A method for controlling a range extender

Abstract

The invention discloses a novel control method for a range extender; range extender engine speed is adjusted according to a current signal, generating power of the range extender is matched with consuming power of a load motor, energy is delivered directly between power generation of the range extender and power consumption of the load motor, energy conversion loss and battery pack damage due to the charging of a battery pack by the range extender are avoided; when the load motor has no electricity consumption, an engine is tuned to run at idle speed, the range extender outputs with no power, and oil consumption and noise are minimized. The battery pack is protected, and the service life of the range extender is prolonged.

Description

technical field [0001] The invention relates to a range extender for electric vehicles, in particular to a control method for the range extender, which belongs to the technical field of new energy electric vehicles. Background technique [0002] With the rapid development of the new energy electric vehicle industry, the consumer market for electric vehicles is increasing year by year, and consumers have increasing expectations for the mileage of electric vehicles. However, the current battery technology has always been the main factor restricting the mileage of electric vehicles. The emergence of the remote controller has alleviated the problem of the cruising range of electric vehicles. [0003] There are two main power generation control methods for the range extender at present: one is to adjust the engine speed according to the difference between the set voltage value and the battery pack voltage value to achieve a constant voltage output and provide a stable power suppl...

AI Technical Summary

Problems solved by technology

[0004] Disadvantages of the first control method: 1. When the voltage of the battery pack is lower than the set voltage value, the range extender will charge the battery pack. If the voltage difference between the two is large, excessive current charging will occur. 2. The charging of the battery pack by the range extender is converted from electrical energy to chemical energy, and the discharge of the battery pack is converted from chemical energy into electrical energy, which increases twice Energy conversion will inevitably make the final energy conversion efficiency of the range extender low; 3. Regardless of whether the load motor consumes electricity or not, the engine of the range extender is always running at high speed, resulting in shortened service life of the engine, low efficiency, and loud noise

[0005] Disadvantages of the second control system: the precise matching between the generating power of the range extender and the power of the load motor cannot be realized

When the accelerator pedal is stepped on, the range extender will also output higher power. When the load motor load is small and the power generated by the range extender cannot be fully consumed, it will cause high current charging and overvoltage of the battery pack, such as , which occurs when the vehicle goes downhill

When the accelerator pedal is depressed slightly and the load motor is in a heavy load state, the generated power of the range extender cannot meet the power consumption requirements of the load motor, resulting in over-discharge of the battery pack.

[0006] When the engine is running in the two control modes, the speed is high and the noise is loud, the generator will charge the battery pack uncontrollably, and in the process of oil-to-electric conversion, both control modes also have the charging of the battery pack by the range extender Phenomenon, the process from the range extender to the battery pack to the load motor, the three conversions greatly reduce the energy conversion efficiency of electric vehicles and increase unnecessary energy loss

[0007] In summary, the existing technology obviously has defects in actual use

Images