Architecture of a battery and control device
A battery system comprises a battery module, including a high-voltage grid and a low-voltage network having a BCU. The battery module includes a plurality of battery cells connected in series and a plurality of cell monitoring units configured to measure and to transmit battery voltages of the battery cells with respect to a first control signal. The BCU is configured to determine a charge state of the battery cells. The BCU includes a microcontroller and a nanocontroller. The nanocontroller is or can be directly connected to the cell monitoring units and is connected to the microcontroller by means of an isolator, and is configured to generate the first control signal and to transmit the signal to the cell monitoring units and to receive the battery voltages of the battery cells transmitted by the cell monitoring units and relay same to the microcontroller.
1. A battery system comprising:
a high voltage network including a battery module , the battery module having a plurality of battery cells connected in series and a plurality of cell monitoring units configured to measure battery voltages of the battery cells in response to a first control signal; and
a low voltage network including a BCU, the BCU configured to determine a state of charge of the battery cells and the BCU having:
a microcontroller; and
a nanocontroller directly connected to the plurality of cell monitoring units and operatively connected to the microcontroller via an isolator and configured to:
generate the first control signal,
transmit the first control signal to the cell monitoring units,
receive the battery voltages of the battery cells from the cell monitoring units, and
provide the battery voltages to the microcontroller.
2. The battery system as claimed in claim 1 , wherein the nanocontroller is connected to the microcontroller via the isolator by means of a CAN bus.
3. The battery system as claimed in claim 1 , wherein:
the nanocontroller is connected to a first current sensor, the first current sensor is configured to measure a current through the battery module in response to a second control signal and the nanocontroller is further configured to generate the second control signal and to transmit the current measurement result to the nanocontroller.
4. The battery system as claimed in claim 3 , wherein the nanocontroller is further configured to generate the first and the second control signals synchronously.
5. The battery system as claimed in claim 3 , wherein the first current sensor is a shunt resistor having an evaluation unit connected downstream.
6. The battery system as claimed in claim 1 , wherein the nanocontroller is further configured to determine the state of charge of the battery cells.
7. The battery system as claimed in claim 1 , wherein the nanocontroller is further configured to compare the battery voltages with a predefined limiting value and to generate a first alarm signal if the battery voltages exceed the predefined limiting value.
8. The battery system as claimed in claim 1 , wherein the nanocontroller is further configured to transmit monitoring messages to the microcontroller at regular intervals and to receive a response from the microcontroller.
9. The battery system as claimed in claim 8 , wherein the nanocontroller is further configured to generate a second alarm signal if the nanocontroller does not receive the response from the microcontroller.
10. The battery system as claimed in claim 8 , wherein the microcontroller is further configured to generate a second alarm signal if the microcontroller does not receive the response from the nanocontroller.
11. The battery system as claimed in claim 1 , wherein the microcontroller is connected to a second current sensor configured to measure a current through the battery module in response to a third control signal, and to transmit the current measurement result to the microcontroller.
12. The battery system as claimed in claim 11 , further comprising:
a first main contactor, operatively connected between a first pole of the battery cells and a first output of the battery module, the first main contractor includes a first control input operatively connected to the nanocontroller; and
a second main contactor, operatively connected between a second pole of the battery cells and a second output of the battery module, the second main contractor includes a second control input operatively connected to the microcontroller,
the nanocontroller and the microcontroller are configured to control opening and closing of at least one of the first and second main contactor.
13. The battery system as claimed in claim 12 , wherein:
the nanocontroller is operatively connected to the second control input of the second main contactor,
the microcontroller is operatively connected to the first control input of the first main contactor, and
at least one of the nanocontroller and the microcontroller further configured to open at least one of the second main contactor and the first main contactor if at least one of the microcontroller and the nanocontroller fail.
14. The battery system as claimed in claim 11 , wherein the second current sensor is a Hall sensor.
15. The battery system as claimed in claim 1 , wherein the microcontroller is configured to transmit monitoring messages to the nanocontroller at regular intervals and to receive a response from the nanocontroller.