P tThe power P provided to the whole ship power grid j With diesel engine output power P E The sum of the electric power provided to the whole ship power grid is equal to the total power consumption C of the whole ship power grid. The diesel engine output power P E The electric power provided to the whole ship power grid can be expressed as P E ×η4, η4 is the efficiency of converting the mechanical work of the diesel engine in the generator set into electrical energy.

[0058] Therefore, it can be determined that the energy conservation relationship of the hybrid system can be expressed as Among them, η2 is the efficiency of the shaft belt generator converted into electrical energy, and η3 is the efficiency of the inverter. From this, the power conversion function of the hybrid system can be obtained as follows: Among them, η1, η2, η3 and η4 are all fixed and known parameters. The total power consumption C of the entire ship's power grid is a constant for the daily power consumption of the ship, which can be obtained by statistical evaluation in advance.

[0059] (4) Determine the total fuel consumption per unit time of the ship G = G i +G E , and combined with G i =h1(P i ), G E =h2(P E ), P E =h3(P s ,P i ) to obtain the power fuel consumption function of the hybrid system G = H (P s ,P i ). Thus, we can get the power-fuel consumption function G=H(P s ,P i ) can be expressed as:

[0060]

[0061] The speed of the ship and the shaft power P of the adjustable propeller s The relationship between can be determined by numerical simulation or model tank test. Therefore, the shaft power P of the adjustable propeller at the real-time speed V can be determined. s , substitute the power fuel consumption function G = H (P s ,P i ) can be obtained by calculating the total fuel consumption per unit time G of the ship at the real-time speed and the output power P of the main engine driven by it. i The functional relationship affected by this single independent variable.

[0062] Step S2: determine the target output power P of the main drive unit that minimizes the total fuel consumption per unit time G. i_target In practical applications, the output power P of the drive hosti It is often not possible to take values ​​within the full power range, so first of all, it is necessary to determine the power range of the output power of the drive host [P min ,P max ], then in the power range [P min ,P max ] Take the output power of the driving main engine that minimizes the total fuel consumption per unit time G as the target output power P i_target In addition, the minimum total fuel consumption per unit time G of the ship can also be directly obtained.

[0063] In one embodiment, the power range of the output power of the driving host is determined according to the energy conservation relationship of the hybrid power system. min ,P max ], including obtaining the power range of the output power of the driving host under the common constraints of the following four constraints [P min ,P max ]:

[0064] (a) The first constraint P i ≤P r , that is, the output power P of the driving host i To ensure that the rated power P of the drive host is not exceeded r .

[0065] (b) The second constraint P i ≥P n_min , that is, the output power P of the driving host i To ensure that the constant speed is not less than the minimum stable speed n of the drive host min The corresponding power P n_min .

[0066] (c) The third constraint P i ≥P s / η1, that is, the total power P output by the driving host through the gearbox i ×η1 must be constant and not less than the shaft power P of the adjustable propeller s .

[0067] (d) The fourth constraint condition P E ≥0, that is, as mentioned above, under the constraint of the energy conservation relationship of the hybrid system, the output power P of the diesel engine E The output power P of the drive host i and the shaft power P of the adjustable propeller s There is a functional relationship P E =h3(P s ,P i ), and also ensure the output power P of the diesel engine E Constantly not less than 0.

[0068] Step S3: according to the target output power P of the driving host i_target Based on the energy conservation relationship of the hybrid power system, the target output power P of the diesel engine in the generator set is determined E_target That is, the shaft power P of the adjustable propeller corresponding to the real-time speed s and the target output power P of the driving host i_target Substitute the power conversion function P of the hybrid system into E =h3(P s ,P i ), calculate the target output power P of the diesel engine in the generator set E_target .

[0069] Step S4: Control the driving host in the hybrid system to output the target power P i_target To work, control the diesel engine in the generator set to output power P according to the target E_target Work and output power P according to the target i_target and shaft power P s Control the shaft generator of the hybrid system to be disengaged or coupled. The methods for controlling the shaft generator to be disengaged or coupled include, please refer to Figure 3 :

[0070] (a) When P i_target ×η1>P s When the total power output of the main engine through the gearbox is greater than the shaft power P of the adjustable propeller s , it means that part of the total power output of the drive main engine through the gearbox is to be provided to the shaft generator, so the shaft generator is controlled to be connected, and the drive main engine drives the shaft generator and the adjustable propeller at the same time through the gearbox. In this case, the input power P of the shaft generator t =P i_target ×η1-P s , the shaft generator has an input power P t The power P provided to the whole ship power grid j =P t ×η2×η3.

[0071] In this case, when P E_target = 0, the shaft generator alone supplies power to the entire ship grid, then C = P j =P t ×η2×η3. When P E_target When >0, the shaft generator and the generator set jointly supply power to the entire ship's power grid.

[0072] (b) When P i_target ×η1=P sWhen the shaft belt generator is disengaged, the main engine is driven through the gear box to drive only the adjustable propeller. In this case, the input power P of the shaft belt generator is t =0, the generator set alone supplies power to the entire ship's power grid.

[0073] Based on the method provided by the present application, in another embodiment, after obtaining the power fuel consumption function G=H(P s ,P i ) and the shaft power P of the ship's adjustable propeller s Functional relationship with speed V s = h4(V), the total fuel consumption per unit time G of the ship, the speed V and the output power P of the driving main engine can be directly obtained i The functional relationship between G=H(h4(V),P i )=Q(V,P i ), based on G=Q(V,P i ) can directly obtain the target output power P of the main engine that minimizes the total fuel consumption per unit time G under different speeds V. i _ target . Also combined with P E =h3(P s ,P i ) can be used to obtain the target output power P of the corresponding diesel engine. E_target , we can directly get the target output power P of the main engine that minimizes the total fuel consumption per unit time G at different speeds. i_target And the corresponding target output power P of the diesel engine E_target Therefore, according to the real-time speed of the ship, P can be directly obtained. i_target and P E_target And determine the minimum total fuel consumption per unit time G at this time, so as to further reduce the amount of real-time calculation.

[0074] In one example, a hybrid power system used in a 3,000-ton scientific research vessel is used as an example. The total length of the vessel is about 90 meters. It is a single engine with a single adjustable propeller, and the output end of the gearbox is connected to a shaft generator. The main engine is driven by a high-speed machine with a rated power of P r The rated speed of the driving host is 3000kW. i_r =2100rpm. The diesel engine of the generator set adopts a high-speed engine with a rated power of 1600kW. The rated speed of the diesel engine is n E_r =1500rpm, the rated power of the shaft generator is 800kW. Take η1=η2=η3=η4=0.95, and take C=500kW. Assume that the minimum stable speed of the drive main engine is n min =Power P corresponding to 600rpm n_min=200kW.

[0075] The universal characteristics of the main drive reflect the unit power fuel consumption rate of the main drive g i With speed n i And the output power P of the driving host i In this example, the universal characteristics of the driver host are as follows Figure 5 The speed of the driving host in the hybrid system is at its rated speed n i_r =2100rpm, the speed is adjusted by the adjustable propeller pitch, so based on the universal characteristics of the main engine, it can be directly determined that the main engine at the rated speed n i_r Unit power fuel consumption rate g i The output power P of the drive host i The functional relationship between i =s1(P i ) = 2 × 10 -05 P i 2 -0.086P i +301.04.

[0076] The universal characteristics of the diesel engine in the generator set reflect the unit power fuel consumption rate of the diesel engine g E With speed n E and the diesel engine output power P E In this example, the universal characteristics of the diesel engine are as follows Figure 6 The speed of the diesel engine in the hybrid system is at its rated speed n E_r =1500rpm, based on the universal characteristics of the diesel engine, it can be directly determined that the diesel engine is at rated speed n E_r Unit power fuel consumption rate g E The output power P of the diesel engine E The functional relationship between E =s2(P E )=5×10 -05 P E 2 -0.1457P E +314.23. So G=P i ×(2×10 -05 P i 2 -0.086P i +301.04)+P E ×(5×10 - 05 P E 2 -0.1457P E+314.23). In this example, the energy conservation relation for the hybrid system is The power conversion function is further obtained as Output power P of the drive host i The constraints that need to be satisfied are

[0077] When the real-time speed is 8 knots, the corresponding adjustable propeller shaft power P s =1000kW, from which we can get the power conversion function as P E ≈1476-0.9P i , further substituting into the power fuel consumption function G = -(329×P i 3 +493660×P i 2 -2224420000×P i -6143277312000) / 20000000. And the output power P of the driving host can be obtained i The power range [P min ,P max ] is [1052kW, 1640kW], and within this power range, the target output power P of the drive host that minimizes G is selected. i_target =1640kW, then the target output power P of the diesel engine can be obtained E_target = 0kW, at this time the ship achieves the minimum total fuel consumption per unit time G = 350618g / h = 351kg / h. In this example, P i_target ×η4=1640kW×0.95=1558kWgreater than P s =1000kW, so the shaft generator is controlled to be connected, and the shaft generator alone supplies power to the entire ship power grid. At this real-time speed, it can be compared in the power range of [1052kW, 1640kW], when the output power P i When the power is 1052 kW, the maximum total fuel consumption per unit time of the ship is 3776991 g / h=378 kg / h. By comparison, it can be seen that the method of the present application can achieve a maximum fuel saving of 7.7%.

[0078] When the real-time speed is 11 knots, the corresponding adjustable propeller shaft power P s =2500kW, and the output power P of the drive host can be obtained by substituting i The power range [P min ,P max ] is [2631kW, 3000kW]. In this case, the specific calculation steps are omitted, and the target output power P of the driving host can be obtained. i_target=2631kW, the ship achieves the minimum total fuel consumption per unit time G = 694kg / h, and the corresponding calculation is P E_target =533kW. In this example, P i_target ×η4=2631kW×0.95=2500kW, so the shaft belt generator is disconnected and the generator set alone supplies power to the entire ship power grid. Under this real-time speed, it can be compared in the power range of [2631kW,3000kW], when the output power P i When the power is 3000 kW, the maximum total fuel consumption per unit time of the ship is 726799 g / h=727 kg / h. By comparison, it can be seen that the method of the present application can achieve a maximum fuel saving of 4.8%.

[0079] Furthermore, the minimum total fuel consumption per unit time P can be calculated according to the above method at different real-time speeds. i_target and P E_target , then the P to be selected can be determined according to the real-time speed i_target and P E_target Control can be carried out and the minimum total fuel consumption per unit time that can be achieved can be determined.

[0080] The above is only a preferred embodiment of the present application, and the present application is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present application should be considered to be included in the protection scope of the present application.

Claims

1. A mode control method for a ship hybrid power system based on energy-saving design, characterized in that: The method comprises: Determine the shaft power P of the adjustable propeller at the ship's real speed s And substitute it into the power fuel consumption function of the hybrid power system, which reflects the total fuel consumption per unit time G of the ship and the shaft power P of the adjustable propeller s And the output power P of the driving host of the hybrid system i The functional relationship between Determine the target output power P of the main drive unit that minimizes the total fuel consumption per unit time G i_target ; According to the target output power P of the driving host i_target The target output power P of the diesel engine in the generator set is determined based on the energy conservation relationship of the hybrid power system. E_target ; Control the driving host in the hybrid system according to the target output power P i_target To work, control the diesel engine in the generator set to output power P according to the target E_target Work, and according to the target output power P i_target and shaft power P s Controlling the shaft generator of the hybrid system to be disengaged or coupled includes: when P i_target ×η1>P s When P is set, the shaft-belt generator is controlled to be in sync, and the main drive unit drives the shaft-belt generator and the adjustable propeller to work simultaneously through the gear box; when P i_target ×η1=P s When the shaft belt generator is disengaged, the driving main engine drives only the adjustable propeller through the gear box; wherein η1 is the conversion efficiency of the gear box; The power fuel consumption function is obtained by fitting based on the universal characteristics of the driving host, the universal characteristics of the diesel engine and the energy conservation relationship of the hybrid power system; the method for fitting the power fuel consumption function of the hybrid power system includes: determining the total fuel consumption per unit time G of the driving host based on the universal characteristics of the driving host i The output power P of the drive host i The functional relationship between i =h1(P i ); Determine the total fuel consumption per unit time G of the diesel engine based on the universal characteristics of the diesel engine E The output power P of the diesel engine E The functional relationship between E =h2(P E );According to the energy conservation relationship of the hybrid power system, the power conversion function P of the hybrid power system is obtained by fitting E =h3(P s ,P i ), the power conversion function P E =h3(P s ,P i ) is used to reflect the output power P of the diesel engine in the generator set E With adjustable propeller shaft power P s And the output power P of the driving host i Determine the total fuel consumption per unit time of the ship G = G i +G E , and combined with G i =h1(P i ), G E =h2(P E ), P E =h3(P s ,P i ) to obtain the power fuel consumption function G = H (P s ,P i ).

2. The method according to claim 1, characterized in that Determine the target output power P of the main drive unit that minimizes the total fuel consumption per unit time G i_target include: The power range of the output power of the driving host is determined according to the energy conservation relationship of the hybrid power system. min ,P max ]; Determine the power range [P min ,P max The target output power P of the driving main engine that minimizes the total fuel consumption per unit time G within ] i_target .

3. The method according to claim 2, characterized in that Determine the power range of the output power of the drive host [P min ,P max ] methods include: Combined with the output power of the drive host P i Not exceeding the rated power P of the drive host r The first constraint P i ≤P r , output power P of the driving host i Not less than the minimum stable speed n of the driving host min The corresponding power P n_min The second constraint P i ≥P n_min , output power P of the driving host i Satisfy shaft power P s The third constraint P i ≥P s / η1, and ensure the output power P of the diesel engine E The fourth constraint P is not less than 0 E ≥0, the power range of the output power of the driving host is obtained [P min ,P max ].

4. The method according to claim 1, characterized in that The energy conservation relationship of the hybrid power system includes: The total power output of the main engine through the gearbox and the shaft power P of the adjustable propeller s and the shaft generator input power P t equal; And the shaft generator at input power P t The power P provided to the whole ship power grid j With diesel engine output power P E The sum of the electric powers supplied to the whole ship's power grid is equal to the total electric power C of the whole ship's power grid.

5. The method according to claim 4, characterized in that The power conversion function P of the hybrid system is obtained by fitting E =h3(P s ,P i ) methods include: According to the energy conservation relationship of the hybrid system The power conversion function of the hybrid system is obtained by fitting: Among them, η1 is the efficiency of the gearbox, η2 is the efficiency of the shaft generator converted into electrical energy, η3 is the efficiency of the inverter, and η4 is the efficiency of the diesel engine in the generator set converted into electrical energy; P i ×η1 is the total power output of the driving host through the gearbox, P E ×η4 is the diesel engine output power P E The electrical power provided to the entire ship's power grid.

6. The method according to claim 1, characterized in that Determine G based on the universal characteristics of the drive host i =h1(P i ) methods include: Based on the universal characteristics of the driving main engine, the unit power fuel consumption rate g of the driving main engine at the rated speed is determined. i The output power P of the drive host i The functional relationship between i =s1(P i ); Determine the total fuel consumption per unit time G of the drive main engine i =P i ×g i , and combined with g i =s1(P i ) to get G i =P i ×g i =P i ×s1(P i )=h1(P i ).

7. The method according to claim 1, characterized in that Determine G based on the universal characteristics of the diesel engine E =h2(P E ) methods include: Based on the universal characteristics of the diesel engine, the unit power fuel consumption rate g of the diesel engine at the rated speed is determined. E The output power P of the diesel engine E The functional relationship between E =s2(P E ); Determine the total fuel consumption per unit time G of the diesel engine E =P E ×g E , and combined with g E =s2(P E ) to get G E =P E ×g E =P E ×s2(P E )=h2(P E ).

8. The method according to claim 1, characterized in that Determine the target output power P of the diesel engine in the generator set E_target The methods include: The shaft power P of the adjustable propeller corresponding to the real-time speed s and the target output power Pi_target of the driving host are substituted into the power conversion function P of the hybrid system E =h3(P s ,P i ), calculate the target output power P of the diesel engine in the generator set E_target .

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