An isolating two-way constant-current maintenance system based on a power supply of shared equipment, used for maintaining battery packs consisting of battery cells, the system comprising a power supply, an electronic switch K1, a current sensor, a main battery management system controller, and a plurality of secondary battery management system controllers, wherein the power supply is connected with the current sensor;
- the current sensor is respectively connected with the electronic switch K1 and the main battery management system controller;
- the electronic switch is respectively connected with the main battery management system controller and the secondary battery management system controllers;
- the main battery management system controller is respectively in a communication connection with the plurality of secondary battery management system controllers;
- each one of the secondary battery management system controllers is connected with a battery pack;
- wherein each one of the secondary battery management system controllers comprises a maintenance circuit, a battery cell acquisition circuit and a secondary MCU (Micro-programmed Control Unit);
- the secondary MCU is respectively connected with the maintenance circuit and the battery cell acquisition circuit;
- wherein the main battery management system controller comprises a battery pack acquisition circuit and a main MCU;
- the main MCU is connected with the battery pack acquisition circuit;
- the battery pack acquisition circuit is connected with two ends of the battery pack;
- wherein the maintenance circuit comprises a PWM (Pulse-Width Modulation) controller, a filter capacitor LL1, a field effect tube Q1, a transformer T, a field effect tube Q2, a filter capacitor LL2, a gating switch K, a signal switching circuit, a drive circuit, and a voltage-current acquisition and feedback circuit;
- two terminals, a, b, of a main coil of the transformer T are respectively connected with one end of the filter capacitor LL1 and a drain electrode of the field effect tube Q1;
- a source electrode of the field effect tube Q1 is connected with the other end of the filter capacitor LL1 and is grounded;
- two terminals, c, d, of a secondary coil of the transformer T are respectively connected with one end of the filter capacitor LL2 and a drain electrode of the field effect tube Q2;
- a source electrode of the field effect tube Q2 is connected with the other end of the filter capacitor LL2 and the voltage-current acquisition and feedback circuit;
- grid electrodes of the field effect tube Q1 and the field effect tube Q2 are respectively connected with the drive circuit;
- the terminal a of the main coil and the terminal c of the secondary coil of the transformer T are respectively connected with the voltage-current acquisition and feedback circuit;
- the two ends of the filter capacitor LL1 are respectively connected with an anode and a cathode of the power supply;
- the PWM controller is respectively connected with the voltage-current acquisition and feedback circuit, the signal switching circuit and the power supply;
- the signal switching circuit is connected with the drive circuit;
- the voltage-current acquisition and feedback circuit is connected with the gating switch;
- the gating switch is connected with a tested battery pack.
- wherein the gating switch comprises a plurality of anode switches K4 and cathode switches K5 which correspond to the battery cells one by one;
- each one of the anode switches K4 has one end connected to the voltage-current acquisition and feedback circuit and the other end connected to the anode of the corresponding one of the battery cells;
- and each one of the cathode switches K5 has one end connected to the voltage-current acquisition and feedback circuit and the other end connected to the cathode of the corresponding one of the battery cells.