Hi Community,
I have modelled a grid using a programmable three phase voltage source and there are three loads attached to it. Model & Parameter file is attached. Each load is defined by the rated active and reactive powers (P& Q) as follows –
Load 1: Rated P = 25 kW; Rated Q = 5 kVA
Load 2: Rated P = 30 kW; rated Q = 10 kVA
Load 3: Rated P = 125 kW; rated Q = 10 kVA
The loads 2 and 3 are switched off at T = 2 secs and switched back on at T = 4 secs. I am also measuring the powers at each of the individual loads as well as the total power supplied by grid.
When I use the voltage source rating = 2300V, the P & Q values are nearly the same (but not exact match) as the above specified parameters.

When I use voltage source = 400V (with everything else remaining the same) there is a huge drop in the measured P & Q values and I am unable to follow why is this happening?

Q1) Why are the measured P&Q so low for V = 400V vs V = 2300V? Is there some limitation on the power this grid can deliver? If yes, then how is this being limited and how can I determine what is the maximum power rating of the load that can be connected across this grid source?
Q2) Additionally in the first scenario with 2300V why are the measured P&Q not the exact match of rated power of loads slightly lesser. I assume some power is lost in "losses" but I canot figure out where are these losses happening?Hi Community,
I have modelled a grid using a programmable three phase voltage source and there are three loads attached to it. Model & Parameter file is attached. Each load is defined by the rated active and reactive powers (P& Q) as follows –
Load 1: Rated P = 25 kW; Rated Q = 5 kVA
Load 2: Rated P = 30 kW; rated Q = 10 kVA
Load 3: Rated P = 125 kW; rated Q = 10 kVA
The loads 2 and 3 are switched off at T = 2 secs and switched back on at T = 4 secs. I am also measuring the powers at each of the individual loads as well as the total power supplied by grid.
When I use the voltage source rating = 2300V, the P & Q values are nearly the same (but not exact match) as the above specified parameters.

When I use voltage source = 400V (with everything else remaining the same) there is a huge drop in the measured P & Q values and I am unable to follow why is this happening?

Q1) Why are the measured P&Q so low for V = 400V vs V = 2300V? Is there some limitation on the power this grid can deliver? If yes, then how is this being limited and how can I determine what is the maximum power rating of the load that can be connected across this grid source?
Q2) Additionally in the first scenario with 2300V why are the measured P&Q not the exact match of rated power of loads slightly lesser. I assume some power is lost in "losses" but I canot figure out where are these losses happening? Hi Community,
I have modelled a grid using a programmable three phase voltage source and there are three loads attached to it. Model & Parameter file is attached. Each load is defined by the rated active and reactive powers (P& Q) as follows –
Load 1: Rated P = 25 kW; Rated Q = 5 kVA
Load 2: Rated P = 30 kW; rated Q = 10 kVA
Load 3: Rated P = 125 kW; rated Q = 10 kVA
The loads 2 and 3 are switched off at T = 2 secs and switched back on at T = 4 secs. I am also measuring the powers at each of the individual loads as well as the total power supplied by grid.
When I use the voltage source rating = 2300V, the P & Q values are nearly the same (but not exact match) as the above specified parameters.

When I use voltage source = 400V (with everything else remaining the same) there is a huge drop in the measured P & Q values and I am unable to follow why is this happening?

Q1) Why are the measured P&Q so low for V = 400V vs V = 2300V? Is there some limitation on the power this grid can deliver? If yes, then how is this being limited and how can I determine what is the maximum power rating of the load that can be connected across this grid source?
Q2) Additionally in the first scenario with 2300V why are the measured P&Q not the exact match of rated power of loads slightly lesser. I assume some power is lost in "losses" but I canot figure out where are these losses happening? grid, programmable voltage source, active power, reactive power, impedance, power measurement MATLAB Answers — New Questions

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