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Why calculate 22kv in mva?
A kilovolt (kV, not 'kv') is the SI unit for potential and potential difference (voltage), whereas the kilovolt ampere (kV.A, not'kva') is the unit for apparent power. These are quite different quantities, so you cannot change one to another -if that is what you are asking.
Why 22kv 11kv 33kv 132kv 220 kv are standard transmission voltages in transmission lines why not 20kv 10kv etc?
Its just a matter of standard. In my area, for instance, we use 13.2 KV for distribution lines, and 69 KV / 138 KV for transmission lines.
What does a primary substation do?
Primary substation - when the transformer is HV/MV or MV/MV. e.g. substation designed for 132kV/33kV or 230kV/22kV or 33kV/11kV etc stepped down for MV distribution (mainly for utilities and heacy industries) Secondary substation - when the transformer is HV/LV or MV/LV. e.g. substation designed for 11kV/400V or 6.6kV/400V etc stepped down for LV distribution (mainly for residential, commercial) sometime referred to as a kiosk substation.
How do you calculate knee point voltage?
Step 1: calculating knee point voltage Vkp Vkp = {2 x Ift (Rct+Rw)}/ k Vkp = required CT knee point voltage Ift = max transformer through fault in ampere Rct = CT secondary winding resistance in ohms Rw = loop impedance of pilot wire between CT and the K = CT transformation ratio Step 2: calculate Transformer through fault Ift Ift = (KVA x 1000)/(1.732 x V x Impedance) KVA = transformer rating in kVA V = transformer secondary voltage Impedance = transformer impedance Step 3: How to obtain Rct To measure when CT is produce Step 4: How to obtain Rw This is the resistance of the pilot wire used to connect the 5th class X CT at the transformer star point to the relay in the LV switchboard. Please obtain this data from the Electrical contractor or consultant. We provide a table to serve as a general guide on cable resistance. Example: Transformer Capacity : 2500kVA Transformer impedance : 6% Voltage system : 22kV / 415V 3phase 4 wire Current transformer ratio : 4000/5A Current transformer type : Class X PR10 Current transformer Vkp : 185V Current transformer Rct : 1.02½ (measured) Pilot wire resistance Rw : 25 meters using 6.0mm sq cable = 2 x 25 x 0.0032 = 0.16½ Ift = (kVA x 1000) / (1.732 x V x impedance) = (2500 x 1000) / (1.732 x 415 x 0.06) = 57,968 round up 58,000A Vkp = {2 x Ift (Rct+Rw) } / k = {2 x 58000 (1.02+0.16) } / 800 = 171.1½
Does 22kv generator exits in India?
yES IT IS Using in NTPC India.
Why normally Generator rating are between 11Kv to 22Kv?
Because if we use a generator of 33kv or higher then the radii must be of 2-3 meters that is not good. And also the area of the generator will be very high and losses and heat paameters will also be high. The main point is that we use 11kv generator at power plants and we have to step up the power to 220KV or 500KV etc. So we use 11kv or 22kv instead of 33 kv or higher.. By doing so we save the cost of area required, radii of rotor, and losses produced by higher power generators.
Why calculate 22kv in mva?
A kilovolt (kV, not 'kv') is the SI unit for potential and potential difference (voltage), whereas the kilovolt ampere (kV.A, not'kva') is the unit for apparent power. These are quite different quantities, so you cannot change one to another -if that is what you are asking.
Why 22kv 11kv 33kv 132kv 220 kv are standard transmission voltages in transmission lines why not 20kv 10kv etc?
Its just a matter of standard. In my area, for instance, we use 13.2 KV for distribution lines, and 69 KV / 138 KV for transmission lines.
What does a primary substation do?
Primary substation - when the transformer is HV/MV or MV/MV. e.g. substation designed for 132kV/33kV or 230kV/22kV or 33kV/11kV etc stepped down for MV distribution (mainly for utilities and heacy industries) Secondary substation - when the transformer is HV/LV or MV/LV. e.g. substation designed for 11kV/400V or 6.6kV/400V etc stepped down for LV distribution (mainly for residential, commercial) sometime referred to as a kiosk substation.
What voltage does New Zealand use?
New Zealand uses 230 V @ 50 Hz, the same as the UK and Australia. Wall power outlets are the same as Australia - two flat live and neutral blades in an inverted-V shape, with a single vertical flat earth pin below New Zealand's mains supply is incompatible with appliances designed for the US and Canada (120 V @ 60 Hz) - so do not attempt to put a US appliance in a NZ socket by bending the pins. High voltage lines are usually at 230/400 V, 6.6kV, 11kV, 22kV (local distribution), 33kV, 50kV, 66kV (sub-transmission), 110kV, 220kV (transmission) and +/-350kV HVDC (the inter-island link connecting the North and South Islands across Cook Strait)
How do you calculate knee point voltage?
Step 1: calculating knee point voltage Vkp Vkp = {2 x Ift (Rct+Rw)}/ k Vkp = required CT knee point voltage Ift = max transformer through fault in ampere Rct = CT secondary winding resistance in ohms Rw = loop impedance of pilot wire between CT and the K = CT transformation ratio Step 2: calculate Transformer through fault Ift Ift = (KVA x 1000)/(1.732 x V x Impedance) KVA = transformer rating in kVA V = transformer secondary voltage Impedance = transformer impedance Step 3: How to obtain Rct To measure when CT is produce Step 4: How to obtain Rw This is the resistance of the pilot wire used to connect the 5th class X CT at the transformer star point to the relay in the LV switchboard. Please obtain this data from the Electrical contractor or consultant. We provide a table to serve as a general guide on cable resistance. Example: Transformer Capacity : 2500kVA Transformer impedance : 6% Voltage system : 22kV / 415V 3phase 4 wire Current transformer ratio : 4000/5A Current transformer type : Class X PR10 Current transformer Vkp : 185V Current transformer Rct : 1.02½ (measured) Pilot wire resistance Rw : 25 meters using 6.0mm sq cable = 2 x 25 x 0.0032 = 0.16½ Ift = (kVA x 1000) / (1.732 x V x impedance) = (2500 x 1000) / (1.732 x 415 x 0.06) = 57,968 round up 58,000A Vkp = {2 x Ift (Rct+Rw) } / k = {2 x 58000 (1.02+0.16) } / 800 = 171.1½
