Voltage is the potential difference between two points in a closed circuit. Voltage can be compared to the difference in water pressure.
The difference in water pressure causes the water to flow up and down, and the voltage causes current to flow from the positive electrode to the negative electrode.
When multiple impellers (similar to the impellers of a hydraulic generator) are connected in series to a closed waterway, each impeller will reduce some of the water pressure, so that the difference pressure of the entire waterway will be distributed to everyone. turbine. The circuit is similar, the wheel is like the resistance of the circuit.
When the wheels are connected to the waterway in parallel, the water pressure difference of each wheel is the same. In the parallel circuit the situation is also the same.
I want to be more detailed, but I'm afraid you'll find it wordy. hehe!
In the hy turbinesdroelectrics, water flow can only flow in and out in two directions, unlike wind, which must change in 360-degree directions. Therefore, when the water flow changes in the forward and reverse direction, there is no need to change the direction of the impeller. You just need to adjust the phase order of the three-phase generator. Of course, if the water height is different, variable frequency electricity production can also be considered.
If the hydraulic turbine does not have a flow channel and can accommodate water flow in any direction, it can only be a vertical axis hydraulic wheel. Of course, we're just talking. This type of tidal power generation has no real commercial value. What's really available now is to block tidal energy in the bay.