CN-116238695-B - Energy management method and storage medium for electric aircraft composite energy system

CN116238695BCN 116238695 BCN116238695 BCN 116238695BCN-116238695-B

Abstract

The invention relates to an energy management method and a storage medium of an electric aircraft composite energy system, wherein the method comprises the steps of drawing a power demand-time curve according to a flight plan before an electric aircraft takes off; according to the output characteristics of each unit of the electric aircraft composite energy system, an energy optimization scheduling model which aims at minimizing energy consumption cost is built, technical parameters of each unit of the electric aircraft and a power demand-time curve are input, model solving is carried out, an energy scheduling plan of the composite energy system is obtained, in the real-time flight process of the electric aircraft, the deviation between the real-time power demand of the electric aircraft and the energy scheduling plan of the composite energy system is the minimum as an optimization target, a system energy real-time control model is built, and an actual energy management strategy of the composite energy system is obtained. Compared with the prior art, the method provided by the invention has the advantages of high energy utilization efficiency, good economy, high feasibility and the like through the scheduling optimization before flight and the real-time operation optimization during flight.

Inventors

HE YIJUN
DONG XIAOJIAN
SHEN JIANI

Assignees

上海交通大学

Dates

Publication Date: 20260508
Application Date: 20221129

Claims (10)

1. An energy management method of an electric aircraft composite energy system, comprising the steps of: s1, before the electric aircraft takes off, drawing a power demand-time curve of the electric aircraft according to a flight plan of the electric aircraft; S2, constructing an energy optimization scheduling model which takes the energy cost of the composite energy system as an optimization target according to the output characteristics and the operation constraint conditions of each unit of the composite energy system of the electric aircraft; s3, inputting technical parameters of each unit of the electric aircraft and a power demand-time curve into the energy optimization scheduling model, and carrying out model solving to obtain an energy scheduling plan of the composite energy system; and S4, calculating the deviation between the real-time power demand of the electric aircraft and the energy scheduling plan of the composite energy system by taking the energy scheduling plan of the composite energy system as a base line in the real-time flight process of the electric aircraft, and constructing a system energy real-time control model by taking the minimum deviation as an optimization target to obtain an actual energy management strategy of the composite energy system.
2. The energy management method of an electric aircraft composite energy system of claim 1, wherein the electric aircraft power demand-time profile comprises electric aircraft power demand-time profiles during take-off, climb, cruise, and descent phases.
3. The energy management method of an electric aircraft composite energy system of claim 2, wherein the composite energy system comprises a hydrogen fuel cell, a lithium ion battery, and a supercapacitor; during the take-off stage and the climbing stage, the hydrogen fuel cell, the lithium ion battery and the super capacitor are powered together; during the cruise phase and the descent phase, power is supplied by a hydrogen fuel cell and a lithium ion battery.
4. The energy management method of an electric aircraft composite energy system according to claim 1, wherein the optimization objective of the energy optimization scheduling model is: in the formula, The total energy cost of the electric aircraft composite energy system; And Respectively the residual electric energy of the lithium ion battery and the super capacitor after the flying is finished, And The residual electric energy of the lithium ion battery and the supercapacitor before the flight starts; And The price of charging and hydrogen charging respectively, The output power of the fuel cell system at time t, In order to be an electro-hydrogen conversion coefficient, Time intervals are scheduled for energy management.
5. The energy management method of an electric aircraft composite energy system of claim 1, wherein the operating constraints include busbar power balance constraints, energy storage device energy balance constraints, system unit power constraints, and system unit energy constraints; The expression of the bus power balance constraint is as follows: in the formula, 、、 And The charging efficiency, the discharging efficiency and the charging power and the discharging power of the lithium ion battery at the moment t are respectively; 、、 And The charging efficiency, the discharging efficiency and the charging power and the discharging power of the super capacitor at the moment t are respectively; And The output power of the fuel cell system at the time t and the power requirement of the electric aircraft at the time t are respectively; And Conversion efficiency of the DC-DC bidirectional converter and the high-speed motor respectively; the energy balance constraint expression of the energy storage device is as follows: in the formula, 、 And The residual electric energy of the lithium ion battery at the initial moment, the t-1 moment and the t moment respectively; 、 And The residual electric energy of the super capacitor at the initial moment, the t-1 moment and the t moment respectively; Scheduling a time interval for energy management; The expression of the power constraint of each unit of the system is as follows: in the formula, And Maximum allowable charge and discharge multiplying power of lithium ion battery respectively; And Maximum allowable charge and discharge multiplying power of the super capacitor respectively; And 0-1 Variables representing whether the lithium ion battery is charged and discharged, respectively; And 0-1 Variables showing whether the supercapacitor is charged and discharged, respectively; And Maximum allowable up/down hill climbing rates of the fuel cell, respectively; 、 And The design capacities of the lithium ion battery, the super capacitor and the fuel cell are respectively; The output power of the fuel cell at the time t-1; the energy constraint expression of each unit of the system is as follows: in the formula, Designing a hydrogen storage amount for the hydrogen storage system; the conversion coefficient of electric hydrogen is the conversion coefficient of hydrogen and the generated energy of the fuel cell.
6. The energy management method of the electric aircraft composite energy system according to claim 1, wherein the technical parameters of each unit of the electric aircraft comprise design capacity, maximum allowable charge/discharge multiplying power and charge/discharge efficiency of a lithium ion battery, design capacity, maximum allowable charge/discharge multiplying power and charge/discharge efficiency of a super capacitor, design capacity and maximum allowable ascending/descending slope rate of a fuel battery, design hydrogen storage amount and electric hydrogen conversion coefficient of a hydrogen storage system, energy conversion efficiency of a DC-DC bidirectional inverter and a high-speed motor, and charging and hydrogen charging price.
7. The method of claim 1, wherein the composite energy system energy schedule comprises a time-of-day power output profile of a fuel cell, a lithium ion battery, and a supercapacitor.
8. The energy management method of an electric aircraft composite energy system according to claim 1, wherein the expression of the optimization objective of the system energy real-time control model is: in the formula, The deviation between the actual power output of the composite energy system at the moment t and the plan is obtained; And The actual residual electric energy of the lithium ion battery and the supercapacitor at the moment t respectively; The actual output power of the fuel cell at the time t; the residual electric energy of the lithium ion battery at the moment t; the residual electric energy of the super capacitor at the moment t; the output power of the fuel cell system at the time t; 、 And Penalty factors for power output variation of lithium ion batteries, supercapacitors and fuel cells respectively, Time intervals are scheduled for energy management.
9. The energy management method of an electric aircraft composite energy system according to claim 8, wherein the constraint conditions satisfied by the system energy real-time control model are: in the formula, 、、 And The actual charging power, the discharging power, the actual charging power and the discharging power of the super capacitor of the lithium ion battery at the moment t are respectively; And The actual output power of the fuel cell is respectively the t moment and the t-1 moment; And Respectively 0-1 variables of whether the lithium ion battery is actually charged and discharged at the moment t; And Respectively 0-1 variables of whether the super capacitor is actually charged and discharged at the moment t; And Conversion efficiency of the DC-DC bidirectional converter and the high-speed motor respectively; And The charging efficiency and the discharging efficiency of the lithium ion battery are respectively; And The charging efficiency and the discharging efficiency of the super capacitor are respectively; And The maximum allowable ramp up and ramp down rates of the fuel cell, And The maximum allowable charge and discharge rates of the lithium ion battery, And The maximum allowable charge and discharge rates of the supercapacitor respectively, 、 And The design capacities of lithium ion batteries, supercapacitors and fuel cells, respectively.
10. A machine-readable storage medium, having stored thereon a computing program, the computing program being executable by a processor to perform the method of any of claims 1-9.

Description

Energy management method and storage medium for electric aircraft composite energy system Technical Field The invention relates to the technical field of electric aircraft control, in particular to an energy management method and a storage medium for an electric aircraft composite energy system. Background The development of the electric aircraft technology based on the new energy technology is an effective way for simplifying the aircraft energy structure, improving the energy utilization rate and reliability and reducing the carbon emission. The existing electric aircraft technology is mostly based on a pure lithium ion battery technology, but is limited by the energy density of the lithium ion battery, so that the energy power requirement of a medium-long distance commercial aircraft is difficult to meet. The composite energy system based on the hydrogen storage system, namely the hydrogen fuel cell, the lithium ion battery and the super capacitor can better realize the advantage complementation among energy units, and is a set of feasible scheme for promoting the enlargement of the electric aircraft. However, the flight working conditions of the aircraft are complex and changeable, the characteristics of each unit of the composite energy system are different, the coupling relation is complex, great challenges are brought to the development of an energy management method of the composite energy system, and the safety and the economy of the system are also obviously affected. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide an energy management method and a storage medium for an electric aircraft composite energy system, so that the energy utilization efficiency of the composite energy system energy management is improved. The aim of the invention can be achieved by the following technical scheme: an energy management method of an electric aircraft composite energy system, comprising the steps of: s1, before the electric aircraft takes off, drawing a power demand-time curve of the electric aircraft according to a flight plan of the electric aircraft; S2, constructing an energy optimization scheduling model which takes the energy cost of the composite energy system as an optimization target according to the output characteristics and the operation constraint conditions of each unit of the composite energy system of the electric aircraft; s3, inputting technical parameters of each unit of the electric aircraft and a power demand-time curve into the energy optimization scheduling model, and carrying out model solving to obtain an energy scheduling plan of the composite energy system; and S4, calculating the deviation between the real-time power demand of the electric aircraft and the energy scheduling plan of the composite energy system by taking the energy scheduling plan of the composite energy system as a base line in the real-time flight process of the electric aircraft, and constructing a system energy real-time control model by taking the minimum deviation as an optimization target to obtain an actual energy management strategy of the composite energy system. Further, the power demand-time profile of the electric aircraft includes power demand-time profiles of the electric aircraft during a takeoff phase, a climb phase, a cruise phase, and a landing phase. Further, the composite energy system comprises a hydrogen fuel cell, a lithium ion battery and a super capacitor; during the take-off stage and the climbing stage, the hydrogen fuel cell, the lithium ion battery and the super capacitor are powered together; during the cruise phase and the descent phase, power is supplied by a hydrogen fuel cell and a lithium ion battery. Further, the optimization targets of the energy optimization scheduling model are as follows: Wherein E total is the total energy cost of the electric aircraft composite energy system; And Respectively the residual electric energy of the lithium ion battery and the super capacitor after the flying is finished,AndThe method comprises the steps of respectively obtaining residual electric energy of a lithium ion battery and a super capacitor after the flying is finished, wherein beta ele and beta H are respectively the price of charging and hydrogen charging, P tFC is the output power of a fuel cell system at the time t, eta E,H is an electric hydrogen conversion coefficient, and delta t is an energy management scheduling time interval. Further, the operation constraint conditions comprise bus power balance constraint, energy storage device energy balance constraint, system unit power constraint and system unit energy constraint; The expression of the bus power balance constraint is as follows: in the formula, AndThe charging efficiency, the discharging efficiency and the charging power and the discharging power of the lithium ion battery at the moment t are respectively; And The power supply system comprises a super capacitor, P tFC, P lo