A power adaptive control method, medium and system for hybrid electric locomotive

Abstract

The present invention discloses a power adaptive control method, medium and system for a hybrid electric locomotive. The method comprises the following steps: 1) obtaining the intermediate DC voltage U of the busbar 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 the preset power reduction target voltage U tration Compare; where U tration bat_discharge bat_charge ; when U real >U bat_charge , then enter the charging mode; when U real <U bat_discharge , then enter the discharge mode; when U real <U bat_discharge , then go to step 3); 3) Traction power control process: obtain the preset power reduction target voltage U tration and busbar intermediate DC voltage 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 the actual traction power P in the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to the traction power setting value P in this cycle. set The present invention has the advantages of simple control and high power distribution efficiency.​​

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 a hybrid electric locomotive. Background Art

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

[0003] 1. All used for backend load;

[0004] 2. Part of the power is used for the back-end load and part 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 back-end load varies with the operating conditions, it is necessary to rationally allocate the power of the diesel engine and power battery to save energy. Currently, the control of hybrid power operation is generally achieved by collecting battery status parameters, diesel engine status parameters, and back-end operating load conditions, calculating and allocating the power of each power source in advance, and controlling the charge and discharge mode of the power battery charger through instructions. The control algorithm is complex and the power allocation efficiency is relatively low. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: in response to 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 busbar 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 the preset power reduction target voltage U tration Compare; where U tration bat_discharge bat_charge ;

[0010] When U real ​​>U bat_charge , then enter the charging mode; when U real <U bat_discharge , then enter 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 and busbar intermediate DC voltage 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 the actual traction power P in the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to the traction power setting value P in this cycle. set .

[0012] Preferably, in step 3), according to the difference e p_tration The specific formula for obtaining the increase or decrease in traction power ΔP(k) during 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) Control the duty cycle of the actual battery charge and discharge in the previous cycle to PWM bat_last Add the final increase or decrease ΔB(k) as the duty cycle PWM setting for battery charge and discharge in 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 value 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] 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 value 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] 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] 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 as follows:

[0029] S1. Obtain the dPID excitation control duty cycle increase or decrease ΔI based on the intermediate DC voltage u (k), and the dPID excitation control duty cycle increase or decrease ΔI based on the diesel engine power 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 increase or decrease of the duty cycle 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 value 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] 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 value 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 of the diesel engine P 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] Kp1, Ki1, and 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 power adaptive control system for a hybrid electric locomotive, 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 above method are executed.

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

[0044] The power adaptive control method, medium, and system for a hybrid electric locomotive of the present invention monitors the intermediate DC voltage value of the busbar of the hybrid electric locomotive in real time, compares the intermediate DC voltage value of the busbar with different voltage thresholds, and automatically switches the charging and discharging of the power battery charger based on the comparison results, while also controlling the traction power based on the comparison results. The above method is simple to control and has 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 FIG. 4 is a topological diagram of an embodiment of a hybrid electric locomotive according to the present invention.

[0047] Figure 3 It is a flow chart of the control method of the present invention in an embodiment. DETAILED DESCRIPTION

[0048] The present invention will be further described below with reference to 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 includes the following steps:

[0050] 1) Obtain the busbar 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 the preset power reduction target voltage U tration Compare; where U tration <Ubat_discharge bat_charge ;

[0052] When U real >U bat_charge , then enter the charging mode; when U real <U bat_discharge , then enter 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 and busbar intermediate DC voltage 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 the actual traction power P in the previous cycle is calculated. last Add the increase or decrease of traction power in this cycle ΔP(k) to the traction power setting value P in this cycle. set =P last +ΔP(k). Specifically, according to the difference e p_tration The specific formula for obtaining the increase or decrease in traction power ΔP(k) during 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 for a hybrid electric locomotive of the present invention monitors the intermediate DC voltage value of the busbar of the hybrid electric locomotive in real time, compares the intermediate DC voltage value of the busbar with different voltage thresholds, and automatically switches the charging and discharging of the power battery charger based on the comparison results, and simultaneously controls the traction power based on the comparison results. The above method is simple to control and has high power distribution efficiency.

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

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

[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] 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 of the diesel engine P 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] Kp1, Ki1, and 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 increase or decrease of the duty cycle 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 increase or decrease of the duty cycle 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] 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 realCalculate the increase or decrease of the battery power control duty cycle ΔB in this cycle u (k);

[0078]

[0079] 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) Control the duty cycle of the actual battery charge and discharge in the previous cycle to PWM bat_last Add the final increase or decrease ΔB(k) as the duty cycle PWM setting for battery charge and discharge in this cycle bat_set , controls 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 in the figure, under the generator-powered operating condition, the three-phase voltage input by the main generator is rectified to an 1800V DC voltage through a three-phase uncontrolled rectifier; under the battery-powered operating condition, the DC voltage input by the battery is boosted to an 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 the braking operating condition, the three-phase voltage emitted by the traction motor can be used to charge the battery 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 in the DC circuit and rapid discharge after shutdown.

[0085] An embodiment of the present invention also discloses a computer-readable storage medium having a computer program stored thereon. When executed by a processor, the computer program performs the steps of the above-described method. An embodiment of the present invention further discloses a power adaptive control system for a hybrid electric locomotive, comprising a memory and a processor connected to each other. The memory stores a computer program. When executed by the processor, the computer program performs the steps of the above-described method. The present invention can implement all or part of the process steps of the above-described method by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the above-described method embodiment. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. Computer-readable media include any entity or device capable of carrying computer program code, recording media, USB flash drives, removable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunications signals, and software distribution media. 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 accessing the data stored in the memory. The memory may include high-speed random access memory (RAM) and non-volatile memory, such as a hard disk, internal memory, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0086] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A power adaptive control method for a hybrid electric locomotive, characterized in that: Including steps: 1) Obtaining the DC voltage of the busbar of a hybrid electric locomotive ; 2) The busbar intermediate DC voltage Respectively with the preset charging target voltage , preset discharge target voltage and preset power reduction target voltage To compare; < < ; when , then enter the charging mode; when , it enters the discharge mode; when , then go to step 3); 3) Traction power control process: Obtaining the preset power reduction target voltage and busbar intermediate DC voltage The difference between , and then according to the difference Get the increase or decrease of traction power in this cycle , and then the actual traction power of the previous cycle Add the increase or decrease in traction power during this cycle , as the traction power setting value of this cycle .

2. The power adaptive control method for a hybrid electric locomotive according to claim 1, characterized in that: In step 3), based on the difference Get the increase or decrease of traction power in this cycle The specific formula is: in 、 、 is the PID parameter value; 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 for 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 based on the intermediate DC voltage , and the dPID power battery power control duty cycle increase or decrease based on the power battery current ; 2.2) and Compare and select the smaller one as the final increase or decrease ; 2.3) Control the duty cycle of the actual battery charge and discharge in the previous cycle Add the final increase or decrease , as the battery charge and discharge duty cycle setting for this cycle , control the battery charging and discharging power.

4. The power adaptive control method for 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 based on the intermediate DC voltage The specific process is: according to and the preset intermediate DC voltage threshold ,get and The difference between , calculate the increase or decrease of the power battery power control duty cycle in this cycle ; in 、 、 is the PID parameter value; 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 for 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 based on the power battery current The specific process is: Get the actual charge and discharge current of the power battery ; Set the preset charge and discharge current target value of the power battery and Compare and get the current difference , calculate the increase or decrease of the power battery power control duty cycle in this cycle : in 、 、 is the PID parameter value; 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 for a hybrid electric locomotive according to claim 1 or 2, characterized in that: Before step 2), excitation control is also included. The specific process is as follows: S1. Obtain the increase or decrease of the dPID excitation control duty cycle based on the intermediate DC voltage , and the dPID excitation control duty cycle increase or decrease based on diesel engine power ; S2, will and Compare and select the smaller one as the final increase or decrease of duty cycle ; S3, the actual output duty cycle of the previous cycle Add the final increase or decrease in duty cycle , as the duty cycle setting value of this cycle , control the main generator excitation current.

7. The power adaptive control method for a hybrid electric locomotive according to claim 6, characterized in that: In step S1, the dPID excitation control duty cycle increase or decrease based on the intermediate DC voltage is obtained. The specific process is: Set the preset bus intermediate DC voltage threshold and Compare and get the difference , calculate the increase or decrease of the excitation duty cycle in this cycle ; in 、 、 is the PID parameter value; 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 for a hybrid electric locomotive according to claim 6, characterized in that: In step S1, the dPID excitation control duty cycle increase or decrease based on the diesel engine power is obtained. The specific process is: Get the actual power of the diesel engine as ; The target power of the diesel engine and Compare and get the difference , and then calculate the increase or decrease of the excitation duty cycle in this cycle based on the difference ; in 、 、 is the PID parameter value, 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: When the computer program is executed by a processor, the computer program performs the steps of the method according to any one of claims 1 to 8.

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: When the computer program is executed by a processor, the computer program performs the steps of the method according to any one of claims 1 to 8.

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