power systems loss

NO-LOAD LOSS IN POWER TRANSFORMER NO LOAD LOSS is the other type of transformer loss which is also known as CORE LOSS. Core loss exists for the reason that transformers of any kind requires electrical currents and magnetic fields that is needed to magnetize the core of the transformer, the sad part is that they are present whenever the transformer is energized whether loaded or unloaded. Unlike the winding loss, core loss requires a constant value regardless of the transformer load; in short, core loss does not vary as transformer load changes. For example, if a power transformer has a core loss of 24kW, 24kW of power must be drawn from the source of supply to cover these losses at all times when the transformer is energized, even if the transformer load side are open.

SUBSTATION TRANSFORMER LOSSES The primary function of a power transformer is to transform system voltage from one nominal level to another. The transformer has to be capable of carrying (within the guidelines of ANSI/IEEE Std. C57.92) the power flow for its particular location in the system under various operating conditions and contingencies, such as line or transformer outages. After we have discussed the contribution of transmission lines and its effects to the level of system’s loss in every utility, we now move to the next part of our discussion which is the Power Transformer. Unlike transmission lines, the functions of power transformer in the system are somewhat more complicated. Power transformers, also known as substation transformers, steps down voltage level received from transmission lines from a higher voltage down to primary distribution levels. This exists in every electric utility due to the fact that most distributors purchase wholesale electricity at transmission vol

SUBSTATION WITH POWER TRANSFORMER A substation in a power system is the one that usually houses the Power transformer. This is also the place where the transformation of voltage occurs. Power transformers found in substations may be either autotransformers or multi-winding conventional transformers. A three-phase installation may consist of a three-phase unit or three single-phase units. The decision as to what type of transformer to purchase depends on such factors as initial installed cost, maintenance costs, operating cost (efficiency), reliability, etc. Three-phase units have lower construction and maintenance costs and can be built to the same efficiency ratings as single-phase units. The initial cost of a three-phase transformer is usually approximately one-third less than four single-phase units. Additionally, the exposure of three-phase units to long outages can be minimized system-wide when a mobile substation or transformer is available for backup in case of failure. RUS Bul

What are the name of the basic parts of a Power Transformer? We can not deny the fact that only a handful of electrical engineering students are presently familiar with power transformers especially on what it looks like. Unlike a transformer we found in our homes, a power transformer’s appearance and construction is somewhat more complicated. It is not just a simple winding with a primary and secondary terminal although basically any transformer has one. The function that a power transformer plays in an electrical system is very important that an electric utility can not afford to loss it during its operation. Our discussion here will focus more on the basic parts and functions of a power transformer that are usually tangible whenever you go to a substation . Although not all power transformers are identical, nonetheless they all have the following listed parts in which the way of construction may differ.

WHAT IS A POWER TRANSFORMER? A power transformer is considered to be a major electrical equipment found in every substation because of its function and since it is the largest, heaviest, and the most expensive device. That is why proper care and protection are done to insure that this device would not be easily damage if faults and overloading will occur. Protective devices like circuit breakers, surge arresters and fuses are usually used to do so.

If your wondering how in the actual practice did they come up with the transformer's Core and Copper loss, the simple answer to that is through transformer test. The two known test that are used to find this intrinsic property of a transformer is the Open-Circuit test and the Short-Circuit Test. In an Open-Circuit Test (OCT) or (No Load Test). the purpose of this test is to determine the CORE loss. While in a Short-Circuit Test (SCT), the purpose of this test is to determine the equivalent impedance, equivalent reactance, equivalent resistance in which the measuring instruments are connected and to determine the full-load or rated Copper loss. For a detailed discussion regarding the topic of transformer test, click the link below. TRANSFORMER TESTS AND MEASUREMENTS