Insulation detection module, power battery insulation detection device and method and vehicle

Abstract

The invention discloses an insulation detection module, a power battery insulation detection device and method and a vehicle. The insulation detection module comprises a capacitor C1, a capacitor C2,resistors R4 to R7, a resistor r1, a resistor r2, an inductor L, switches K1 to K6, a diode D1 and a diode D2. One end of the capacitor C1 is grounded, the other end of the capacitor C1 passes throughthe resistor R5, the resistor r2, the resistor R4, the capacitor C2 and the switch K6 in sequence and then is grounded, and the connection point of the resistor r2 and the resistor R4 is grounded. One end of the resistor R7 is connected with a connection point of the resistor R5 and the capacitor C1, and the other end of the resistor R7 is connected with a connection point of the resistor R4 andthe capacitor C2 after sequentially passing through the switch K3, the switch K2 and the resistor R6. The connection point of the switch K2 and the switch K3 is connected with one end of the inductorL through the switch K5, and the connection point of the switch K2 and the switch K3 is further connected with the other end of the inductor L through the battery E, the switch K4 and the resistor r1in sequence. According to the invention, the precision of calculating the insulation resistance value is improved.

Description

technical field [0001] The invention belongs to the technical field of automobile hardware circuits and control methods, and in particular relates to an insulation detection module, a power battery insulation detection device, a method and a vehicle. Background technique [0002] The power battery is one of the core components of new energy vehicles. Since the power battery has a DC high-voltage output, if the positive and negative insulation of the high-voltage circuit is damaged and the vehicle ground (low-voltage power supply ground) is falsely connected, it may cause the risk of electric shock and high-voltage short circuit to the occupants. Insulation detection It is an important part of power battery safety considerations. At present, the more economical and direct insulation detection method is to connect different resistors in parallel to the positive and negative poles of the battery and the vehicle ground, and calculate the insulation resistance value based on the ...

AI Technical Summary

Problems solved by technology

However, due to the existence of X capacitors and Y capacitors on the whole vehicle, the voltage division value of the resistance cannot be stabilized in a short period of time. Therefore, it takes a few seconds or even longer to use the resistance voltage division method to detect the detection result of the insulation resistance. , thereby reducing the significance of insulation detection

[0003] Another example is a high-voltage insulation monitoring circuit and monitoring method for electric vehicles disclosed in the patent document CN 201310676894.1, in which the insulation inspection circuit uses a capacitor charging and discharging method to calculate the insulation resistance, but the device can only work in the high-voltage activation state, and Even if it can work in the state of high-voltage inactivation, due to the high-voltage characteristics of the power battery, the series resistance must be high-impedance, and the capacitance voltage change will be very small under the low-voltage state, which puts a high limit on the range or accuracy of voltage detection. requirements

Images