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Hello all,

In my country (the Netherlands) we nowadays are having a system where you can supply PV-power to the grid and take power from the grid for the same rates (it is called : "salderingsregeling").
However this system will come to an end in a few years.
From then on, you will be paying about € 0,20/kWh for what you will be using from the grid and you will be getting payed around € 0,06 for power you are supplying to the grid.
So it is becoming more important to use a maximum of the produced solar power directly (so whithout using the grid as temporary "storage").
We have a net zero energy house. See: https://geen-energierekening-meer.weebly.com/ (in Dutch).
This is including heat pump for heating and DHW and the consumption of two electric cars, being a BMW-i3 and VW-E-Up.

I want to build a power management system by means of a PLC, with following inputs:
• consumed power i3
• consumed power E-up
• consumed power rest of the house (appliances, heat-pump, lighting, etc.)
• produced PV-power
and an output (0-10V) to be used for
• controlling the charging power of the cars (only one car is (nowadays)/ will (in the future) being charged at the same time)
So for this I will need a charger from which the charging power can be controlled by means of a 0-10V input signal.
The chargers that we are using now have a maximum power of 2.3 kW (10 Amps at 230 V). Which is fine for us.
Does anyone know of a charger that I could build, using this 0-10V input signal for powercontrol?
 

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That's an interesting change in metering and billing. I'm not surprised, and I don't think anyone should be.

I want to build a power management system by means of a PLC, with following inputs:
• consumed power i3
• consumed power E-up
• consumed power rest of the house (appliances, heat-pump, lighting, etc.)
• produced PV-power
and an output (0-10V) to be used for
• controlling the charging power of the cars (only one car is (nowadays)/ will (in the future) being charged at the same time)
So for this I will need a charger from which the charging power can be controlled by means of a 0-10V input signal.
The chargers that we are using now have a maximum power of 2.3 kW (10 Amps at 230 V). Which is fine for us.
Does anyone know of a charger that I could build, using this 0-10V input signal for powercontrol?
All of that makes a lot of sense, except for the 0-10V signal requirement. I understand that's what you can readily produce from an analog output port of the PLC, but it is a technically obsolete approach; industrial applications started replacing this sort of analog signal with digital communications (typically some sort of FieldBus) decades ago. Are you open to the possibility of CAN (Controller Area Network) or another form of digital communications?
 

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...
and an output (0-10V) to be used for
• controlling the charging power of the cars (only one car is (nowadays)/ will (in the future) being charged at the same time)
So for this I will need a charger from which the charging power can be controlled by means of a 0-10V input signal.
The chargers that we are using now have a maximum power of 2.3 kW (10 Amps at 230 V). Which is fine for us.
Does anyone know of a charger that I could build, using this 0-10V input signal for powercontrol?
Will you be using a J1772 type charging port/protocol--is that a requirement of your system, i.e. a pilot signal to indicate maximum current available and a proximity circuit for connection and release of the charging handle, or some other protocol? i think 6 Amps is the lowest setting for the max input current level according to the 1772 protocol.

The Mains AC typically plugs in to an EVSE, which signals to the on-board charger thru the J1772 handle the maximum AC current available using the duty cycle of a PWM pilot signal. The EVSE is basically a pass-thru device but is limited by the ratings of the internal components and the supply line. But the on-board charger controls itself based upon the expected supply current. If you tell it you only have 6 amps available, then it will regulate and supply HVDC out to the battery pack at that input level.

So what do you want to control with the 0-10 analog--the EVSE limits on max AC supply available, or the on-board charger output current?
 

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The Mains AC typically plugs in to an EVSE, which signals to the on-board charger thru the J1772 handle the maximum AC current available using the duty cycle of a PWM pilot signal. The EVSE is basically a pass-thru device but is limited by the ratings of the internal components and the supply line. But the on-board charger controls itself based upon the expected supply current. If you tell it you only have 6 amps available, then it will regulate and supply HVDC out to the battery pack at that input level.
I think this is a promising approach - convert the 0-10V analog to a PWM signal for the EVSE, and let a readily available on-board charger use the established protocol to respond to it. It doesn't matter why you are limiting the current, only that the car's charger follows the command.

Range of control seems to be the only issue, since the system must (presumably) operate at 230 volts (no lower-power 120V option as in North America), and so the available range might be only 6 to 10 amps (1.4 to 2.3 kW). Perhaps someone knows if some chargers continue to proportion current below 6 amps with a PWM signal under 10%.
 

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Hello all,

In my country (the Netherlands) we nowadays are having a system where you can supply PV-power to the grid and take power from the grid for the same rates (it is called : "salderingsregeling").
However this system will come to an end in a few years.
From then on, you will be paying about € 0,20/kWh for what you will be using from the grid and you will be getting payed around € 0,06 for power you are supplying to the grid.
So it is becoming more important to use a maximum of the produced solar power directly (so whithout using the grid as temporary "storage").
We have a net zero energy house. See: https://geen-energierekening-meer.weebly.com/ (in Dutch).
This is including heat pump for heating and DHW and the consumption of two electric cars, being a BMW-i3 and VW-E-Up.

I want to build a power management system by means of a PLC, with following inputs:
• consumed power i3
• consumed power E-up
• consumed power rest of the house (appliances, heat-pump, lighting, etc.)
• produced PV-power
and an output (0-10V) to be used for
• controlling the charging power of the cars (only one car is (nowadays)/ will (in the future) being charged at the same time)
So for this I will need a charger from which the charging power can be controlled by means of a 0-10V input signal.
The chargers that we are using now have a maximum power of 2.3 kW (10 Amps at 230 V). Which is fine for us.
Does anyone know of a charger that I could build, using this 0-10V input signal for powercontrol?

Hi Zwerius,

You have a nice inquiry as I was supposed to know the same thing. I had to deal with the high payed electricity to charge my car and other some electrical equipment. I got a final solution by visiting many websites like Walmart, Magesolar, Amazon and much more.

Try this method to get perfect knowledge on this and know permanent solution.

Thank you. :):)
 
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