Fuel cell/lithium ion battery hybrid power energy management system used for electric bicycle

Abstract

The invention discloses a fuel cell / lithium ion battery hybrid power energy management system used for an electric bicycle, which comprises an energy management unit, which controls a fuel cell system unit to charge a lithium ion batter unit, controls a hybrid power system to supply power to the external, and is electrically connected with the fuel cell system unit and the lithium ion battery unit respectively. The energy management system reliably clamps the output power of the fuel cell unit in real time, optimizes the output performance of the fuel cell system unit, estimates the under-voltage float charge voltage of the lithium ion batter unit in real time on the base of the working temperature of the lithium ion batter, avoids over charge of the lithium ion battery on the premise of reducing the capacity loss of the lithium ion battery, can improve the float charge safety of the lithium ion battery unit, and further improves the overall safety and the economy of the fuel cell / lithium ion battery hybrid power electric bicycle system.

Description

technical field [0001] The invention relates to a fuel cell / lithium ion battery hybrid energy management system for an electric bicycle. Background technique [0002] With the continuous increase of people's demand for green travel and the continuous enhancement of environmental protection awareness, fuel cell / lithium-ion battery electric bicycles characterized by lightness, flexibility, energy saving and environmental protection have gradually entered people's field of vision. At present, the rated voltage of the DC motor of the electric bicycle is usually 36V and 48V, so in this low-voltage DC application, the main system of the fuel cell / lithium-ion battery hybrid power system is on the output DC bus of the fuel cell cascaded DC converter When the lithium-ion battery pack is connected, the voltage variation range of the DC bus, that is, the charging and discharging voltage range of the lithium-ion battery pack matches the working voltage range of the electric bicycle moto...

AI Technical Summary

Problems solved by technology

[0004] However, the above-mentioned energy management system controller after considering the cost of the fuel cell system controller and its auxiliary peripherals is relatively complex, the controller occupies a large space, has poor flexibility, and will greatly increase the parasitic power consumption of the system. Moreover, the integration cost of the system controller accounts for a relatively large proportion of the system construction cost, which can reach more than 20%, which seriously restricts the commercialization of fuel cell / lithium battery hybrid electric bicycles. Effectively balance system control performance, power consumption and vehicle cost

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