Range-extending hybrid system optimization control method based on demand power predictionTechnical Field
The invention relates to the field of an optimal control method of an extended-range hybrid system, in particular to an optimal control method of an extended-range hybrid system based on demand power prediction.
Background
The range-extending hybrid system is applied to the field of highway freight transportation, the transportation working condition is complex, the range-extending hybrid vehicle is frequently accelerated and braked in the transportation process, the system energy is frequently transmitted and converted, and if the energy supply process of the range-extending hybrid vehicle is not reasonably controlled, a large amount of unnecessary electric energy loss is caused. The single power supply capacity of the power battery is insufficient to meet the energy requirement of the range extender hybrid vehicle during rapid acceleration, so that the range extender is required to be interposed to assist in supplying power to the driving motor when appropriate, and the kinetic energy of the range extender hybrid vehicle during braking can be recovered by the power battery. The optimization control method of the extended range hybrid system has reasonable design, can improve the energy utilization efficiency of the whole system in the running process, and further improves the economical efficiency of the system.
Disclosure of Invention
Therefore, the present invention is directed to an extended range hybrid system optimization control method based on demand power prediction.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
An extended range hybrid system optimization control method based on demand power prediction comprises the following specific steps:
Step one, an optimization controller judges the running state of an extended range hybrid vehicle, determines whether the extended range hybrid vehicle is in a driving state or a braking state, predicts the running required power of the extended range hybrid vehicle, acquires a power generation state of an extended range device and a charge state signal of a power battery, and if the extended range hybrid vehicle is in the driving state, the step two is carried out, and if the extended range hybrid vehicle is in the braking state, the step three is carried out;
Step two, an optimal controller obtains the current driving running state of the range extender hybrid vehicle, and predicts the driving required power of the range extender hybrid vehicle, and the optimal controller obtains the power generation state of the range extender and the charge state signal of the power battery, and determines the power ratio of the power generation of the range extender and the discharge participation driving of the power battery according to a logic algorithm;
And thirdly, judging whether the kinetic energy recovered by the power battery or the synchronous auxiliary charging of the range extender is needed or not by the optimal controller according to the current braking power of the range extender and the state of charge information of the power battery and a logic algorithm, and determining the power ratio of the power generation of the range extender and the recovery of the kinetic energy of the power battery.
The specific process of the first step is as follows:
s101, an optimization controller obtains the current driving running state of the extended range hybrid vehicle;
S102, the optimization controller acquires a required power signal Pm of a driving motor of the extended-range hybrid vehicle, if the required power Pm of the driving motor is positive, the extended-range hybrid vehicle is determined to be in a driving state and is transferred to the step two, and if the required power Pm of the driving motor is negative, the extended-range hybrid vehicle is determined to be in a braking state and is transferred to the step three.
The specific process of the second step is as follows:
S201, an optimization controller obtains the current driving running state of the extended range hybrid vehicle;
s202, an optimization controller predicts driving required power of the extended range hybrid vehicle;
s203, the optimal controller acquires a power generation state of the range extender and a charge state signal of the power battery;
S204, if the state of charge (SOC) of the power battery is within a preset high-efficiency SOC range and the predicted driving required power Pm is smaller than the upper limit Pbs,max of the discharging power of the power battery, the predicted driving required power Pm is provided by the discharging of the power battery;
S205, if the state of charge (SOC) of the power battery is within a preset high-efficiency SOC range and the predicted driving required power Pm is greater than the upper limit Pbs,max of the discharging power of the power battery, the optimal controller sends a control instruction, the power battery starts a maximum power discharging state, and the residual driving required power is provided by discharging of the range extender;
S206, if the state of charge (SOC) of the power battery is smaller than the lower limit value of a preset high-efficiency SOC range and the predicted driving required power Pm is larger than the upper limit Pes,max of the power generation power of the range extender, the optimal controller sends a control instruction, the range extender starts the maximum power generation state, and the residual driving required power is provided by discharging the power battery;
S207, if the state of charge (SOC) of the power battery is smaller than the lower limit value of a preset high-efficiency SOC range and the predicted driving required power Pm is smaller than the upper limit Pes,max of the power generation power of the range extender, the optimization controller sends out a control instruction, and the range extender generates power to provide all required power;
s208, returning to the step one after the driving process is executed.
The specific process of the third step is as follows:
s301, an optimization controller acquires the current driving running state of the extended range hybrid vehicle;
s302, the optimization controller predicts the braking driving demand power of the extended range hybrid vehicle;
S303, if the state of charge (SOC) of the power battery is smaller than a preset maximum value (SOCmax) and the predicted driving required power Pm is larger than the maximum charging power Pbs,c,max of the power battery, the optimal controller sends a control instruction, and the power battery starts the state of charge and recovers the braking energy of the vehicle by the maximum charging power;
S304, if the state of charge SOC of the power battery is smaller than a preset maximum value SOCmax and larger than a preset minimum value SOCmin, and the predicted driving required power Pm is smaller than the maximum charging power Pbs,c,max of the power battery, the optimization controller sends a control instruction, and the power battery starts the state of charge to recover all braking energy;
S305, if the state of charge SOC of the power battery is smaller than a preset minimum value SOCmin and the required power Pm of the driving motor is smaller than the maximum charging power Pbs,c,max of the power battery, the optimization controller sends a control instruction, the power battery is started to fully recover the braking energy in a state of charge, and meanwhile, the range extender is started to synchronously assist in charging, so that the charging power of the power battery reaches the maximum charging power Pbs,c,max to supplement the electric quantity of the power battery;
S306, returning to the first step after the braking process is executed.
Drawings
FIG. 1 is a flowchart of an extended range hybrid system optimization control method based on demand power prediction according to the present invention.
Detailed Description
In order that the above objects, features and advantages of the present invention will be readily apparent, a more particular description of embodiments of the invention will be rendered by reference to the appended drawings, which together with the appended drawings form a part, but not all, of embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.
As shown in FIG. 1, the method for optimizing and controlling the extended range hybrid system based on the demand power prediction comprises the following specific steps:
Step one, an optimization controller judges the running state of an extended range hybrid vehicle, determines whether the extended range hybrid vehicle is in a driving state or a braking state, predicts the running required power of the extended range hybrid vehicle, acquires a power generation state of an extended range device and a charge state signal of a power battery, and if the extended range hybrid vehicle is in the driving state, the step two is carried out, and if the extended range hybrid vehicle is in the braking state, the step three is carried out;
Step two, an optimal controller obtains the current driving running state of the range extender hybrid vehicle, and predicts the driving required power of the range extender hybrid vehicle, and the optimal controller obtains the power generation state of the range extender and the charge state signal of the power battery, and determines the power ratio of the power generation of the range extender and the discharge participation driving of the power battery according to a logic algorithm;
And thirdly, judging whether the kinetic energy recovered by the power battery or the synchronous auxiliary charging of the range extender is needed or not by the optimal controller according to the current braking power of the range extender and the state of charge information of the power battery and a logic algorithm, and determining the power ratio of the power generation of the range extender and the recovery of the kinetic energy of the power battery.
The specific process of the first step is as follows:
s101, an optimization controller obtains the current driving running state of the extended range hybrid vehicle;
S102, the optimization controller acquires a required power signal Pm of a driving motor of the extended-range hybrid vehicle, if the required power Pm of the driving motor is positive, the extended-range hybrid vehicle is determined to be in a driving state and is transferred to the step two, and if the required power Pm of the driving motor is negative, the extended-range hybrid vehicle is determined to be in a braking state and is transferred to the step three.
The specific process of the second step is as follows:
S201, an optimization controller obtains the current driving running state of the extended range hybrid vehicle;
s202, an optimization controller predicts driving required power of the extended range hybrid vehicle;
s203, the optimal controller acquires a power generation state of the range extender and a charge state signal of the power battery;
S204, if the state of charge (SOC) of the power battery is within a preset high-efficiency SOC range and the predicted driving required power Pm is smaller than the upper limit Pbs,max of the discharging power of the power battery, the predicted driving required power Pm is provided by the discharging of the power battery;
S205, if the state of charge (SOC) of the power battery is within a preset high-efficiency SOC range and the predicted driving required power Pm is greater than the upper limit Pbs,max of the discharging power of the power battery, the optimal controller sends a control instruction, the power battery starts a maximum power discharging state, and the residual driving required power is provided by discharging of the range extender;
S206, if the state of charge (SOC) of the power battery is smaller than the lower limit value of a preset high-efficiency SOC range and the predicted driving required power Pm is larger than the upper limit Pes,max of the power generation power of the range extender, the optimal controller sends a control instruction, the range extender starts the maximum power generation state, and the residual driving required power is provided by discharging the power battery;
S207, if the state of charge (SOC) of the power battery is smaller than the lower limit value of a preset high-efficiency SOC range and the predicted driving required power Pm is smaller than the upper limit Pes,max of the power generation power of the range extender, the optimization controller sends out a control instruction, and the range extender generates power to provide all required power;
s208, returning to the step one after the driving process is executed.
The specific process of the third step is as follows:
s301, an optimization controller acquires the current driving running state of the extended range hybrid vehicle;
s302, the optimization controller predicts the braking driving demand power of the extended range hybrid vehicle;
S303, if the state of charge (SOC) of the power battery is smaller than a preset maximum value (SOCmax) and the predicted driving required power Pm is larger than the maximum charging power Pbs,c,max of the power battery, the optimal controller sends a control instruction, and the power battery starts the state of charge and recovers the braking energy of the vehicle by the maximum charging power;
S304, if the state of charge SOC of the power battery is smaller than a preset maximum value SOCmax and larger than a preset minimum value SOCmin, and the predicted driving required power Pm is smaller than the maximum charging power Pbs,c,max of the power battery, the optimization controller sends a control instruction, and the power battery starts the state of charge to recover all braking energy;
S305, if the state of charge SOC of the power battery is smaller than a preset minimum value SOCmin and the required power Pm of the driving motor is smaller than the maximum charging power Pbs,c,max of the power battery, the optimization controller sends a control instruction, the power battery is started to fully recover the braking energy in a state of charge, and meanwhile, the range extender is started to synchronously assist in charging, so that the charging power of the power battery reaches the maximum charging power Pbs,c,max to supplement the electric quantity of the power battery;
S306, returning to the first step after the braking process is executed.