Hybrid power source energy management method of fuel battery

Abstract

The present invention provides a fuel cell hybrid power management method, including steps: initialization; the actual current of the measured energy device and the output of the DCDC transformation unit to control the output current of the DCDC change unit, the energy caused by changes in the load state changesDemand, while ensuring the storage device in the best load state; sending the current settings instructions to the DCDC transformation unit.The present invention no longer adopts the SOC computing mode, and the system no longer depends on the accuracy and reliability of the sensor of the current; and the present invention is strong, highly reliable, strong, and stable output voltage. The same system can be applied to more for more.Different vehicles (forklifts) of different models do not require correction parameters. By setting up parameters in advance, the battery capacity decreases back in advance to ensure the long -term reliability of the system.

Description

technical field [0001] The invention relates to a fuel cell, in particular to a fuel cell hybrid power source energy management method. Background technique [0002] After searching the prior art, the following documents were retrieved: [0003] The fuel cell power supply control principle disclosed in the Chinese invention patent application with the application number "200310103253.3" and the name "Power Distribution Method for Fuel Cell Hybrid Power System" is: use SOC calculation, control signal (such as throttle signal) according to the measured load and the power battery SOC (state of charge) to control the output of the fuel cell DCDC to meet the energy demand of the load system, fuel cell system and power battery pack state of charge. [0004] The fuel cell power supply control method disclosed in the Chinese invention patent application with the application number "201010108281.4" and the name "Energy Management System for Fuel Cell-Based Hybrid Power Plant" also u...

AI Technical Summary

Problems solved by technology

[0009] 1. The above control methods all rely on SOC calculation; the accuracy of SOC calculation depends on accurate current data, and the accuracy of current data depends on the accuracy, sensitivity, and stability of current measurement devices; however, current measurement devices also exist error; therefore, the SOC calculation method can only approximate the state of charge of the energy storage device

The existing vehicle-mounted fuel cell system using the SOC calculation method uses a dual-range current sensor in order to obtain a relatively accurate current value; however, the dual-range current sensor cannot accurately cover the full range, and at the same time cannot avoid the zero point of the current sensor drift, so the current sensor needs to be calibrated frequently

In this case, after the fuel cell company sells the on-board fuel cell system, it has to periodically calibrate the sensor of the current measuring device. The immaturity of the product will directly affect the marketization process of the fuel cell vehicle

[0010] 2. The capacity of the energy storage device (battery) will gradually decrease with use. It can be seen from the formula that in order to obtain an accurate SOC, it is necessary to have an accurate value of the capacity of the energy storage device

Therefore, the SOC calculation method cannot accurately manage the energy of the fuel cell system

[0011] 3. The current output fluctuates greatly when the forklift is working

The current range is large, and it is difficult to accurately measure the current value; at the same time, the high fluctuation frequency of the current output when the forklift is working further makes it very difficult to measure the current accurately in real time; and the SOC integration algorithm will continue to amplify the deviation

Therefore, it is impossible to accurately manage the energy of the fuel cell system by using the SOC calculation method on the fuel cell forklift

[0014] 4. The problem of energy recovery and protection

[0016] However, the SOC calculation is based on the measured battery current value and the actual capacity of the battery. Since the battery current data and the actual capacity of the battery cannot be accurately measured, the SOC calculation method cannot obtain the actual SOC value. When the SOC measurement value is lower than the actual value , the actual state of charge (SOC) of the energy storage device is at a relatively high value, and the voltage of the energy storage device will exceed the protection voltage of the energy storage device or the protection voltage of the vehicle; this will pose a safety hazard to fuel cell vehicles

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