Fuel optimization calculation method and system for ship energy management

Abstract

The invention discloses a fuel optimization calculation method and system for ship energy management, and belongs to the technical field of hybrid power system energy management.The method comprises the steps that the fuel consumption rate of a generator set, the charging and discharging current of a battery and the environment temperature are collected in real time; calculating an instantaneous charge-discharge rate factor of the battery, obtaining a basic attenuation coefficient in combination with a temperature query mapping table, and associating a cycle life model to generate an actual loss rate; when the actual loss rate exceeds a preset threshold value, marking the battery as a high-loss state, determining an accelerated aging life attenuation increment by utilizing a battery aging characteristic curve, and generating a unilateral loss compensation value in combination with replacement cost; converting the unilateral loss compensation value into an equivalent fuel loss amount, and superposing the equivalent fuel loss amount to a fuel consumption rate; and generating a power distribution optimization instruction based on the superposed fuel consumption rate. According to the method, the hidden cost of the battery in a high-loss state is accurately quantified and is taken into an optimization target, and the overall economical efficiency of operation of the ship hybrid power system is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid power system energy management, and in particular to a fuel optimization calculation method and system for ship energy management. Background Art

[0002] In marine hybrid power systems, traditional energy management strategies focus primarily on optimizing the instantaneous fuel consumption of generator sets. These strategies typically view battery charging and discharging as a source of energy with a fixed or negligible cost. However, when batteries are in a high-loss state (e.g., high-current charging and discharging, or in a high-temperature environment), their aging rate accelerates significantly, far exceeding the loss level under normal operating conditions. This accelerated aging leads to a reduction in battery life, resulting in significant hidden costs in long-term operations.

[0003] Existing technologies fail to effectively identify this high-loss state of the battery, and are even more unable to accurately quantify the additional life loss costs caused by exceeding the normal loss threshold and incorporate them into the considerations of real-time energy optimization. Therefore, traditional optimization strategies based on minimizing instantaneous fuel consumption often overuse batteries in high-loss states (because they are seemingly "fuel-efficient"), resulting in an unexpected shortening of battery life, ultimately increasing the overall operating cost of the system, and failing to achieve true global economic optimization. Summary of the Invention

[0004] The present invention provides a fuel optimization calculation method and system for ship energy management, the main purpose of which is to solve the problem of suboptimal overall system operation economy caused by ignoring the hidden costs brought about by accelerated aging of batteries in a high-loss state in hybrid ship energy management.

[0005] To achieve the above objectives, the present invention provides a fuel optimization calculation method for ship energy management, comprising: Real-time collection of fuel consumption rate of generator sets, charge and discharge current of battery packs, and ambient temperature; determining an instantaneous charge and discharge rate factor of the battery pack according to the charge and discharge current, querying a temperature-rate attenuation mapping table of the battery pack based on the instantaneous charge and discharge rate factor and the ambient temperature to output a basic attenuation coefficient, and associating the basic attenuation coefficient with a cycle life model of the battery pack to generate an actual loss rate; When the actual loss rate exceeds a preset loss rate threshold, marking the current battery pack as being in a high loss state; For a battery pack in a high loss state, calculating in real time the positive difference between the actual loss rate and the preset loss rate threshold; mapping the positive difference to an accelerated aging life attenuation increment based on a current-temperature-life attenuation three-dimensional relationship in a battery aging characteristic curve, and multiplying the replacement cost coefficient of the battery pack to generate a one-sided loss compensation value; converting the one-sided loss compensation value to an equivalent fuel loss amount and adding it to the fuel consumption rate, and generating a ship power distribution optimization instruction based on the added fuel consumption rate.

[0006] To solve the above problems, the application also provides a fuel optimization calculation system for ship energy management, which comprises: a data acquisition module for acquiring the fuel consumption rate of the generator set, the charging and discharging current of the battery pack, and the environmental temperature in real time; a battery loss quantification module for determining the instantaneous charging and discharging rate factor of the battery pack according to the charging and discharging current, querying a temperature-rate attenuation mapping table of the battery pack based on the instantaneous charging and discharging rate factor and the environmental temperature to output a basic attenuation coefficient, and correlating the basic attenuation coefficient with a cycle life model of the battery pack to generate an actual loss rate; a high loss state determination module for marking the current battery pack as being in a high loss state when the actual loss rate exceeds a preset loss rate threshold; a loss difference calculation module for calculating a positive difference between the actual loss rate and the preset loss rate threshold in real time for the battery pack in the high loss state; a one-sided loss compensation module for mapping the positive difference to an accelerated aging life attenuation increment based on a current-temperature-life attenuation three-dimensional relationship in a battery aging characteristic curve, and multiplying the replacement cost coefficient of the battery pack to generate a one-sided loss compensation value; a power distribution optimization module for converting the one-sided loss compensation value to an equivalent fuel loss amount and adding it to the fuel consumption rate, and generating a ship power distribution optimization instruction based on the added fuel consumption rate.

[0007] Compared with the prior art, the application has the following beneficial effects: 1. By acquiring key parameters such as the fuel consumption rate of the generator set, the battery charging and discharging current, and the environmental temperature in real time, and accurately calculating the actual loss rate of the battery based on the battery cycle life model, it can effectively identify whether the battery is in a high loss state; on this basis, the positive difference exceeding the preset loss rate threshold is calculated, and the battery aging characteristic curve (reflecting the three-dimensional relationship of current-temperature-life attenuation) is used to accurately map the positive difference to an accelerated aging life attenuation increment, and then the one-sided loss compensation value for only the part exceeding the normal loss is calculated by combining the battery replacement cost coefficient, solving the technical problem that the traditional method cannot accurately quantify the additional loss cost of the battery under abnormal working conditions.

[0008] 2. By converting the single-sided loss compensation value into an equivalent fuel consumption amount and superimposing it on the original fuel consumption rate of the generator set, a new optimization target is constructed that considers both the instantaneous fuel consumption and the implicit aging cost of the battery; based on this superimposed fuel consumption rate, combined with system constraint conditions, power distribution optimization is performed (such as using a quadratic programming algorithm), generating a globally more optimal power distribution instruction, effectively overcoming the limitations of traditional strategies that only focus on instantaneous fuel consumption while ignoring the long-term aging cost of the battery, achieving a collaborative optimization of power distribution for the generator set and the battery pack, significantly improving the overall economy of hybrid ship energy management, and reducing the system's life cycle operating cost. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 A flowchart of a fuel optimization calculation method for ship energy management provided by an embodiment of the present application is shown in the figure. Figure 2 A temperature-rate attenuation mapping table stored in a battery management system provided by an embodiment of the present application is shown in the figure. Figure 3 A functional module diagram of a fuel optimization calculation system for ship energy management provided by an embodiment of the present application is shown in the figure. The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0010] It should be understood that the specific embodiments described herein are merely intended to explain the present application and are not intended to limit the present application.

[0011] An embodiment of the present application provides a fuel optimization calculation method for ship energy management. The execution subject of the fuel optimization calculation method for ship energy management includes but is not limited to at least one of electronic devices such as a server, a terminal, etc., which can be configured to execute the method provided by the embodiment of the present application. In other words, the fuel optimization calculation method for ship energy management can be executed by software or hardware installed in a terminal device or a server device. The server includes but is not limited to a single server, a server cluster, a cloud server, or a cloud server cluster, etc. The server can be a standalone server, or a cloud server providing cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content distribution networks, and big data and artificial intelligence platforms, etc. basic cloud computing services.

[0012] Referring to Figure 1 A flowchart of a fuel optimization calculation method for ship energy management provided by an embodiment of the present application is shown in the figure. In this embodiment, the fuel optimization calculation method for ship energy management includes: S1, collecting fuel consumption rate of the generator set, charging and discharging current of the battery pack and environmental temperature in real time.

[0013] In some embodiments, the collecting fuel consumption rate of the generator set, charging and discharging current of the battery pack and environmental temperature in real time comprises: obtaining real-time fuel flow signal of the diesel generator set through the ship bus interface to generate the fuel consumption rate; collecting charging and discharging current of the lithium ion battery pack through the battery management system; obtaining temperature readings of distributed points in the battery cabin through the temperature sensor array, and taking the highest reading as the environmental temperature.

[0014] In the embodiments of the present application, the fuel consumption rate refers to the mass of fuel consumed by the generator set per unit time; the charging and discharging current refers to the current passing through the battery pack during charging or discharging; and the environmental temperature refers to the highest reading among the temperatures of multiple distributed points in the battery cabin.

[0015] In the embodiments of the present application, the collecting fuel consumption rate of the generator set, charging and discharging current of the battery pack and environmental temperature in real time comprises: Firstly, for the fuel consumption rate of the generator set, the ship bus interface is a communication interface connecting various devices of the ship. When the diesel generator set is running, it will generate real-time fuel flow signal. The signal is transmitted out through the ship bus interface. After the system receives the signal, it is calculated and processed according to the unit time to generate the fuel consumption rate. For example, if the real-time fuel flow signal transmitted by the ship bus interface shows that 0.6 kg of fuel is consumed per minute, then after calculation, the fuel consumption rate is 36 kg per hour.

[0016] Secondly, for the charging and discharging current of the battery pack, the battery management system is a system specially used for managing the battery pack, which contains a current collection module and can monitor the current change of the lithium ion battery pack in the charging and discharging process in real time, so as to collect the charging and discharging current. For example, when the battery pack is in the discharging state, the current collected by the battery management system may be -100A, and the minus sign indicates discharging; when it is in the charging state, the current collected may be 80A.

[0017] Finally, for the environmental temperature, the temperature sensor array is an array composed of multiple temperature sensors, which are distributed at different positions in the battery cabin and can obtain temperature readings of each distributed point respectively. The system processes these readings and selects the highest reading as the environmental temperature. Assuming that the temperature readings obtained by the temperature sensor array at different positions in the battery cabin are 30℃, 32℃, 35℃ and 33℃, then the environmental temperature is determined as 35℃.

[0018] In the embodiments of the present application, the collected fuel consumption rate, charging and discharging current and environmental temperature will be used as the input data for calculating the instantaneous charging and discharging rate factor, basic attenuation coefficient and other parameters in the S2 step, and are the starting data source of the whole fuel optimization calculation process.

[0019] S2, determining the instantaneous charging and discharging rate factor of the battery pack according to the charging and discharging current, querying the basic attenuation coefficient of the temperature-rate attenuation mapping table of the battery pack based on the instantaneous charging and discharging rate factor and the environmental temperature, and generating the actual loss rate by associating the basic attenuation coefficient with the cycle life model of the battery pack.

[0020] In the embodiments of the present application, the instantaneous charging and discharging rate factor refers to the ratio of the absolute value of the charging and discharging current to the rated capacity of the battery pack, and the unit is hour-1; the temperature-rate attenuation mapping table is a two-dimensional lookup table stored in the battery management system, the horizontal axis is the rate factor, the vertical axis is the environmental temperature, and the values in the table are the basic attenuation coefficients between 0 and 1.

[0021] In the embodiments of the present application, the basic attenuation coefficient is a value obtained by querying the temperature-rate attenuation mapping table and used to reflect the attenuation degree of the battery under the current working condition, and the value is between 0 and 1.

[0022] In the embodiments of the present application, the cycle life model is a model used to describe the life attenuation law of the battery pack under different working conditions, and an exponential life attenuation function based on the Arrhenius equation is adopted in the present application; the actual loss rate is a parameter obtained by associating the basic attenuation coefficient with the cycle life model and representing the battery life consumption speed.

[0023] In some embodiments, the determination of the instantaneous charging and discharging rate factor of the battery pack according to the charging and discharging current comprises: obtaining the rated capacity value of the battery pack, dividing the absolute value of the charging and discharging current by the rated capacity value, and outputting the instantaneous charging and discharging rate factor of the battery pack.

[0024] In the embodiments of the present application, the determination of the instantaneous charging and discharging rate factor of the battery pack according to the charging and discharging current comprises: Firstly, the rated capacity value of the battery pack needs to be obtained, which is an inherent parameter of the battery pack and can be obtained from the specification of the battery pack, for example, the rated capacity value of a certain lithium ion battery pack is 200 ampere-hours.

[0025] Then, the charging and discharging current collected in the S1 step is obtained. Since the charging and discharging current has positive and negative, it is positive when charging and negative when discharging, and the rate factor only concerns the size of the current, so the absolute value of the charging and discharging current needs to be taken.

[0026] Finally, the absolute value of the charge and discharge current is divided by the rated capacity value, and the result is the instantaneous charge and discharge rate factor. For example, if the charge and discharge current collected in S1 is -100 amperes (indicating discharge), the absolute value is 100 amperes, and the instantaneous charge and discharge rate factor is 100 amperes divided by 200 ampere-hours, the result is 0.5 reciprocal hours.

[0027] In some embodiments, as shown in FIG. 1, the method comprises: Figure 2 querying a temperature-rate attenuation mapping table based on the instantaneous charge and discharge rate factor and the ambient temperature to output a basic attenuation coefficient, comprising: calling a two-dimensional lookup table stored in the battery management system, wherein the horizontal axis of the two-dimensional lookup table is the rate factor, and the vertical axis is the ambient temperature; using the instantaneous charge and discharge rate factor and the ambient temperature under the current working condition as joint index coordinates to output a basic attenuation coefficient between 0 and 1.

[0028] In the embodiments of the present application, the basic attenuation coefficient is queried from the temperature-rate attenuation mapping table based on the instantaneous charge and discharge rate factor and the ambient temperature, which comprises that the temperature-rate attenuation mapping table is pre-stored in the battery management system, and the table is obtained through a large number of laboratory tests on the same type of battery pack, covering the corresponding basic attenuation coefficients under different combinations of rate factors and ambient temperatures. When querying, the system calls the two-dimensional lookup table, uses the currently calculated instantaneous charge and discharge rate factor as the horizontal axis coordinate, and uses the ambient temperature obtained in step S1 as the vertical axis coordinate. Through the joint index formed by the two coordinates, the corresponding value in the lookup table is found, which is the basic attenuation coefficient.

[0029] For example, if the current instantaneous charge and discharge rate factor is 0.5 reciprocal hours and the ambient temperature is 35 degrees Celsius, the corresponding basic attenuation coefficient in the lookup table is 0.6.

[0030] In some embodiments, the association of the basic attenuation coefficient with the cycle life model of the battery pack to generate the actual loss rate comprises: inputting the basic attenuation coefficient into an exponential life attenuation function constructed based on the Arrhenius equation; combining the number of cycles of the battery pack to cumulatively correct the exponential life attenuation function, and outputting an actual loss rate representing the speed of battery life consumption.

[0031] In the embodiments of the present application, the association of the basic attenuation coefficient with the cycle life model of the battery pack to generate the actual loss rate comprises: First, an exponential life attenuation function is constructed based on the Arrhenius equation, which can be expressed as an exponential relationship between the life attenuation amount and the basic attenuation coefficient, temperature, etc. The function can reflect the influence of temperature on battery aging.

[0032] Then, the base attenuation coefficient obtained in the foregoing is input into the exponential life attenuation function. At the same time, the cycle number of the battery pack needs to be obtained, which can be recorded and stored by the battery management system, for example, the cycle number of a certain battery pack is 500 times.

[0033] Then, the exponential life attenuation function is cumulatively corrected in combination with the cycle number, because the aging of the battery is a cumulative process, and the more the cycle number is, the more the aging degree will be cumulatively affected. Through such processing.

[0034] Finally, the actual loss rate capable of representing the current life consumption speed of the battery is output. For example, after the base attenuation coefficient 0.6 is input into the function and corrected in combination with the cycle number 500 times, the actual loss rate obtained is 0.002 per cycle number.

[0035] In the embodiment of the application, the step realizes quantitative evaluation of the battery loss, solves the problem that the aging degree of the battery under different working conditions cannot be accurately measured in the traditional method, and provides a basis for subsequent judgment of whether the battery is in a high-loss state.

[0036] S3, when the actual loss rate exceeds a preset loss rate threshold, marking that the current battery pack is in a high-loss state.

[0037] In the embodiment of the application, the preset loss rate threshold refers to an upper limit of the loss rate of the battery pack under normal working conditions determined based on historical running data statistics of the ship and verified in combination with a battery specification book; and the high-loss state refers to a state when the actual loss rate of the battery pack continuously exceeds the preset loss rate threshold for a preset time length.

[0038] In some embodiments, when the actual loss rate exceeds the preset loss rate threshold, marking that the current battery pack is in a high-loss state, includes: determining the upper limit of the loss rate of the battery pack under normal working conditions based on historical running data statistics of the ship; verifying the rationality of the upper limit of the loss rate in combination with an accelerated aging critical condition in the battery specification book, and solidifying the verified upper limit of the loss rate as the preset loss rate threshold; continuously comparing the actual loss rate with the preset loss rate threshold, and when the actual loss rate continuously exceeds the preset loss rate threshold for a preset time length, marking the high-loss state of the current battery pack.

[0039] In the embodiment of the present application, the upper limit of the loss rate of the battery pack under normal working conditions is determined based on the ship historical operation database, including: the ship historical operation database stores a large amount of loss rate data of the battery pack in the past operation process of the ship, which covers different routes, different loads, different environmental temperatures and other normal working conditions. The system calls the database and uses statistical analysis method, such as calculating the 95% quantile value of the data, and taking the quantile value as the preliminary upper limit of the loss rate under normal working conditions.

[0040] For example, 1000 sets of normal working condition loss rate data in the database in the past year are counted, and the loss rate corresponding to the 95% quantile value is 0.0015 per cycle, which is the preliminary loss rate upper limit.

[0041] In the embodiment of the present application, the reasonableness of the upper limit of the loss rate is verified in combination with the accelerated aging critical condition in the battery specification book, and is solidified as a preset loss rate threshold, including: the battery specification book clearly records the accelerated aging critical condition of the battery pack under different working conditions, including the aging speed under a certain loss rate. Compare the upper limit of the loss rate obtained by statistics with the accelerated aging critical condition. If the upper limit is lower than the loss rate corresponding to the critical condition, it means that the upper limit is in a safe range and is reasonable; if it is higher, it needs to be lowered below the critical condition. After verification, the loss rate upper limit of 0.0015 per cycle is lower than the 0.002 per cycle corresponding to the accelerated aging critical condition in the specification book, so it is solidified as a preset loss rate threshold.

[0042] In the embodiment of the present application, the actual loss rate is continuously compared with the preset loss rate threshold and marked as a high loss state, including: the actual loss rate calculated in S2 is obtained in real time, and is continuously compared with the preset loss rate threshold. The preset time is set according to the battery characteristics and the ship operation demand, for example, 5 minutes. When the actual loss rate continuously exceeds the preset loss rate threshold for 5 minutes, the system automatically marks that the current battery pack is in a high loss state.

[0043] For example, if the actual loss rate is 0.002 per cycle, the preset loss rate threshold is 0.0015 per cycle, and the state lasts for 5 minutes, the battery pack is marked as a high loss state.

[0044] In the embodiment of the present application, this step can identify the abnormal aging state of the battery pack in time, solve the problem that the traditional method cannot accurately judge whether the battery is in an accelerated aging state, and provide a premise for subsequent loss compensation calculation.

[0045] S4, for the battery pack in the high loss state, the positive difference between the actual loss rate and the preset loss rate threshold is calculated in real time.

[0046] In the embodiments of the present application, the positive difference refers to a positive value obtained by subtracting the preset loss rate threshold from the actual loss rate of the battery pack in the high loss state.

[0047] In the embodiments of the present application, the positive difference between the actual loss rate and the preset loss rate threshold of the battery pack in the high loss state is calculated in real time, comprising: Firstly, the system confirms that the battery pack has been marked as a high loss state, which is a prerequisite for performing the calculation, and the state information comes from the output of step S3.

[0048] Then, the actual loss rate updated continuously in step S2 is obtained in real time, and the preset loss rate threshold solidified in step S3 is called, and the actual loss rate is subtracted from the preset loss rate threshold by using subtraction operation. Since the battery pack is in a high loss state at this time, the actual loss rate is greater than the preset loss rate threshold, so the result obtained is a positive value, which is the positive difference.

[0049] For example, if the current actual loss rate is 0.002 per cycle, and the preset loss rate threshold is 0.0015 per cycle, then by calculating 0.002 minus 0.0015, the positive difference is 0.0005 per cycle. The system will repeat the above data acquisition and calculation process at certain time intervals (such as once every 1 second) to realize the real-time updating of the positive difference.

[0050] In the embodiments of the present application, this step quantifies the part of the battery pack exceeding the normal loss, solves the problem that the degree of excessive loss of the battery cannot be determined in the traditional method, and provides a specific quantitative basis for converting the loss into economic cost in the subsequent step.

[0051] S5, mapping the positive difference into an accelerated aging life attenuation increment based on the current-temperature-life attenuation three-dimensional relationship in the battery aging characteristic curve, and multiplying the replacement cost coefficient of the battery pack to generate a one-way loss compensation value.

[0052] In the embodiments of the present application, the battery aging characteristic curve is a curve describing the life attenuation law of the battery pack under different charging and discharging currents and environmental temperatures; the current-temperature-life attenuation three-dimensional relationship refers to the correlation between the charging and discharging current, the environmental temperature and the battery life attenuation amount; and the accelerated aging life attenuation increment refers to the life attenuation amount of the battery pack generated due to exceeding the normal loss, which is obtained by mapping the positive difference.

[0053] In the embodiments of the present application, the replacement cost coefficient refers to the replacement cost per unit capacity of the battery pack; and the one-way loss compensation value refers to the compensation value for only the part exceeding the normal loss after converting the accelerated aging life attenuation increment into economic cost.

[0054] In some embodiments, the mapping of the positive difference to an accelerated aging life degradation increment based on the current-temperature-life degradation three-dimensional relationship in the battery aging characteristic curve, and multiplying the replacement cost coefficient of the battery pack generates a one-sided loss compensation value, including: In a laboratory environment, the same type of battery pack is subjected to multi-working condition cycle aging test, and the life degradation data under different charge-discharge current-ambient temperature combinations are recorded; Based on the life degradation data, and combined with the least square method, a nonlinear degradation surface with current-temperature two dimensions is generated, wherein the nonlinear degradation surface takes the charge-discharge current under the current working condition as the X-axis coordinate, and the ambient temperature as the Y-axis coordinate; The accelerated aging life degradation increment corresponding to the positive difference is extracted in the nonlinear degradation surface; The accelerated aging life degradation increment is converted into a capacity degradation percentage, and multiplied by the total capacity of the battery pack to obtain an equivalent loss capacity; The equivalent loss capacity is multiplied by the unit capacity replacement cost of the battery pack, and the economic compensation value is output as a one-sided loss compensation value.

[0055] In the embodiments of the present application, the same type of battery pack is subjected to multi-working condition cycle aging test in a laboratory environment and the life degradation data under different charge-discharge current-ambient temperature combinations are recorded, including: selecting the same type of battery pack as the test sample used on the ship, and building a test platform simulating the working environment of the ship battery in the laboratory. The platform can accurately control the charge-discharge current and the ambient temperature. A plurality of different combinations of charge-discharge current (such as 50A, 100A, 150A, etc.) and ambient temperature (such as 25℃, 30℃, 35℃, etc.) are set, and the battery pack is subjected to cycle charge-discharge aging test. During the test, the life degradation data of the battery pack under each working condition is continuously recorded, for example, how much the battery life is degraded after a certain number of cycles under the working condition of charge-discharge current 100A and ambient temperature 35℃. These data will serve as the basis for subsequent construction of a nonlinear degradation surface.

[0056] In the embodiments of the present application, a nonlinear degradation surface with current-temperature two dimensions is generated based on the life degradation data and combined with the least square method, including: collecting all the life degradation data obtained by laboratory test, taking the charge-discharge current as the X-axis coordinate, the ambient temperature as the Y-axis coordinate, and the life degradation as the Z-axis coordinate, and establishing a data point set. The least square method is used to fit these data points to construct a nonlinear degradation surface that can reflect the life degradation law under the current-temperature two dimensions. The surface can output the corresponding life degradation through any given charge-discharge current and ambient temperature.

[0057] For example, when the charge-discharge current is 100 A and the ambient temperature is 35℃, the corresponding life attenuation amount can be obtained from the curved surface.

[0058] In the embodiment of the present application, the accelerated aging life attenuation increment corresponding to the positive difference is extracted in the nonlinear attenuation curved surface, comprising: obtaining the positive difference calculated in S4, and searching in the constructed nonlinear attenuation curved surface in combination with the charge-discharge current and the ambient temperature under the current working condition. Taking the positive difference, the charge-discharge current and the ambient temperature as the retrieval conditions, the life attenuation increment corresponding to them in the curved surface is found, and the increment is the accelerated aging life attenuation increment.

[0059] For example, when the positive difference is 0.0005 per cycle, the charge-discharge current is 100 A, and the ambient temperature is 35℃, the accelerated aging life attenuation increment extracted from the curved surface is 5%.

[0060] In the embodiment of the present application, the accelerated aging life attenuation increment is converted into capacity attenuation percentage and multiplied by the total capacity of the battery pack to obtain the equivalent loss capacity, comprising: according to the characteristics of the battery, the accelerated aging life attenuation increment and the capacity attenuation percentage have a corresponding relationship, for example, the accelerated aging life attenuation increment 5% corresponds to the capacity attenuation percentage 2%. The obtained accelerated aging life attenuation increment is converted into capacity attenuation percentage according to the corresponding relationship, and the total capacity of the battery pack (such as 200 Ah) is obtained. The capacity attenuation percentage is multiplied by the total capacity to obtain the equivalent loss capacity. For example, the capacity attenuation percentage is 2%, and the total capacity is 200 Ah, so the equivalent loss capacity is 200 Ah x 2% = 4 Ah.

[0061] In the embodiment of the present application, the equivalent loss capacity is multiplied by the unit capacity replacement cost of the battery pack to output the economic compensation value as the one-way loss compensation value, comprising: obtaining the unit capacity replacement cost (such as 10 yuan / Ah) of the battery pack, and multiplying the equivalent loss capacity by the unit capacity replacement cost to obtain the economic compensation value, which is also the one-way loss compensation value.

[0062] For example, the equivalent loss capacity is 4 Ah, and the unit capacity replacement cost is 10 yuan / Ah, so the one-way loss compensation value is 4 Ah x 10 yuan / Ah = 40 yuan.

[0063] In the embodiment of the present application, this step quantifies the excessive loss of the battery into specific economic cost, solves the problem that the implicit aging cost of the battery cannot be considered in the energy management in the traditional method, and provides an economic basis for optimizing the ship power distribution.

[0064] S6, convert the one-way loss compensation value into equivalent fuel loss amount and superimpose it to the fuel consumption rate, and generate a ship power distribution optimization instruction based on the superimposed fuel consumption rate.

[0065] In the embodiments of the present application, the equivalent fuel consumption amount refers to fuel quality equivalent in economic cost to the unilateral loss compensation value, which is converted according to the current market price of marine fuel oil and the measured low heat value of the generator set; the superimposed fuel consumption rate refers to the rate obtained by superimposing the equivalent fuel consumption amount on the original fuel consumption rate; and the ship power distribution optimization instruction refers to an instruction generated based on the superimposed fuel consumption rate, which is used to guide the power distribution of the generator set and the battery pack.

[0066] In some embodiments, the conversion of the unilateral loss compensation value into the equivalent fuel consumption amount comprises: obtaining the current market price of marine fuel oil; calculating the consumable fuel quality corresponding to a unit of currency according to the measured low heat value of the generator set and the market price; dividing the unilateral loss compensation value by the consumable fuel quality corresponding to the unit of currency to generate the equivalent fuel consumption amount for cost optimization.

[0067] In the embodiments of the present application, the market price of marine fuel oil refers to the unit mass price of the fuel oil on the current market; the measured low heat value of the generator set refers to the heat released when the fuel oil used by the generator set is completely combusted, which is obtained by actual measurement; and the consumable fuel quality corresponding to a unit of currency refers to the fuel quality that can be purchased per unit of currency.

[0068] In some embodiments, the generation of the ship power distribution optimization instruction based on the superimposed fuel consumption rate comprises: establishing an optimization model with the superimposed fuel consumption rate as the objective function; adding the power limit value of the generator set and the safety range of the battery pack as constraint conditions; solving the optimal power distribution instruction set of the generator set and the battery pack by a quadratic programming algorithm.

[0069] In the embodiments of the present application, the optimization model is a mathematical model with the superimposed fuel consumption rate as the objective function and the power limit value of the generator set and the safety range of the battery pack as constraint conditions; and the power limit value of the generator set refers to the maximum power range that the generator set can reach under the premise of safe and stable operation.

[0070] In the embodiments of the present application, the safety range of the battery pack refers to the voltage, current and other parameter ranges that the battery pack can maintain in a safe state during the charging and discharging process; the quadratic programming algorithm is a mathematical optimization algorithm for solving the optimal solution of a quadratic objective function under convex constraint conditions; and the optimal power distribution instruction set refers to the power distribution scheme of the generator set and the battery pack that makes the superimposed fuel consumption rate optimal, which is obtained by solving by the quadratic programming algorithm.

[0071] In the embodiment of the present application, the market price of the current marine fuel oil is obtained, including: accessing the information management system of the ship or connecting the external market price database to obtain the market price of the current marine fuel oil in real time, for example, the obtained market price is 5 yuan / kg.

[0072] In the embodiment of the present application, the consumable fuel oil mass corresponding to a unit of currency is calculated according to the measured low heat value of the generator set and the market price, including: the measured low heat value of the generator set is measured in advance by professional equipment, for example, the measured low heat value is 42000 kJ / kg. The calculation method of the consumable fuel oil mass corresponding to a unit of currency is 1 divided by the market price, that is, the fuel oil mass that can be purchased by 1 yuan. If the market price is 5 yuan / kg, the consumable fuel oil mass corresponding to a unit of currency is 1 / 5=0.2 kg / yuan.

[0073] In the embodiment of the present application, the equivalent fuel consumption is generated by dividing the unilateral loss compensation value by the consumable fuel oil mass corresponding to a unit of currency, including: the unilateral loss compensation value obtained in S5 is obtained, for example, the unilateral loss compensation value is 40 yuan. Divide the compensation value by the consumable fuel oil mass corresponding to a unit of currency, that is, 40 yuan divided by 0.2 kg / yuan, to obtain the equivalent fuel consumption of 20 kg.

[0074] In the embodiment of the present application, an optimization model is established with the superimposed fuel consumption rate as the objective function, including: the superimposed fuel consumption rate is the sum of the original fuel consumption rate obtained in S1 and the rate converted according to the unit time of the equivalent fuel consumption, for example, the original fuel consumption rate is 36 kg / h, and the equivalent fuel consumption is 20 kg (calculated according to 1 hour), then the superimposed fuel consumption rate is 56 kg / h. Take this superimposed rate as the objective function, the goal is to make the function value minimum.

[0075] In the embodiment of the present application, the power limit of the generator set and the safety range of the battery pack are added as constraint conditions, including: the power limit of the generator set is determined according to its design parameters and operation experience, for example, the power limit is 50-200 kW. The safety range of the battery pack is determined according to the specification book of the battery pack, for example, the voltage safety range is 200-250 V, and the current safety range is -150 to 150 A. These parameter ranges are added as constraint conditions to the optimization model to ensure that the power distribution scheme solved is within the safety range.

[0076] In the embodiment of the present application, the optimal power distribution instruction set of the generator set and the battery pack is solved by a quadratic programming algorithm, including: inputting the established optimization model with the superimposed fuel consumption rate as the objective function and the generator set power limit and the battery pack safety range as the constraint condition into the quadratic programming algorithm. The algorithm solves the model to obtain the power distribution values of the generator set and the battery pack that optimize the objective function, for example, the generator set bears 120 kilowatts of power and the battery pack bears 80 kilowatts of power, and these distribution values form the optimal power distribution instruction set.

[0077] In the embodiment of the present application, this step takes the implicit loss cost of the battery into account for fuel consumption, making the ship power distribution more economical and reasonable, and solving the problem of poor overall economy caused by the traditional method of only focusing on instantaneous fuel consumption and ignoring battery aging cost.

[0078] As shown in Figure 3 is a functional module diagram of a fuel optimization calculation system for ship energy management provided by an embodiment of the present application.

[0079] The fuel optimization calculation system for ship energy management 100 can be installed in an electronic device. According to the functions implemented, the fuel optimization calculation system for ship energy management 100 can include a data acquisition module 101, a battery loss quantification module 102, a high loss state determination module 103, a loss difference calculation module 104, a single-sided loss compensation module 105, and a power distribution optimization module 106. The modules of the present application can also be referred to as units, which refer to a series of computer program segments that can be executed by an electronic device processor and can complete a fixed function, which are stored in the memory of the electronic device.

[0080] In the embodiment, the functions of each module / unit are as follows: The data acquisition module 101 is used to acquire the fuel consumption rate of the generator set, the charge and discharge current of the battery pack, and the environmental temperature in real time. The battery loss quantification module 102 is used to determine the instantaneous charge and discharge rate factor of the battery pack according to the charge and discharge current, query the temperature-rate decay mapping table of the battery pack to output a basic decay coefficient based on the instantaneous charge and discharge rate factor and the environmental temperature, and generate an actual loss rate by associating the basic decay coefficient with the cycle life model of the battery pack. The high loss state determination module 103 is used to mark the current battery pack as being in a high loss state when the actual loss rate exceeds a preset loss rate threshold. The loss difference calculation module 104 is used to calculate the positive difference between the actual loss rate and the preset loss rate threshold in real time for the battery pack in the high loss state. The single-side loss compensation module 105 is configured to map the positive difference into an accelerated aging life attenuation increment based on a current-temperature-life attenuation three-dimensional relationship in a battery aging characteristic curve, and multiply the accelerated aging life attenuation increment by a replacement cost coefficient of the battery pack to generate a single-side loss compensation value; The power distribution optimization module 106 is configured to convert the single-side loss compensation value into an equivalent fuel loss amount, and add the equivalent fuel loss amount to the fuel consumption rate to generate a ship power distribution optimization instruction based on the added fuel consumption rate.

[0081] In several embodiments provided by the present application, it should be understood that the disclosed method and system can be implemented in other manners. For example, the described system embodiment is merely illustrative. For example, the division of the modules is merely logical function division. In actual implementation, another division manner can be used.

[0082] The modules illustrated as separated components can or can not be physically separated, and the components illustrated as modules can or can not be physical units, that is, can be located in one place, or can be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment.

[0083] In addition, each function module in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of hardware plus software function modules.

[0084] It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

[0085] The embodiments of the present application can acquire and process related data based on artificial intelligence technology. Artificial intelligence is a theory, method, technology and application system for simulating, extending and expanding human intelligence by using a digital computer or a machine controlled by a digital computer, perceiving an environment, acquiring knowledge and using the knowledge to obtain optimal results.

[0086] Finally, it should be noted that the above embodiments are merely used to illustrate the technical solutions of the present application but not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A fuel optimization calculation method for ship energy management, characterized in that: The method comprises: Real-time collection of fuel consumption rate of generator sets, charge and discharge current of battery packs, and ambient temperature; determining an instantaneous charge and discharge rate factor of the battery pack according to the charge and discharge current, querying a temperature-rate attenuation mapping table of the battery pack based on the instantaneous charge and discharge rate factor and the ambient temperature to output a basic attenuation coefficient, and associating the basic attenuation coefficient with a cycle life model of the battery pack to generate an actual loss rate; When the actual loss rate exceeds a preset loss rate threshold, marking the current battery pack as being in a high loss state; For a battery pack in a high loss state, calculating in real time the positive difference between the actual loss rate and the preset loss rate threshold; Mapping the positive difference into an accelerated aging life attenuation increment based on the current-temperature-life attenuation three-dimensional relationship in the battery aging characteristic curve, and multiplying it by the replacement cost coefficient of the battery pack to generate a unilateral loss compensation value; The unilateral loss compensation value is converted into an equivalent fuel loss amount and added to the fuel consumption rate, and a ship power distribution optimization instruction is generated based on the superimposed fuel consumption rate.

2. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The real-time collection of the fuel consumption rate of the generator set, the charge and discharge current of the battery pack, and the ambient temperature includes: Obtain the real-time fuel flow signal of the diesel generator set through the ship bus interface to generate the fuel consumption rate; Collect the charge and discharge current of the lithium-ion battery pack through the battery management system; The temperature sensor array is used to obtain temperature readings at distributed points in the battery compartment, and the highest reading is taken as the ambient temperature.

3. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The determining of the instantaneous charge and discharge rate factor of the battery pack according to the charge and discharge current includes: The rated capacity value of the battery pack is obtained, the absolute value of the charge and discharge current is divided by the rated capacity value, and an instantaneous charge and discharge rate factor of the battery pack is output.

4. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The step of querying the temperature-rate attenuation mapping table of the battery pack based on the instantaneous charge and discharge rate factor and the ambient temperature to output a basic attenuation coefficient includes: Calling a two-dimensional lookup table stored in a battery management system, wherein the horizontal axis of the two-dimensional lookup table is the rate factor and the vertical axis is the ambient temperature; The instantaneous charge and discharge rate factor and ambient temperature under the current working conditions are used as the joint index coordinates to output a basic attenuation coefficient between 0 and 1.

5. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The generating of an actual loss rate by associating the basic attenuation coefficient with a cycle life model of the battery pack includes: The basic decay coefficient is input into the exponential life decay function constructed based on the Arrhenius equation; The exponential life decay function is cumulatively corrected in combination with the number of cycles of the battery pack, and an actual loss rate representing the speed at which the battery life is consumed is output.

6. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: When the actual loss rate exceeds a preset loss rate threshold, marking the current battery pack as being in a high loss state includes: Determining an upper limit of the loss rate of the battery pack under normal operating conditions based on statistics of a historical ship operation database; Combined with the critical conditions for accelerated aging in the battery specification, verify the rationality of the loss rate upper limit, and solidify the verified loss rate upper limit as the preset loss rate threshold; The actual loss rate is continuously compared with the preset loss rate threshold, and when the actual loss rate is continuously greater than the preset loss rate threshold for a preset time period, a high loss state of the current battery pack is marked.

7. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The method of mapping the positive difference into an accelerated aging life attenuation increment based on the current-temperature-life attenuation three-dimensional relationship in the battery aging characteristic curve and multiplying the value by the replacement cost coefficient of the battery pack to generate a unilateral loss compensation value includes: Conduct multi-condition cycle aging tests on the same battery pack in a laboratory environment, and record the life attenuation data under different charge and discharge current-ambient temperature combinations; Based on the life decay data, a nonlinear decay surface with current-temperature dual dimensions is generated in combination with the least squares method, wherein the nonlinear decay surface has the charge and discharge current under the current working condition as the X-axis coordinate and the ambient temperature as the Y-axis coordinate; Extracting the accelerated aging life attenuation increment corresponding to the positive difference in the nonlinear attenuation surface; Converting the accelerated aging life attenuation increment into a capacity attenuation percentage and multiplying the percentage by the total capacity of the battery pack to obtain an equivalent loss capacity; The equivalent loss capacity is multiplied by the unit capacity replacement cost of the battery pack, and an economic compensation value is output as a unilateral loss compensation value.

8. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: Converting the unilateral loss compensation value into an equivalent fuel loss amount includes: Get the current market price of marine fuel oil; Calculating the mass of consumable fuel corresponding to a unit of currency based on the measured lower calorific value of the generator set and the market price; The unilateral loss compensation value is divided by the consumable fuel mass corresponding to the unit currency to generate an equivalent fuel loss amount for cost optimization.

9. The fuel optimization calculation method for ship energy management according to claim 1, characterized in that: The generating of the ship power distribution optimization instruction based on the superimposed fuel consumption rate includes: Establish an optimization model with the superimposed fuel consumption rate as the objective function; Adding the power limit of the generator set and the safety range of the battery pack as constraints; The optimal power allocation instruction set of the generator set and the battery set is solved by a quadratic programming algorithm.

10. A fuel optimization calculation system for ship energy management, characterized in that: The system comprises: Data acquisition module, used to collect real-time information on the fuel consumption rate of the generator set, the charge and discharge current of the battery pack, and the ambient temperature; a battery loss quantification module, configured to determine an instantaneous charge and discharge rate factor of the battery pack based on the charge and discharge current, query a temperature-rate attenuation mapping table of the battery pack based on the instantaneous charge and discharge rate factor and the ambient temperature to output a basic attenuation coefficient, and associate the basic attenuation coefficient with a cycle life model of the battery pack to generate an actual loss rate; a high-loss state determination module, configured to mark the current battery pack as being in a high-loss state when the actual loss rate exceeds a preset loss rate threshold; A loss difference calculation module is used to calculate the positive difference between the actual loss rate and the preset loss rate threshold in real time for the battery pack in a high loss state; a unilateral loss compensation module, configured to map the positive difference into an accelerated aging life attenuation increment based on the current-temperature-life attenuation three-dimensional relationship in the battery aging characteristic curve, and multiply the result by the replacement cost coefficient of the battery pack to generate a unilateral loss compensation value; The power distribution optimization module is used to convert the unilateral loss compensation value into an equivalent fuel loss amount and add it to the fuel consumption rate, and generate a ship power distribution optimization instruction based on the superimposed fuel consumption rate.

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