Like many I'm moving towards using the benefits of a grid tie inverter with its MPPT and a low frequency inverter to interface my solar panels to my batteries.
Also like many I want to make sure I don't cook the batteries!!
So far I have 2 x 5kw inverters, each has 2 x 2.5kw trackers in it and my first thought was to switch the DC feed into the inverter to give me 4 charging levels (the value of which depends on the amount of sun at the time). The obvious problem is breaking the 350V DC that is running at up to 8 amps without getting a fireworks display.
My present thought is switching large incandecent lamps in series with the panels to current limit them to regulate the amount coming out of the grid tie, into the LF inverter and hence to the batteries. Something like the 375w heat lights (I'm in a 240v mains country by the way!) but I'm unsure of the panel/inverter characteristics and whether I'll end up with more than the rated voltage across the bulb.
The switching will be less onerous but I've no idea how the whole system will behave.