Power self-adaptive control method, medium and system for oil-electric hybrid power locomotive

Abstract

The invention discloses a power self-adaptive control method, medium and system for an oil-electric hybrid power locomotive. The method comprises the following steps: 1) acquiring bus intermediate direct-current voltage Ureal of the oil-electric hybrid power locomotive; (2) the bus intermediate direct-current voltage Ureal is compared with a preset charging target voltage Ubatcharge, a preset discharging target voltage Ubatcharge and a preset power reduction target voltage Utrage respectively, and the preset charging target voltage Ubatcharge, the preset discharging target voltage Ubatcharge and the preset power reduction target voltage Utrage are compared with the preset charging target voltage Ubatcharge and the preset power reduction target voltage Utrage respectively; wherein the Utragiont is the Utragiont; the method comprises the following steps of: obtaining a Ubatdischargult; the method comprises the following steps of: performing Ubatcharge; when the Ureal is greater than the Ubatch, entering a charging mode; when the Ureal is less than the Ubatdisk, entering a discharge mode; when the Ureal is less than the Ubatdisk, entering the step 3), and when the Ureal is less than the Ubatdisk, entering the step 3); and 3) a traction power control process: obtaining a difference value eptration between a preset power reduction target voltage Utration and a bus intermediate direct current voltage Ureal, obtaining a traction power increase and decrease amount delta P (k) of the current period according to the difference value eptration, and adding the traction power increase and decrease amount delta P (k) of the current period to the actual traction power Plaast of the previous period to obtain a traction power set value Pset of the current period. The method has the advantages of simple control, high power distribution efficiency and the like.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of locomotive power control, and in particular to a power adaptive control method, medium and system for an oil-electric hybrid locomotive. Background Art

[0002] At present, the power source of hybrid locomotives is generally a combination of diesel engines and power batteries. The working conditions are generally pure diesel engine, pure electric, and oil-electric mixed conditions. In pure diesel engine conditions, only the diesel engine provides power and is controlled as a pure diesel engine AC transmission locomotive; in pure electric conditions, the rear-end output load is planned according to the power battery conditions; in oil-electric mixed conditions, the power output of the diesel engine may be in the following situations:

[0003] 1. All used for backend load;

[0004] 2. Part of it is used for the rear-end load, and part of it is used to charge the power battery. Because the power of the power battery changes dynamically with parameters such as SOC, the power of the diesel engine changes with parameters such as speed, and the rear-end load changes with the working conditions, it is necessary to reasonably allocate the power of the diesel engine and the power battery to save energy. At present, the control of the oil-electric hybrid working condition is generally carried out by collecting battery state parameters, diesel engine state parameters and rear-end working condition load conditions, and through calculation, the power of each power source is planned and allocated in advance, and the charging and discharging mode of the power battery charger is controlled through instructions. The control algorithm is complex and the power allocation efficiency is low. Summary of the invention

[0005] The technical problem to be solved by the present invention is: in view of the technical problems existing in the prior art, the present invention provides a power adaptive control method, medium and system for a hybrid electric locomotive with simple control and high power distribution efficiency.

[0006] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0007] A power adaptive control method for a hybrid electric locomotive comprises the following steps:

[0008] 1) Obtain the bus intermediate DC voltage U of the hybrid electric locomotive real ;

[0009] 2) The busbar intermediate DC voltage U real Respectively with the preset charging target voltage U bat_charge , preset discharge target voltage U bat_discharge and preset power reduction target voltage U tration For comparison; tration bat_discharge bat_charge ;

[0010] When U real ​​>U bat_charge , then enter the charging mode; when U real <U bat_discharge , it enters the discharge mode; when U real <U bat_discharge , then go to step 3);

[0011] 3) Traction power control process: Obtaining the preset power reduction target voltage U tration The DC voltage between the busbars U real The difference between p_tration , and then according to the difference e p_tration The increase or decrease of traction power in this cycle ΔP(k) is obtained, and then the actual traction power P of the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to take the traction power setting value P of this cycle. set .

[0012] Preferably, in step 3), according to the difference e p_tration The specific formula for obtaining the increase or decrease of traction power ΔP(k) in this cycle is:

[0013] ΔP(k)=KP5*[e p_tration (k)-e p_tration (k-1)]+Ki5*e p_tration (k)+Kd5*[e p_tration (k)-2e p_tration (k-1)+e p_tration (k-2)]

[0014] Kp5, Ki5, and Kd5 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0015] Preferably, in step 2), in the charging mode and the discharging mode, the corresponding control process is:

[0016] 2.1) Obtain the dPID power battery power control duty cycle increase or decrease ΔB based on the intermediate DC voltage u (k), and the dPID power battery power control duty cycle increase or decrease ΔB based on the power battery current I (k);

[0017] 2.2) ΔB u (k) and ΔB I (k) and select the smaller one as the final increase or decrease ΔB(k);

[0018] 2.3) The actual battery charge and discharge control duty cycle PWM of the previous cycle bat_last Add the final increase or decrease ΔB(k) as the battery charge and discharge duty cycle PWM setting for this cyclebat_set , control the battery charging and discharging power.

[0019] Preferably, in step 2.1), the dPID power battery power control duty cycle increase or decrease ΔB based on the intermediate DC voltage is obtained. u The specific process of (k) is as follows:

[0020] According to U real and the preset intermediate DC voltage threshold value U bat , get U bat with U real The difference between u_bat , calculate the increase or decrease of the battery power control duty cycle ΔB in this cycle u (k);

[0021]

[0022] Among them, Kp4, Ki4, and Kd4 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0023] Preferably, in step 2.1), the dPID power battery power control duty cycle increase or decrease ΔB based on the power battery current is obtained. I The specific process of (k) is as follows:

[0024] Get the actual charge and discharge current I of the power battery bat_real ;

[0025] Set the preset charge and discharge current target value I bat with I bat_real Compare and get the current difference e I_bat , calculate the increase or decrease of the power battery power control duty cycle ΔB in this cycle I (k):

[0026]

[0027] Among them, Kp3, Ki3, and Kd3 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0028] Preferably, before step 2), excitation control is also included, and the specific process is:

[0029] S1. Obtain the dPID excitation control duty cycle increase or decrease ΔI based on the intermediate DC voltage u (k), and the duty cycle increase or decrease of dPID excitation control based on diesel engine power ΔI p (k);

[0030] S2, ΔI u (k) and ΔIp (k) and select the smaller one as the final duty cycle increase or decrease ΔI(k);

[0031] S3, the actual output duty cycle PWM of the previous cycle last Add the final duty cycle increase or decrease ΔI(k) as the duty cycle setting value PWM for this cycle set , control the main generator excitation current.

[0032] Preferably, in step S1, the dPID excitation control duty cycle increase / decrease amount ΔI based on the intermediate DC voltage is obtained. u The specific process of (k) is as follows:

[0033] Set the preset busbar intermediate DC voltage threshold value U disel with U real Compare and get the difference e u (k) = U disel -U real , calculate the increase or decrease of the excitation duty cycle ΔI in this cycle u (k);

[0034] ΔI u (k) = KP2*[e u (k)-e u (k-1)]+Ki2*e u (k)+Kd2*[e u (k)-2e u (k-1)+e u (k-2)]

[0035] Among them, KP2, Ki2, and Kd2 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0036] Preferably, in step S1, the dPID excitation control duty cycle increase / decrease amount ΔI based on the diesel engine power is obtained. p The specific process of (k) is as follows:

[0037] Get the actual power of the diesel engine as P real ;

[0038] The target power P of the diesel engine disel With P real Compare and get the difference e p (k) = P disel -P real , and then calculate the increase or decrease of the excitation duty cycle ΔI in this cycle based on the difference p (k);

[0039]

[0040] Among them, Kp1, Ki1, Kd1 are PID parameter values, k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0041] The present invention also discloses a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described above are executed.

[0042] The present invention further discloses a hybrid electric locomotive power adaptive control system, comprising a memory and a processor connected to each other, wherein the memory stores a computer program, and when the computer program is run by the processor, the steps of the method described above are executed.

[0043] Compared with the prior art, the advantages of the present invention are:

[0044] The power adaptive control method, medium and system of the hybrid electric locomotive of the present invention monitors the intermediate DC voltage value of the bus of the hybrid electric locomotive in real time, compares the intermediate DC voltage value of the bus with different voltage thresholds, and automatically switches the charging and discharging of the power battery charger according to the comparison result, and at the same time controls the traction power according to the comparison result; the above method has simple control and high power distribution efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The figure is a flow chart of a power allocation method in the prior art.

[0046] Figure 2 It is a topological structure diagram of the hybrid electric locomotive in the present invention in an embodiment.

[0047] Figure 3 The flowchart of the control method of the present invention is an embodiment. DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0049] like Figure 3 As shown, the power adaptive control method of a hybrid electric locomotive according to an embodiment of the present invention comprises the following steps:

[0050] 1) Obtain the bus intermediate DC voltage U of the hybrid electric locomotive real ;

[0051] 2) The busbar intermediate DC voltage U real Respectively with the preset charging target voltage U bat_charge , preset discharge target voltage U bat_discharge and preset power reduction target voltage U tration For comparison; tration <Ubat_discharge bat_charge ;

[0052] When U real >U bat_charge , then enter the charging mode; when U real <U bat_discharge , it enters the discharge mode; when U real <U bat_discharge , then go to step 3);

[0053] 3) Traction power control process: Obtaining the preset power reduction target voltage U tration The DC voltage between the busbars U real The difference between p_tration (k) = U tration -U real , and then according to the difference e p_tration The increase or decrease of traction power in this cycle ΔP(k) is obtained, and then the actual traction power P of the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to take the traction power setting value P of this cycle. set =P last +ΔP(k). Specifically, according to the difference e p_tration The specific formula for obtaining the increase or decrease of traction power ΔP(k) in this cycle is:

[0054] ΔP(k)=KP5*[e p_tration (k)-e p_tration (k-1)]+Ki5*e p_tration (k)+Kd5*[e p_tration (k)-2e p_tration (k-1)+e p_tration (k-2)]

[0055] Kp5, Ki5, and Kd5 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0056] The power adaptive control method of the hybrid electric locomotive of the present invention monitors the intermediate DC voltage value of the bus of the hybrid electric locomotive in real time, compares the intermediate DC voltage value of the bus with different voltage thresholds, and realizes automatic switching of charging and discharging of the power battery charger according to the comparison result, and at the same time realizes control of the traction power according to the comparison result; the above method is simple to control and has high power distribution efficiency.

[0057] In a specific embodiment, before step 2), excitation control is also included, and the specific process is:

[0058] S1. Obtain the dPID excitation control duty cycle increase or decrease ΔI based on the intermediate DC voltage u ​(k), and the duty cycle increase or decrease of dPID excitation control based on diesel engine power ΔI p (k);

[0059] The dPID excitation control duty cycle increase or decrease ΔI based on the intermediate DC voltage is obtained u The specific process of (k) is as follows:

[0060] Set the preset bus intermediate DC voltage threshold value U disel with U real Compare and get the difference e u (k) = U disel -U real , calculate the increase or decrease of the excitation duty cycle ΔI in this cycle u (k);

[0061] ΔI u (k) = KP2*[e u (k)-e u (k-1)]+Ki2*e u (k)+Kd2*[e u (k)-2e u (k-1)+e u (k-2)]

[0062] Among them, KP2, Ki2, and Kd2 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0063] The dPID excitation control duty cycle increase or decrease ΔI based on the diesel engine power is obtained p The specific process of (k) is as follows:

[0064] Get the actual power of the diesel engine as P real ;

[0065] The target power P of the diesel engine disel With P real Compare and get the difference e p (k) = P disel -P real , and then calculate the increase or decrease of the excitation duty cycle ΔI in this cycle based on the difference p (k);

[0066]

[0067] Among them, Kp1, Ki1, Kd1 are PID parameter values, k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0068] S2, ΔI u (k) and ΔI p(k) and compare them, and select the smaller one as the final duty cycle increase or decrease amount ΔI(k) = MIN[ΔI p (k),ΔI u (k)];

[0069] S3, the actual output duty cycle PWM of the previous cycle last Add the final duty cycle increase or decrease ΔI(k) as the duty cycle setting value PWM for this cycle set , controls the main generator excitation current; PWM set =PWM last +ΔI(k).

[0070] In a specific embodiment, in step 2), in the charging mode and the discharging mode, the corresponding control process is:

[0071] 2.1) Obtain the dPID power battery power control duty cycle increase or decrease ΔB based on the intermediate DC voltage u (k), and the dPID power battery power control duty cycle increase or decrease ΔB based on the power battery current I (k);

[0072] Where ΔB is obtained I The specific process of (k) is as follows:

[0073] Get the actual charge and discharge current I of the power battery bat_real ;

[0074] Set the preset charge and discharge current target value I bat with I bat_real Compare and get the current difference e I_bat (k) = I bat -I bat_real , calculate the increase or decrease of the power battery power control duty cycle ΔB in this cycle I (k):

[0075]

[0076] Kp3, Ki3, and Kd3 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0077] Where ΔB is obtained u The specific process of (k) is as follows: real and the preset intermediate DC voltage threshold value U bat , get U bat with U real The difference between u_bat (k) = U bat -U real, calculate the increase or decrease of the battery power control duty cycle ΔB in this cycle u (k);

[0078]

[0079] Among them, Kp4, Ki4, and Kd4 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

[0080] 2.2) ΔB u (k) and ΔB I (k) and compare them, and select the smaller one as the final increase or decrease ΔB(k) = MIN[ΔB p (k),ΔB u (k)];

[0081] 2.3) The actual battery charge and discharge control duty cycle PWM of the previous cycle bat_last Add the final increase or decrease ΔB(k) as the battery charge and discharge duty cycle PWM setting for this cycle bat_set , control the battery charging and discharging power; PWM bat_set =PWM bat_last +ΔI(k).

[0082] In a specific embodiment, the bus intermediate DC voltage chopping target is set to U resis , if the busbar intermediate DC voltage U real >U resis , the chopper is turned on and the energy is consumed by the braking resistor through chopping.

[0083] In the above method, the corresponding voltage magnitude relationship is U resis >U disel >U bat_charge >U bat >U bat_discharge >U tration .

[0084] like Figure 1 As shown, under the condition of generator power supply, the three-phase voltage input by the main generator is rectified into a 1800V DC voltage through a three-phase uncontrolled rectifier; under the condition of battery power supply, the DC voltage input by the battery is boosted to a 1800V DC voltage through a charger, and then inverted into a three-phase VVVF voltage through inverters INV1-INV6 to supply the traction motor; under braking condition, the three-phase voltage emitted by the traction motor can be used for battery charging after rectification, and the excess electric energy is consumed in the braking resistor through the chopper bridge arm integrated in the rectifier. At the same time, the braking resistor can also be used for overvoltage suppression of the DC circuit and rapid discharge after shutdown.

[0085] The embodiment of the present invention also discloses a computer-readable storage medium, on which a computer program is stored, and the computer program executes the steps of the above method when it is executed by a processor. The embodiment of the present invention further discloses a power adaptive control system for a hybrid electric locomotive, including a memory and a processor connected to each other, and the memory stores a computer program, and the computer program executes the steps of the above method when it is executed by the processor. The present invention implements all or part of the process in the above embodiment method, and can also be completed by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above method embodiment when it is executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. Computer-readable media include: any entity or device that can carry computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium, etc. The memory is used to store computer programs and / or modules. The processor implements various functions by running or executing the computer programs and / or modules stored in the memory, and calling the data stored in the memory. The memory may include a high-speed random access memory, and may also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices, etc.

[0086] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A power adaptive control method for a hybrid electric locomotive, characterized in that: Includes steps: 1) Obtain the bus intermediate DC voltage U of the hybrid electric locomotive real ; 2) The busbar intermediate DC voltage U real Respectively with the preset charging target voltage U bat_charge , preset discharge target voltage U bat_discharge and preset power reduction target voltage U tration For comparison; tration bat_discharge bat_charge ;​​ When U real >U bat_charge , then enter the charging mode; when U real <U bat_discharge , it enters the discharge mode; when U real <U bat_discharge , then go to step 3); 3) Traction power control process: Obtaining the preset power reduction target voltage U tration The DC voltage between the busbars U real The difference between p_tration , and then according to the difference e p_tration The increase or decrease of traction power in this cycle ΔP(k) is obtained, and then the actual traction power P of the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to take the traction power setting value P of this cycle. set .

2. The power adaptive control method of a hybrid electric locomotive according to claim 1, characterized in that: In step 3), according to the difference e p_tration The specific formula for obtaining the increase or decrease of traction power ΔP(k) in this cycle is: ΔP(k)=KP5*[e p_tration (k)–e p_tration (k−1)]+K5*e p_tration (k)+Kd5*[e p_tration (k)–2e p_tration (k−1)+e p_tration (k-2)] Kp5, Ki5, and Kd5 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

3. The power adaptive control method of a hybrid electric locomotive according to claim 1 or 2, characterized in that: In step 2), in the charging mode and the discharging mode, the corresponding control process is: 2.1) Obtain the dPID power battery power control duty cycle increase or decrease ΔB based on the intermediate DC voltage u (k), and the dPID power battery power control duty cycle increase or decrease ΔB based on the power battery current I (k); 2.2) ΔB u (k) and ΔB I (k) and select the smaller one as the final increase or decrease ΔB(k); 2.3) The actual battery charge and discharge control duty cycle PWM of the previous cycle bat_last Add the final increase or decrease ΔB(k) as the battery charge and discharge duty cycle PWM setting for this cycle bat_set , control the battery charging and discharging power.

4. The power adaptive control method of a hybrid electric locomotive according to claim 3, characterized in that: In step 2.1), obtain the dPID power battery power control duty cycle increase or decrease ΔB based on the intermediate DC voltage u The specific process of (k) is as follows: According to U real and the preset intermediate DC voltage threshold value U bat , get U bat with U real The difference between u_bat , calculate the increase or decrease of the battery power control duty cycle ΔB in this cycle u (k); Among them, Kp4, Ki4, and Kd4 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

5. The power adaptive control method of a hybrid electric locomotive according to claim 3, characterized in that: In step 2.1), obtain the dPID power battery power control duty cycle increase or decrease ΔB based on the power battery current I The specific process of (k) is as follows: Get the actual charge and discharge current I of the power battery bat_real ; Set the preset charge and discharge current target value I bat with I bat_real Compare and get the current difference e I_bat , calculate the increase or decrease of the power battery power control duty cycle ΔB in this cycle I (k): Kp3, Ki3, and Kd3 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

6. The power adaptive control method of a hybrid electric locomotive according to claim 1 or 2, characterized in that: Before step 2), excitation control is also included, and the specific process is as follows: S1. Obtain the dPID excitation control duty cycle increase or decrease ΔI based on the intermediate DC voltage u (k), and the duty cycle increase or decrease of dPID excitation control based on diesel engine power ΔI p (k); S2, ΔI u (k) and ΔI p (k) and select the smaller one as the final duty cycle increase or decrease ΔI(k); S3, the actual output duty cycle PWM of the previous cycle last Add the final duty cycle increase or decrease ΔI(k) as the duty cycle setting value PWM for this cycle set , control the main generator excitation current.

7. The power adaptive control method of a hybrid electric locomotive according to claim 6, characterized in that: In step S1, the dPID excitation control duty cycle increase / decrease amount ΔI based on the intermediate DC voltage is obtained. u The specific process of (k) is as follows: Set the preset bus intermediate DC voltage threshold value U disel with U real Compare and get the difference e u (k) = U disel -U real , calculate the increase or decrease of the excitation duty cycle ΔI in this cycle u (k); ΔI u (k)=KP2*[e u (k)-e u (k-1)]+Ki2*e u (k)+Kd2*[e u (k)-2e u (k-1)+e u (k-2)] Among them, KP2, Ki2, and Kd2 are PID parameter values; k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

8. The power adaptive control method of a hybrid electric locomotive according to claim 6, characterized in that: In step S1, the dPID excitation control duty cycle increase / decrease amount ΔI based on the diesel engine power is obtained. p The specific process of (k) is as follows: Get the actual power of the diesel engine as P real ; The target power P of the diesel engine disel With P real Compare and get the difference e p (k) = P disel -P real , and then calculate the increase or decrease of the excitation duty cycle ΔI in this cycle based on the difference p (k); Among them, Kp1, Ki1, Kd1 are PID parameter values, k is the current cycle, k-1 is the previous cycle, and k-2 is the cycle before that.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program executes the steps of the method according to any one of claims 1 to 8 when executed by a processor.

10. A power adaptive control system for a hybrid electric locomotive, comprising a memory and a processor connected to each other, wherein a computer program is stored in the memory, characterized in that: The computer program executes the steps of the method according to any one of claims 1 to 8 when executed by a processor.

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