CN-121973752-A - Super capacitor charge and discharge control method and device, working machine and storage medium

CN121973752ACN 121973752 ACN121973752 ACN 121973752ACN-121973752-A

Abstract

The invention relates to the technical field of hybrid power, and discloses a charge and discharge control method, a device, an operation machine and a storage medium of a super capacitor, wherein the invention detects that a hybrid power system is in a target working condition, acquires working condition parameters of the hybrid power system, then determines a charge state protection threshold value of the super capacitor and a control strategy of charge and discharge power based on the working condition parameters and the energy flow direction of corresponding components, and can further determine the charge state protection threshold value of the super capacitor and the control strategy of the charge and discharge power based on the charge state protection threshold value of the super capacitor, the super capacitor is controlled to charge and discharge, so that the charge state of the super capacitor is dynamically maintained in a high-efficiency interval, and the charge and discharge efficiency of the super capacitor is always kept at a higher level, thereby remarkably improving the recovery rate of regenerated energy and the utilization rate of auxiliary driving energy of the super capacitor, effectively avoiding the extreme charge state of the super capacitor, reducing the internal loss and aging rate of the super capacitor, and prolonging the cycle life of the battery.

Inventors

ZHANG JIAN
QI XINGJUN
CHI FENG
HUANG CHUANZONG

Assignees

山东临工工程机械有限公司

Dates

Publication Date: 20260505
Application Date: 20260214

Claims (10)

1. The charge and discharge control method of the super capacitor is characterized by being applied to a hybrid power system, wherein the hybrid power system at least comprises the super capacitor, a generator motor and a rotary motor, and the method comprises the following steps of: In response to detecting that the hybrid power system is in a target working condition, working condition parameters of the hybrid power system are obtained, wherein the working condition parameters at least comprise at least one of output power of a generator motor, load demand power, demand or output power of a rotary motor, and energy flow directions of corresponding components in the generator motor, a super capacitor and the rotary motor; Determining a charge state protection threshold value of the super capacitor and a control strategy of charge and discharge power or determining a control strategy of charge and discharge power of the super capacitor based on the working condition parameters and the energy flow direction of the corresponding components; and controlling the super capacitor to charge and discharge based on a charge state protection threshold value of the super capacitor and a control strategy of charging and discharging power or the control strategy of charging and discharging power.
2. The method of claim 1, wherein when the target condition is a light load condition, the generator motor is in a charged state and charges a super capacitor, and determining a charge state protection threshold and a control strategy of charge and discharge power of the super capacitor based on the operating condition parameters and an energy flow direction of the corresponding component comprises: Determining a first charge state protection threshold value of the super capacitor under a light load working condition, wherein the first charge state protection threshold value is obtained by testing working condition parameters under the light load working condition and charging test data of the super capacitor; Monitoring the current state of charge of the super capacitor, and charging the super capacitor based on the current charging power when the current state of charge is smaller than the first state of charge protection threshold; and when the current charge state is not smaller than the first charge state threshold value, controlling the charging power to gradually decrease to zero, wherein the decreasing process of the charging power comprises decreasing at a first rate and then decreasing at a second rate, and the first rate is larger than the second rate.
3. The method of claim 1, wherein when the target condition is a swing braking condition, the swing motor charges a supercapacitor, and the determining a state of charge protection threshold and a control strategy for charge-discharge power of the supercapacitor based on the operating condition parameters and an energy flow direction of the corresponding component comprises: In response to detecting a rotary motor braking signal, predicting rotary motor braking duration based on a pre-calibrated rotary motor speed curve and a rotary motor speed, wherein the speed curve correlates the rotary motor speed and braking time; Calculating the integral of the super capacitor in the braking time based on a pre-calibrated charging power curve and the charging power of the super capacitor, and determining a reserved state of charge increment value, wherein the charging power curve is related to the braking time and the charging power; The upper limit value of the charge state of the super capacitor is differenced with the increment value of the reserved charge state, and a second charge state protection threshold value of the super charge is obtained; acquiring the current state of charge of the super capacitor; and when the current charge state is smaller than the second charge state protection threshold value, charging the super capacitor based on the charging power curve.
4. A method according to claim 3, characterized in that the method further comprises: And if the current state of charge is greater than the second state of charge protection threshold, controlling the rotary motor to stop charging the super capacitor.
5. The method of claim 1, wherein when the target condition is a heavy load condition and the load demand power is greater than the output power of the generator motor, the generator motor provides energy to the load, the super-capacitor provides energy to the load and the rotating electric machine, the determining the state of charge protection threshold of the super-capacitor and the control strategy of the charge and discharge power based on the operating condition parameters and the energy flow direction of the corresponding components comprises: calculating a state of charge required for a rotation preset angle of the rotation motor, the rotation preset angle corresponding to an angle required for rotating the rotation motor to a normal working position; calculating a difference value between the current state of charge of the super capacitor and the required state of charge, and determining the difference value as a third state of charge protection threshold; when the current state of charge is greater than the third state of charge protection threshold, controlling the super capacitor to provide energy for the load and the rotary motor based on preset discharge power until the current state of charge reaches the state of charge protection threshold; and when the current state of charge reaches the state of charge protection threshold, controlling the super capacitor to provide energy for the rotary motor.
6. The method of claim 1, wherein when the target condition is a heavy load condition and the load demand power is less than the output power of the generator motor, the generator motor provides energy to the load and the super-capacitor, the super-capacitor provides energy to the electric rotating machine, and determining a charging and discharging power control strategy of the super-capacitor based on the operating condition parameters and the energy flow direction of the corresponding components comprises: Acquiring the required power of a rotary motor; Controlling the discharge power of the super capacitor to be equal to the required power of the rotary motor; the output power of the generator motor is controlled to be equal to the sum of the discharge power of the super capacitor and the load demand power.
7. The utility model provides a super capacitor's charge-discharge control device, its characterized in that is applied to hybrid system, hybrid system includes super capacitor, generator motor and gyratory motor at least, the device includes: The working condition parameter acquisition module is used for responding to the detection that the hybrid power system is in a target working condition and acquiring working condition parameters of the hybrid power system, wherein the working condition parameters at least comprise at least one of output power of a generator motor, load demand power, demand or output power of a rotary motor and energy flow directions of corresponding components in the generator motor, a super capacitor and the rotary motor; The strategy determining module is used for determining a charge state protection threshold value of the super capacitor and a control strategy of charging and discharging power or determining a control strategy of charging and discharging power of the super capacitor based on the working condition parameters and the energy flow directions of the corresponding components; And the charge-discharge control module is used for controlling the super capacitor to charge and discharge based on the charge state protection threshold value of the super capacitor and a control strategy of charge and discharge power or the control strategy of charge and discharge power.
8. A work machine comprising a controller including a memory and a processor, the memory and the processor being communicatively coupled to each other, the memory having stored therein computer instructions, the processor executing the computer instructions to perform the method of controlling charging and discharging of the supercapacitor of any one of claims 1 to 6.
9. The work machine of claim 8, wherein the work machine is an excavator.
10. A computer-readable storage medium, wherein computer instructions for causing a computer to execute the method of controlling charge and discharge of the supercapacitor according to any one of claims 1 to 6 are stored on the computer-readable storage medium.

Description

Super capacitor charge and discharge control method and device, working machine and storage medium Technical Field The invention relates to the technical field of hybrid electric vehicles, in particular to a charging and discharging control method and device of a super capacitor, an operation machine and a storage medium. Background At present, the green and intelligent engineering machinery has become a clear development trend, wherein an oil-electricity hybrid excavator is gradually applied as an important technical path, a super capacitor is often used as a key energy storage buffer unit for recovering braking energy and providing instantaneous auxiliary power due to the characteristics of high power density and high discharging speed, however, the main stream management mode of the super capacitor of the existing hybrid excavator is still relatively basic and passive, the core is to use the hybrid excavator as a simple 'energy water tank', start-stop control is performed based on a fixed state-of-charge threshold value, namely, the discharging is limited only when the electric quantity of the super capacitor is too high, the electric quantity is too low, but the state of charge of the super capacitor can passively and randomly fluctuate along with working conditions in actual work, and the system lacks the fine regulation and control capability for actively maintaining the super capacitor in a high-efficiency and reasonable working interval, so that the performance advantage and energy-saving potential of the super capacitor cannot be fully exerted. Disclosure of Invention The invention provides a charge and discharge control method and device of a super capacitor, an operation machine and a storage medium, and aims to solve the problem that the charge state of the super capacitor fluctuates along with working conditions in actual work and lacks of fine regulation and control capability for actively maintaining the super capacitor in a high-efficiency and reasonable working range. In a first aspect, the invention provides a charge-discharge control method of a super capacitor, which is applied to a hybrid power system, wherein the hybrid power system at least comprises the super capacitor, a generator motor and a rotary motor, the method comprises the steps of responding to the fact that the hybrid power system is detected to be in a target working condition, obtaining working condition parameters of the hybrid power system, wherein the working condition parameters at least comprise at least one of output power of the generator motor, load demand power, demand or output power of the rotary motor and energy flow directions of corresponding components in the generator motor, the super capacitor and the rotary motor, determining a charge state protection threshold of the super capacitor and a control strategy of charge-discharge power or determining a charge-discharge power control strategy of the super capacitor based on the working condition parameters and the energy flow directions of the corresponding components, and controlling the super capacitor to charge and discharge based on the charge state protection threshold of the super capacitor and the control strategy of charge-discharge power or the charge-discharge power control strategy. According to the charging and discharging control method of the super capacitor, provided by the invention, the working condition parameters of the hybrid power system are obtained in response to the detection that the hybrid power system is in the target working condition, then the charge state protection threshold value and the control strategy of charging and discharging power of the super capacitor are determined based on the working condition parameters and the energy flow direction of the corresponding components, or the charging and discharging power control strategy of the super capacitor is determined, then the super capacitor is controlled to charge and discharge based on the charge state protection threshold value and the control strategy of charging and discharging power of the super capacitor, so that the charge state of the super capacitor is dynamically maintained in a high-efficiency interval, the charge and discharging efficiency of the super capacitor is always kept at a higher level, the recovery rate of regenerated energy and the utilization rate of auxiliary driving energy of the super capacitor are remarkably improved, the extreme charge state of the super capacitor is effectively avoided, the internal loss and the aging rate of the super capacitor are reduced, and the cycle life of the battery is prolonged. In an alternative implementation mode, when the target working condition is a light-load working condition, the generator motor is in a charging state, the super capacitor is charged, a charging state protection threshold and a charging and discharging power control strategy of the super capacitor are determined based on the working condition