Abstract: The present invention relates to a method for measuring the AC impedance of a battery in a composite power supply power system, comprising the following steps: determining the AC disturbance signal amplitude, operating the DC/DC voltage converter to generate the AC disturbance signal, collecting the output signals of the fuel cell and the lithium battery, calculating the output power of the fuel cell and the lithium battery; calculating the demand power of the load, and when the demand power is stable, calculating the impedance of the lithium battery and the fuel cell separately, otherwise, only the impedance of the fuel cell is calculated.

Abstract: An online impedance spectrum measuring device and method for a vehicle-mounted hydrogen fuel cell includes: a controllable alternating current source, configured to apply a sinusoidal alternating signal; a cell voltage signal preceding-stage measuring circuit, configured to select to communicate with one monocell via a voltage signal gating circuit; a current sensor and a cell current signal preceding-stage measuring circuit connected with the current sensor; and a signal conditioning and amplifying circuit, a multi-channel simultaneous sampling analog-digital conversion circuit, a digital signal processor and an upper computer, which are connected in sequence, wherein the signal conditioning and amplifying circuit is connected to the cell voltage signal preceding-stage measuring circuit and the cell current signal preceding-stage measuring circuit, separately; and the upper computer is connected with the controllable alternating source and the voltage signal gating circuit.

Abstract: The present invention relates to a method for measuring the AC impedance of a battery in a composite power supply power system, comprising the following steps: determining the AC disturbance signal amplitude, operating the DC/DC voltage converter to generate the AC disturbance signal, collecting the output signals of the fuel cell and the lithium battery, calculating the output power of the fuel cell and the lithium battery; calculating the demand power of the load, and when the demand power is stable, calculating the impedance of the lithium battery and the fuel cell separately, otherwise, only the impedance of the fuel cell is calculated.

Abstract: An online impedance spectrum measuring device and method for a vehicle-mounted hydrogen fuel cell includes: a controllable alternating current source, configured to apply a sinusoidal alternating signal; a cell voltage signal preceding-stage measuring circuit, configured to select to communicate with one monocell via a voltage signal gating circuit; a current sensor and a cell current signal preceding-stage measuring circuit connected with the current sensor; and a signal conditioning and amplifying circuit, a multi-channel simultaneous sampling analog-digital conversion circuit, a digital signal processor and an upper computer, which are connected in sequence, wherein the signal conditioning and amplifying circuit is connected to the cell voltage signal preceding-stage measuring circuit and the cell current signal preceding-stage measuring circuit, separately; and the upper computer is connected with the controllable alternating source and the voltage signal gating circuit.