Vacuum boosting system, electric vehicle and vacuum boosting control method

Abstract

The invention disclose a vacuum boosting system, which comprises a vacuum booster (1), a vacuum degree sensor (2), an electric vacuum pump (3), a control unit (4) and a vacuum tank (10), wherein the vacuum degree sensor (2) is arranged on the vacuum booster (1), and is used for acquiring the vacuum degree in the vacuum booster (1); the control unit (4) is electrically connected with the vacuum degree sensor (2) and the electric vacuum pump (3) respectively; the electric vacuum pump (3) is connected with the vacuum booster (1) and the vacuum tank (1) through pipelines respectively; the vacuum tank (10) is communicated with the vacuum booster (1). Moreover, the invention further provides an electric vehicle comprising the vacuum boosting system, and a corresponding vacuum boosting control method. By adopting the vacuum boosting system, the electric vacuum pump can be prevented from being started frequently, and the service life of the electrically-controlled vacuum pump is prolonged remarkably.

Description

technical field [0001] The invention relates to the field of automobile braking, in particular to a vacuum booster system. In addition, the present invention also relates to an electric vehicle comprising the above-mentioned vacuum assist system. Further, the present invention also relates to a vacuum booster control method. Background technique [0002] For electric vehicles using hydraulic brakes, a vacuum booster is generally used in the hydraulic brake system to increase the pressure of the pipeline to obtain the required braking force. The vacuum booster needs vacuum as an energy source, so the vacuum pump in the vacuum booster system sucks the gas in the vacuum booster when it works, so as to keep the vacuum degree of the vacuum used in the braking system within a safe range to ensure the vehicle driving safety. When the vacuum degree is lower than the lower limit of the safety range, the effect of the vacuum booster will be significantly reduced, which will cause s...

AI Technical Summary

Problems solved by technology

[0004] However, the batteries used in electric vehicles currently have low energy consumption. If the electric vacuum pump on the electric vehicle continuously pumps vacuum like the mechanical vacuum pump connected to the fuel engine, it will cause unnecessary waste of energy

[0005] In addition, the brake system usually requires a safe range of vacuum degree of 50bar to 80bar. Therefore, every time a safety brake is performed (stepping on the brake), the electric vacuum pump works once. If the electric vacuum pump does not work at this time, then the second safety brake After that, the vacuum degree in the vacuum booster will quickly drop to the lower limit of the safe range, thus greatly reducing the safety of electric vehicles

In addition, in view of the fact that electric vehicles are mostly used in urban traffic and sanitation, the number of braking is relatively frequent, so the electric vacuum pump will be started frequently, and the service life of the electric vacuum pump will be significantly reduced

In particular, when an electric vehicle brakes on a road that goes down a long slope continuously, the electric vacuum pump will always work, causing the temperature of the electric vacuum pump to be too high, which seriously affects its service life

Therefore, the application of this control method is greatly limited

Furthermore, since the vacuum booster of the large-tonnage hydraulic brake vehicle consumes more vacuum every time it works, this control method cannot meet the requirements of the large-tonnage hydraulic brake vehicle.

Therefore, this control method is only applied to N1 or M1 vehicles with light load.

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