Method for calculating optimal configuration scheme of generator based on ship power load

Abstract

This invention provides a method for calculating the optimal generator configuration scheme based on ship electrical load. The specific steps include: determining the power requirements of each functional module under different operating conditions, and determining the total power required for each operating condition. Functional modules include: electric propulsion equipment, dual-fuel supply system, engine room auxiliary machinery, air conditioning, refrigeration and mechanical ventilation, deck machinery, maintenance equipment, galley and laundry equipment, electrical equipment, and mechanical ventilation when refrigerated containers are installed in the cargo hold. Operating conditions include: navigation, departure without side propulsion, departure with side propulsion, loading and unloading, and berthing. Generator configuration schemes are generated based on at least the total power and configuration information for all ship operating conditions. Configuration information includes: the total number of generators and the load rate requirements and / or the number of standby generators for the corresponding operating conditions. All generator configuration schemes are pre-screened for maximum load conditions and load rate limits. Cost screening is performed on the screened schemes to output the target generator configuration scheme.

Description

Technical Field

[0001] This invention relates to the field of power distribution in marine electrical systems, and in particular to a method for calculating the optimal generator configuration based on the ship's electrical load. Background Technology

[0002] The ship's electrical system consists of dozens of subsystems, including the bow thruster system, intercom system, and steering gear system. Under different navigation conditions, the operating states of each system vary, resulting in complex variations in the ship's electrical load. Therefore, when configuring generators, it is necessary to comprehensively consider the load characteristics under various typical operating conditions and rationally determine the generator set capacity configuration, operating combinations, and switching strategies to ensure power supply reliability and optimize operational efficiency.

[0003] Currently, there are many generator models available on the market. Their rated power, number of cylinders, and procurement costs all have a significant impact on the decision-making process. These factors are mutually restrictive, making it difficult for manual evaluation to fully consider all technical and economic indicators.

[0004] CN113659567B discloses a design method and apparatus for an FPSO power system. The design method includes the following steps: for each power load in the FPSO, different power weights are set according to the usage of the power load under different operating conditions; the power load of the FPSO under different operating conditions is calculated based on the power of each power load and the power weight of each power load under different operating conditions; the target generator is selected based on the power load of the FPSO under different operating conditions and the parameters of the alternative generators, thus realizing a reasonable design of the FPSO power system. This patent, after determining the generator configuration, calculates how to activate the generator based on the load of the FPSO power system, but it does not address how to configure the generator at the initial design stage, comprehensively considering factors such as the manufacturer, model, and price of different generators, and comprehensively considering the generator start-up and shutdown schemes and load factors under all operating conditions.

[0005] Currently, the configuration of ship generators mainly relies on manual experience and basic Excel formulas for calculation. This traditional method has significant limitations: First, it depends excessively on the personal experience of senior engineers, lacking a systematic and standardized decision-making basis; second, the manual calculation process is inefficient and cannot quickly respond to changing operating conditions; more importantly, existing methods cannot achieve quantitative evaluation of key parameters, resulting in a lack of objectivity in configuration schemes. Given that generator selection directly affects the stability, economy, and safety of the ship's electrical system, this manual design mode has become a key bottleneck restricting the improvement of ship electrical design standards. Summary of the Invention

[0006] In view of the shortcomings of the above-mentioned related technologies, the purpose of this invention is to provide a method for calculating the optimal configuration scheme of generators based on ship electrical load, so as to solve the problems of lack of standard and low efficiency in the manual design mode of related technologies.

[0007] To achieve the above and other related objectives, this invention provides a method for calculating the optimal generator configuration based on ship electrical load, the specific steps of which include:

[0008] Determine the power requirements of each functional module under different operating conditions, and determine the total power required for each operating condition based on the power requirements. The functional modules include: electric propulsion equipment, dual fuel supply system, engine room auxiliary machinery, air conditioning, refrigeration and mechanical ventilation, deck machinery, machine repair equipment, galley and laundry equipment, electrical equipment, and mechanical ventilation when cold boxes are installed in the cargo hold. The operating conditions include: navigation condition, departure condition without side propulsion, departure condition with side propulsion, loading and unloading condition, and berthing condition.

[0009] A generator configuration scheme is generated based on the total power and configuration information under all operating conditions of the ship. The configuration information includes: the total number of generators and the target operating condition attribute information, which includes: the load rate requirement and / or the number of standby generators for the corresponding operating condition.

[0010] All generator configuration schemes are pre-screened for maximum load conditions and load rate limits.

[0011] Cost screening is performed on the solutions selected in the first two rounds to output the target generator configuration scheme.

[0012] Optionally, a power transfer model is established based on the equipment power parameters to obtain the grid input power. The power transfer model is: P 电网 =P 马达 / η×K, where P 电网 P is the power input to the power grid. 马达 η is the rated power of the motor. 马达 Where K is the motor efficiency and K is the load factor.

[0013] Optionally, the step of generating generator configuration schemes based on the total power under all operating conditions of the ship is as follows: first, determine all possible combinations of generators, and then check each scheme to select the scheme that meets the requirements of all operating conditions.

[0014] Optionally, the steps for determining all combinations of generators are as follows: first, determine the types of generators, then recursively determine the number of each type of generator to be used. If the current total number of all types of generators is equal to the target number, and the number of all types of generators has been determined, then the combination is a complete scheme. If the current total number is less than the target number, and there are still remaining generator types to be processed, then continue to determine the next type of generator. If the current total number has exceeded the target number, then stop immediately and reconfigure a new scheme.

[0015] Optionally, the step of checking each scheme to select the scheme that meets all operating conditions is as follows: calculate all operating states under the configuration and the total generator power of each operating state; calculate whether the configuration can provide at least one operating state that meets the requirements under each operating condition, and exclude it if not; if the configuration can provide at least one operating state that meets the requirements under all operating conditions, it is marked as a feasible scheme, and the operating state that meets the requirements and the load rate under each operating condition are recorded.

[0016] Optionally, after all the schemes are generated, they are input into the Python program in Excel format for processing. The processing includes parameter calculation, logic verification, and result output.

[0017] Optionally, the pre-screening step for the maximum load condition is as follows: analyze and determine the maximum load condition of the ship, and screen out suitable schemes based on the characteristics of the condition.

[0018] Optionally, the load rate limit screening step is as follows: first calculate the total load for each operating condition except for the maximum load condition, and then allocate the generator start-stop in each scheme so that the load rate of each scheme under each operating condition can be within the ideal range. If the scheme cannot meet the load rate under a certain operating condition, then the scheme is excluded.

[0019] As described above, the method for calculating the optimal generator configuration based on ship electrical load of the present invention has the following beneficial effects: by integrating traditional configuration experience with modern programming technology, it overcomes the three major limitations of manual decision-making: strong reliance on experience, low computational efficiency, and insufficient quantification. Furthermore, the present invention achieves intelligent analysis of load conditions, multi-parameter quantitative evaluation, and automatic generation of configuration schemes, possessing advantages such as accurate calculation, efficient decision-making, and quantifiable results. Attached Figure Description

[0020] Figure 1 The diagram shows a flowchart illustrating the method for optimizing generator configuration in an embodiment of the present invention. Detailed Implementation

[0021] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0022] In the detailed description of embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged and not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0023] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for the device in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or there may be one or more layers in between. The phrase “between” as used herein includes both endpoint values.

[0024] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0025] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0026] like Figure 1 As shown in the figure, this embodiment provides a method for calculating the optimal generator configuration scheme based on the ship's electrical load. The specific steps are as follows:

[0027] The total power of the activated equipment under all operating conditions on the ship is obtained based on the equipment and power parameters of each piece of equipment.

[0028] Based on the operating characteristics of the ship's electrical system, the embodiments of this application divide its load into the following functional modules: electric propulsion equipment, dual fuel supply system, engine room auxiliary machinery, air conditioning, refrigeration and mechanical ventilation, deck machinery, machine repair equipment, galley and laundry equipment, electrical equipment, and mechanical ventilation when cold boxes are installed in the cargo hold.

[0029] This modular partitioning method fully considers the functional independence, operating characteristics, and load features of each system, providing a clear load analysis framework for subsequent generator configuration optimization. Specifically, it ensures that each module has clear functional boundaries, that the loads within the same module have similar power consumption characteristics, and that they meet the actual operational and management needs of the ship.

[0030] Different devices have different power ratings. The power input to the power grid can be calculated by establishing a power transfer model for the ship's electrical load. The power transfer model is as follows:

[0031] P 电网 =P 马达 / η×K

[0032] Among them, P 电网 P is the power input to the grid (kW). 马达 η is the rated power of the motor (kW). 马达 The motor efficiency is 0.85-0.95, and K is the load factor (1.05-1.20). The motor efficiency and load factor are usually derived from the manufacturer's equipment parameters, and the specifications also have certain requirements for their range.

[0033] The embodiments of this application divide the operating conditions into: navigation operating condition, departure operating condition without side propulsion, departure operating condition with side propulsion, loading and unloading operating condition, and berthing operating condition. The inventors of this application discovered in their research that the power activation of each load module differs under different operating conditions.

[0034] For example, the electric propulsion equipment module is only put into operation when the side propulsion is used for departure; while other load modules (such as the engine room auxiliary machinery system) exhibit more complex power distribution characteristics depending on the operating conditions.

[0035] The embodiments of this application determine the functional modules that are activated under different operating conditions and sum the power of the activated devices to obtain the total power of the ship under each operating condition (characterized by Table 1 below). Based on the total power of the ship, a generator can be selected. Table 1 is used to provide the power requirements of each functional module under different operating conditions.

[0036] Table 1 Operating Condition Activation Table

[0037] Load module Navigation conditions Without side-launch port Side-launched port Loading and unloading conditions Parking conditions Electric propulsion equipment 0 0 12000 0 0 Dual-fuel supply system 800 800 800 800 200 Auxiliary machinery 3000 3200 3200 2800 1500 Air conditioning, refrigeration and mechanical ventilation 2000 2200 2200 2500 1200 Deck machinery 500 1500 1500 3000 200 Machine repair equipment 100 100 100 100 50 Kitchen laundry equipment 300 300 300 300 100 electrical equipment 400 400 400 400 200 Mechanical ventilation when refrigerated containers are installed in the cargo hold 0 0 800 0 0 Total power requirement (kW) 7000 8500 21300 9900 3450

[0038] Based on the generator configuration scheme for generating total power under various operating conditions of the entire ship.

[0039] Specifically, generating all generator procurement combinations involves the following steps: First, determine the types of generators that can be procured. Then, based on the total number of generators input (i.e., the target number of units), recursively determine the usage quantity of each type of generator. If the current total number of generators equals the target number, and the quantity of all types of generators has been determined, then this combination constitutes a complete solution, and the result is saved. If the current total number of generators is less than the target number, and there are still remaining generator types to process, then continue determining the next type of generator. If the current total number of generators has exceeded the target number, then immediately stop and reconfigure a new solution. Repeat the above operations until all generator combinations are completed. The usage quantity of each type of generator ranges from 0 to n, where n is the total number of generators required for the entire ship.

[0040] For example, there are 3 types of generators (A, B, C), and 4 units need to be purchased (the ship requires 4 generators).

[0041] First, determine the number of generators A. The situations for generators A are as follows: Buy 0 generators A: 4 generators will be allocated to B and C; Buy 1 generator A: 3 generators will be allocated to B and C; Buy 2 generators A: 2 generators will be allocated to B and C; Buy 3 generators A: 1 generator will be allocated to B and C; Buy 4 generators A: 0 generators will be allocated to B and C.

[0042] Then, based on the situation of generator A, determine the number of generator B. If 1 A is purchased, the situations of generator B are as follows: if 0 B are purchased, the remaining 3 will be given to C; if 1 B is purchased, the remaining 2 will be given to C; if 2 B are purchased, the remaining 1 will be given to C; if 3 B are purchased, the remaining 0 will be given to C.

[0043] Then, based on the situation of generator B, determine the number of generator C. If 2 generators of B are purchased, then 1 generator of C is needed. At this time, 1 generator of A + 2 generators of B + 1 generator of C constitute a complete solution.

[0044] After obtaining all solutions, each solution is checked to determine if it meets the requirements under all operating conditions. For each operating condition, all generator start-stop combinations are tried. For example, a solution with 3 generators has 8 operating states (from all off to all on). The specific steps are: calculate all operating states under this configuration and the total generator power in each operating state; calculate whether the configuration can provide at least one compliant operating state under each operating condition, and exclude it if not; if the configuration can provide at least one compliant operating state under all operating conditions, it is marked as a feasible solution, and the compliant operating state and load rate are recorded for each operating condition. It should be noted that for the same configuration under the same operating condition, meeting the load rate requirement with different operating states is considered as two different solutions.

[0045] Filter all options and output the optimal option.

[0046] Specifically, all data for the combined schemes can be input into the Python environment for processing, either in Excel format or manually. When inputting data in Excel format, generator data is entered into the Python processing environment using a standardized template. On the Python side, the pandas data processing framework is used to batch process the imported data, including but not limited to core processing flows such as parameter calculation, logical verification, and result output. The Python-Excel collaborative processing solution is mainly used to input the activation status of different devices under various operating conditions, the power parameters of each device, the power of different generators, and their purchase prices.

[0047] When the data volume is small and requires adjustments and debugging, manual data entry is used. Basic command-line input can be achieved using Python's `input()` function, and a GUI framework is integrated to create a visual parameter input panel. Engineers can then edit the parameters visually through the configuration interface. The system includes a built-in try-except exception handling mechanism and parameter range validation to ensure the validity of the input data. Furthermore, all manually entered parameters are automatically stored in a temporary variable space for easy real-time modification and debugging later.

[0048] The screening of all options includes pre-screening under maximum load conditions, load factor limitation screening, and cost screening. When using maximum load conditions for initial screening, the maximum load condition of the ship is determined through engineering analysis (taking a container ship as an example, typically the operating state with side propellers departing the port and all refrigerated containers fully open). This condition has the following characteristics: all generators, except for the shaft-driven generator, are operating simultaneously; only core parameters such as the total number of generators, power configuration, and load factor need to be considered. Taking a certain type of large container ship project as an example, according to the specifications, it requires: 5 main generators; the load factor requirement under maximum load conditions is within 95%-100%. Based on the above parameters, the system first automatically enumerates all generator combination options and performs initial screening based on the above screening conditions.

[0049] In some embodiments of this application, the scheme for determining the maximum load condition includes: Example 1: based on engineering experience and preset rules in the specifications.

[0050] The system can pre-configure a set of rules based on ship type and common design specifications. Example of a rule base:

[0051] For container ships: the rule is directly defined as "maximum load condition = 'departure condition with side propulsion'". This is because the engineering consensus is that at this time, both propulsion power and refrigerated container (cold box) load reach their peak simultaneously.

[0052] For tankers / bulk carriers: the rule may be defined as "maximum load condition = 'loading and unloading condition'", because a large number of cargo pumps or unloaders are running at the same time.

[0053] For passenger ro-ro ships: the rule may be defined as "maximum load condition = 'port entry and exit condition (with side thrust)'", taking into account propulsion, hotel load and terminal operations.

[0054] Implementation process: When initializing the system, the user first selects the "ship type" (e.g., container ship). The system then automatically assigns the corresponding operating condition as the maximum load condition based on built-in rules and uses it as the focus of subsequent calculations.

[0055] Example 2: Automatic identification based on computational data.

[0056] After the user has fully entered the power parameters and operating condition activation table for all devices, the system can perform a quick pre-calculation to assist in the judgment.

[0057] Implementation process:

[0058] 1. The system temporarily calculates the total power demand for each operating condition (P_sailing, P_departure, etc.) based on the input data.

[0059] 2. Compare the calculated total power for all operating conditions and mark the operating condition with the largest value as the "calculated maximum load operating condition".

[0060] 3. The system can recommend this result to the user, who can then make the final confirmation or modification.

[0061] Advantages: More objective and data-driven, especially suitable for non-standard ship types or special configurations.

[0062] By employing a pre-screening method based on maximum load conditions, the number of schemes requiring further processing can be effectively reduced. Practical engineering applications demonstrate that this method reduces computational load, significantly improves scheme optimization efficiency, and ensures the engineering feasibility of the screened results. This phased processing strategy considers both computational efficiency and ensures the power supply reliability requirements of critical operating conditions.

[0063] Next, the pre-screened schemes are subjected to load rate limitation screening. At this stage, the following should be considered: during navigation operation, at least one generator must be available as a backup; during non-navigation operation, shaft-driven generators must not be used (if the main engine speed is insufficient). The system will automatically identify the configuration characteristics of each scheme under different operating conditions and forcibly exclude schemes that violate any of the above conditions. For schemes that do not violate the above conditions, the system first calculates the total load for each operating condition except for the maximum load condition, and then allocates the generator start / stop for each scheme to ensure that the load rate of each scheme under each operating condition is within the ideal range. If a scheme cannot meet the load rate requirement for a certain operating condition, then that scheme is excluded.

[0064] After the first two rounds of screening, the system has automatically generated all feasible solutions. The system will automatically calculate the total purchase cost of each solution and perform a comprehensive ranking using a multi-dimensional evaluation algorithm. Finally, it will output 3-5 of the most cost-effective optimal solutions, including a detailed configuration list and cost analysis.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for calculating the optimal generator configuration scheme based on ship electrical load, characterized in that, The specific steps include: Determine the power requirements of each functional module under different operating conditions, and determine the total power required for each operating condition based on the power requirements. The functional modules include: electric propulsion equipment, dual fuel supply system, engine room auxiliary machinery, air conditioning, refrigeration and mechanical ventilation, deck machinery, machine repair equipment, galley and laundry equipment, electrical equipment, and mechanical ventilation when cold boxes are installed in the cargo hold. The operating conditions include: navigation condition, departure condition without side propulsion, departure condition with side propulsion, loading and unloading condition, and berthing condition. A generator configuration scheme is generated based on the total power and configuration information under all operating conditions of the ship. The configuration information includes: the total number of generators and the target operating condition attribute information, which includes: the load rate requirement and / or the number of standby generators for the corresponding operating condition. All generator configuration schemes are pre-screened for maximum load conditions and load rate limits. Cost screening is performed on the solutions selected in the first two rounds to output the target generator configuration scheme.

2. The method for calculating the optimal generator configuration scheme based on ship electrical load according to claim 1, characterized in that: A power transfer model is established based on the equipment power parameters to obtain the grid input power. The power transfer model is: P 电网 =P 马达 / η×K, where P 电网 P is the power input to the power grid. 马达 η is the rated power of the motor. 马达 Where K is the motor efficiency and K is the load factor.

3. The method for calculating the optimal generator configuration scheme based on ship electrical load according to claim 1, characterized in that: The steps for generating generator configuration schemes based on the total power of the entire ship under various operating conditions are as follows: first, determine all possible combinations of generators, and then check each scheme to select the scheme that meets the requirements of all operating conditions.

4. The method for calculating the optimal generator configuration based on ship electrical load according to claim 5, characterized in that: The steps for determining all possible combinations of generators are as follows: First, determine the types of generators, then recursively determine the number of each type of generator to be used. If the total number of all types of generators is equal to the target number, and the number of all types of generators has been determined, then the combination is a complete scheme. If the total number of generators is less than the target number, and there are still remaining generator types to be processed, then continue to determine the next type of generator. If the total number of generators has exceeded the target number, then stop immediately and reconfigure a new scheme.

5. The method for calculating the optimal generator configuration scheme based on ship electrical load according to claim 5, characterized in that: The steps for checking each scheme to select the scheme that meets all operating conditions are as follows: calculate all operating states under the configuration and the total generator power of each operating state; calculate whether the configuration can provide at least one operating state that meets the requirements under each operating condition, and exclude it if it cannot; if the configuration can provide at least one operating state that meets the requirements under all operating conditions, it is marked as a feasible scheme, and the operating state that meets the requirements and the load rate under each operating condition are recorded.

6. The method for calculating the optimal generator configuration scheme based on ship electrical load according to claim 1, characterized in that: After all the solutions are generated, they are input into the Python program in Excel format for processing. The processing includes parameter calculation, logic verification, and result output.

7. The method for calculating the optimal generator configuration based on ship electrical load according to claim 1, characterized in that: The pre-screening steps for the maximum load condition are as follows: analyze and determine the maximum load condition of the ship, and screen out the schemes that meet the conditions based on the characteristics of the condition.

8. The method for calculating the optimal generator configuration scheme based on ship electrical load according to claim 1, characterized in that: The load rate limit screening steps are as follows: first, calculate the total load for each operating condition except for the maximum load condition, and then allocate the generator start-stop in each scheme so that the load rate of each scheme under each operating condition can be within the ideal range. If the scheme cannot meet the load rate under a certain operating condition, then the scheme is excluded.

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