Method for determining adhesion failure of output contactor of direct-current charging pile

Abstract

The invention relates to a method for determining an adhesion failure of an output contactor of a direct-current charging pile. Three states including a state before charging, a charging state, and astate after charging are provided. According to the determination method, different processing steps are provided for the three kinds of states. Before charging, the following steps are performed: a charging pile is started for charging, a direct-current output contactor is disconnected, and a battery loop voltage value of an electrical vehicle is determined; if the battery has no voltage, startupis carried out and a charging module is started, and the voltage of the charging module boosts to be a designated voltage; the battery voltage value is determined, if the battery voltage is equal toa module voltage, the output contactor is closed in an adhesion state; if the battery has no voltage, contact state normality information is outputted and a next-step detection is carried out; the output contactor is closed, the battery voltage value is determined again, if the battery has no voltage, the output contact is closed in an adhesion state; and if the battery voltage is equal to the module voltage, the output contactor state is normal and next-step insulation detection and charging are carried out. According to the invention, a set of complete detection methods is provided for threedifferent states including the state before charging, the charging state, and the state after charging, so that an adhesion failure state of the output contact is determined.

Description

technical field [0001] The invention relates to the field of electric vehicle charging, in particular to a method for judging a sticking fault of an output contactor of a DC charging pile. Background technique [0002] Due to the material and life of the DC output contactor of the charging pile, there is a risk of the contactor sticking when closing and opening. When the contactor is closed and sticking, the output contactor is always in the closed state, and the charging gun head of the charging pile is charged. , There is a danger of personal safety in engineering applications; when the contactor is in the open state, the output contactor is always in a disconnected state, and the charging pile cannot charge the electric vehicle, resulting in a waste of resources. [0003] In order to solve the above problems, most of the industry use output contactors with feedback nodes. The principle is that this type of contactor will feedback the current opening and closing status of ...

AI Technical Summary

Problems solved by technology

[0002] Due to the material and life of the DC output contactor of the charging pile, there is a risk of the contactor closing and opening adhesion. When the contactor is closed and stuck, the output contactor is always closed, and the charging gun head of the charging pile is charged. , there is a danger to personal safety in engineering applications; when the contactor is open and stuck, the output contactor is always disconnected, and the charging pile cannot charge the electric vehicle, resulting in a waste of resources

[0003] In order to solve the above problems, most of the industry uses output contactors with feedback nodes. The principle is that this type of contactor will feedback the current opening and closing status of the contactor to determine whether the contactor is abnormal, but the premise is that the signal of the feedback node Correct, there is still a risk of misjudgment if the feedback signal fails

At the same time, when the selection parameters are the same, the cost of the output contactor with feedback node is much higher than that of the output contactor without feedback node, and there are much fewer contactor suppliers. How to use the output contactor without feedback node can be correct Reliable judgment of contactor sticking faults has been puzzling the development of the industry

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