Current detection system, method and device
The present disclosure provides a current detection system, method and device. The current detection system includes a management unit and a current detection device that is connected with the management unit. The current detection device includes a shunt-type current measurement unit, an open-loop Hall-type current measurement unit and an isolation power unit.
1. A current detection device, comprising:
a shunt-type current measurement unit and a Controller Area Network (CAN) interface;
wherein the shunt-type current measurement unit comprises:
a current sensing device having a shunt resistor, configured to acquire a voltage signal of a power battery pack;
a sampling and signal processing device, configured to calculate a first current value of the power battery pack based on the voltage signal and a resistance value of the shunt resistor; and
an isolation CAN communication unit, configured to electrically isolate the current sensing device having the shunt resistor and the sampling and signal processing device, and transmit the first current value of the power battery pack to the CAN interface via a CAN bus,
wherein the shunt-type current measurement unit further comprises a temperature acquisition unit that includes a thermistor;
the temperature acquisition unit is configured to acquire a resistance value of the thermistor;
the sampling and signal processing device is further configured to obtain a detected temperature value of the current sensing device having the shunt resistor according to the resistance value of the thermistor; and
the isolation CAN communication unit is further configured to transmit the detected temperature value to the CAN interface via the CAN bus.
2. The current detection device of claim 1 , wherein the thermistor is disposed at a near point of the current sensing device having the shunt resistor.
3. The current detection device of claim 1 , wherein the current sensing device having the shunt resistor is a shunt, and the shunt comprises a built-in resistor.
4. The current detection device of claim 3 , wherein the sampling and signal processing device is configured to calculate the first current value of the power battery pack based on a voltage drop across the built-in resistor and a resistance value of the built-in resistor.
5. The current detection device of claim 1 , wherein the CAN interface comprises a CAN high-voltage line interface and a CAN low-voltage line interface.
6. The current detection device of claim 1 , wherein the current detection device further comprises:
an open-loop Hall-type current measurement unit, configured to measure a second current value of the power battery pack with a current sensing device having a magnetic field sensitive element; and
an analog interface, configured to transmit the second current value.
7. The current detection device of claim 6 , wherein the open-loop Hall-type current measurement unit further comprises:
an isolation operational amplifier, configured to electrically isolate the current sensing device having the magnetic field sensitive element, and amplify the second current value;
wherein the analog interface is configured to transmit the second current value amplified.