A new measurement technology of synchronous sampling based on flying capacitor

As battery module voltage measurement on power battery pack not only has to overcome hundreds of common mode voltage, but also needs to measure synchronously multi-battery module voltage signal, in the thought of synchronous sampling and time-measurement, develops a new type of flying capacitor synchronous sampling measurement which has the function of electrical isolation and can measure simultaneously several module battery voltage signal. The measurement circuit is mainly composed of synchronous sampling relay group, the same number of AD convert sampling relay and sampling keep capacitor. Software and hardware implementations of the technology, compensation and calibration methods of differences are put forward, which achieve the isolation and measurement function of multi-battery module voltage signal by adopting the C8051F040 digital simulation synthetic microprocessor. Experimental results indicate that the performance and specifications of power battery management system have greatly improved with the technology.