Replacing the motherboard of a 7KW AC charging station with a 105 ℃ solid-state capacitor would cost an extra 20 yuan - solving half of the problem of speed reduction in summer?

Replacing the 7kW charging pile motherboard with a 105 ℃ solid-state capacitor for 20 yuan can solve half of the problem of speed reduction in summer, limited to the capacitor related half.

What does solid-state capacitor solve

• The traditional liquid electrolytic capacitor has a lifespan of only 2000 hours (about 3 months) at 105 ℃, with high temperature bulging and leakage. After capacity attenuation, ripple loss triggers protection shutdown.

• Solid state capacitors use conductive polymers instead of electrolytes, with a lifespan of over 20000 hours at 105 ℃, a low ESR of 80-90%, minimal ripple heating, and almost no capacity degradation.

• The critical temperature of the capacitor shell dropped from 85 ℃ to the comfort zone of 65 ℃, and the capacitor fault was basically eliminated.

The other half of the problem remains unresolved

• In summer, there are issues such as high temperature oxidation of relay contacts, MCU junction temperature exceeding the threshold, insufficient fan airflow, and voltage drop in the power grid - which are not related to capacitors.

• No matter how heat-resistant the solid-state capacitor is, the relay still adheres at 105 ℃, and the overall thermal environment deteriorates after the fan accumulates dust.

Three traps

• Low ESR causes oscillation: The original design relied on liquid capacitor ESR for damping, but after switching to solid state, high-frequency oscillation may interfere with sampling

• Insufficient withstand voltage margin: Solid state withstand voltage is usually one level lower than liquid state, and matching must be confirmed

• Small capacity density: The solid capacity of the same volume is about 60-70% of the liquid capacity, and the original location may require larger packaging

Is it worth it

• Underground parking lot at 25-30 ℃, liquid capacitors are active for more than 5 years, and solid state replacement is wasteful.

• Ground exposure to 60 ℃+, liquid bulging for half a year, solid stable for 2 years like an old dog, 20 yuan buy operation and maintenance cycle extended from half a year to 2 years, with extremely high ROI.

Conclusion:

Replacing solid-state capacitors only solves half of the summer speed reduction related to capacitors. Relays, heat dissipation, and the other half of the grid voltage need to be comprehensively solved through fan maintenance, thermal pads, and power reduction strategies. 20 yuan is worth it, but it doesn't cure all diseases.

The communication charging pile motherboard produced by Xincheng Technology is of high quality and beautiful price. Welcome to inquire and purchase!