Multipoint electric automobile insulation test system and detection method thereof

The invention discloses a multipoint electric automobile insulation test system and a detection method thereof. A test system circuit comprises a power battery, a battery voltage sampling circuit, a multichannel voltage switching circuit and isolation amplifier unit, a voltage measuring and controller unit, a multi-monitoring-point switching circuit and an equivalent insulation resistor set for k monitoring points of anode and cathode pairs of a power battery, wherein k is an positive integer larger than or equal to one. The detection method comprises three steps, and the insulation condition of all detection points and the power battery can be acquired respectively through detection and calculation. The multipoint electric automobile insulation test system is simple in circuit and low in cost, and under the AD condition that 12 or more bits are selected, the measuring precision is better than 2.5%. The switching path numbers of monitoring points only need to be increased, the insulation condition of the powe