High-frequency inverter ripple

Does current ripple affect battery performance?

This paper documents an experimental investigation that studies the long-term impact of current ripple on battery performance degradation. Initial results highlight that both capacity fade and impedance rise progressively increase as the frequency of the superimposed AC current increases.

What causes high frequency AC ripple on a DC link?

Another source of high frequency AC ripple on the DC link, is from the electrical machine employed for vehicle propulsion. The machine produces odd harmonics arising from the non-sinusoidal back-EMF (electromagnetic force) waveform.

What is a single-phase full bridge inverter?

Single-phase full bridge inverter gives high efficiency and high-reliability characteristics. However, it needs a large DC link capacitor to absorb the ripples through it i.e. high frequency voltage/current ripple and low frequency 2ω ripple. The SPWM for a single-phase full bridge inverter can be divided into bipolar and unipolar modulations.

How does current ripple affect resistance?

By comparing the EIS results presented in Fig. 8, Fig. 9, it can be seen that cells cycled with a current ripple at 14.8 kHz, experience a relatively rapid rise in R t (circa: 0.02 Ohms) between 0 and 600 cycles; the rate of rise of resistance (R t) for the same cells then reduces considerably between 600 and 1200 cycles.

How stable is ripple amplitude & frequency?

The ripple amplitude and frequency present on the cell when measured at intervals over the period of the test, was stable to within the ±1% of amplitude and 10 −6 % of frequency.

How to analyze the output current ripple?

To analyze the output current ripple, firstly the mean square value of the current ripple during the switching period is formulated. After that, the mean square value during a fundamental period is calculated. The switching period is determined by the frequency of the carrier signal and the fundamental period by the reference signal.