Analysis of Technical Loss Calculation Using Load Curve Approach on 20 kV Distribution Network

Rizky Rahmat Maulana1, Salahuddin1, Ezwarsyah1, Baharuddin Ismail2, Ashish Shrestha3, & Dhiraj Vijayrao Astonkar4,5 1 Department of Electrical Engineering, Malikussaleh University, Bukit Indah, Lhokseumawe, Indonesia, 24351 2 University Malaysia Perlis, Perlis, Malaysia 3 University of South-Eastern Norway, Norway 4 Dr. Sau Kamaltai Gawai Institute of Engineering and Technology, Darapur, Dist. Amravati, Maharashtra, India 444814 5 Sant Gadge Baba Amravati University, Amravati, Maharashtra, India, 444702


Introduction
Electrical energy is one of the most vital needs for people's lives today. Because all activities related to daily needs cannot be separated from the need for electrical energy. This makes electrical energy a very important basic need for people's lives today. To overcome the need for electrical energy, the government has also thought about it, among others, through the construction of large and small-scale power plants. By managing and increasing natural resources that can be used as electricity generation. So that electrical energy can be distributed throughout the region through the transmission network and distribution network. The electrical system as a whole includes the generation, transmission, and distribution sections.
The distribution system that functions to distribute and distribute electrical energy to consumers needs adequate quality. In the distribution of electric power, not all of it can be distributed to consumers, because it will be lost in the form of energy loss.
The appearance of shrinkage is caused by technical and non-technical causes. The cause of technical shrinkage occurs because of the impedance in the electrical components so that power is lost in the form of heat. The causes of nontechnical losses occur due to inaccuracies in measuring and using electrical energy on the customer side.
After the electrical energy is channeled through the primary distribution network, then the electric power will be lowered again at the distribution substations to a low voltage with a voltage of 380/220 Volts which will then be channeled through the low voltage network to customers' homes via a connection house

Primary Distribution Network
The primary distribution system is used to distribute electric power from the distribution substation to the load center. This system can use overhead lines, overhead cables, or ground cables according to the desired level of reliability and environmental conditions and situations. This distribution channel is stretched along the area to be supplied with electric power to the load center. Based on the function and use of a feeder, it can form several types of primary distribution network systems into four, namely, radial systems, loop systems, spindle systems and mesh systems.

Secondary Distribution Network
The secondary distribution system is used to distribute electric power from the distribution substation to the loads on the consumer. In the secondary distribution system, the most widely used channel form is the radial system. This system can use insulated cables or conductors without insulation. Looking at its location, this distribution system is the part that is directly related to consumers, so this system functions to receive electrical power from a power source (distribution transformer), will also send and distribute the power to consumers. considering that this section is directly related to consumers, the quality of electricity should be very concerned. Electrical power distribution systems on Low Voltage Networks can be divided into two, namely as follows: -Low Voltage Air Line The type of conductor used is bare cable (without insulation) such as AAAC cable, ACSR cable. -Low Voltage Air Cable Channels The type of conductor used is insulated cable such as LVTC cable (Low Voltage Twisted Cable). LVTC cable sizes are: 2x10 mm 2 , 2x16 mm 2 , 4x25 mm 2 , 3x 3 5mm 2 , 3x50 mm 2 , 3x70 mm 2 . According to SPLN No. 3 of 1987, low voltage network is a low voltage network that includes all parts of the network and its equipment, from low voltage distribution sources to limiting/measuring devices. which connects the STR with the limiter/measuring device).

Electrical Energy Loss
Losses is a form of loss of electrical energy that comes from the difference between the amount of electrical energy available and the amount of electrical energy sold. • Non -technical loss Non-technical losses are the loss of electrical energy consumed by customers and non-customers because they are not recorded in sales. There are several causes of non-technical losses, including electricity theft, meter reading errors, measurement tool errors and others. Meter reading errors cause a mismatch between the kWh used by the customer and the recorded one. If what is used turns out to be greater than what was recorded, the difference will certainly be reduced. There are efforts to overcome these problems, one of which is by providing guidance and training to human resources involved in the meter reading process up to the application of meter reading applications and methods. The measurement tool error causes the measured energy does not match the energy used by the customer. This can be caused by kWh meter, wiring, CT/PT, and other factor errors. To overcome this, it can be done with periodic kWh replacement and routine inspections. b. Based on the place of occurrence • Transmission loss Namely the loss of electrical energy generated when it is distributed through the transmission network to substations or technical losses that occur in the transmission network which includes losses in the High Voltage network (JTT) and at the Substation (GI).
• Distribution shrink That is the loss of electrical energy distributed from substations through distribution networks to customers or technical and non-technical losses that occur in the distribution network which includes medium network losses, distribution substations, low voltage networks home connections and Limiting and Measuring Devices for high voltage, medium voltage and low voltage customers. If there is a high-voltage network that functions as a distribution network, this network loss is intended as a distribution loss.

Research Methods
The methods used in this research include: a. Data collection technique -Study of literature Literature study, namely obtaining information through reference books related to the object of research, journal articles, internet access and guidance from teaching staff in order to obtain the necessary data. b. Field Data Collection In the object of this research, it is known that the single line diagram of the 20 kV medium distribution network system is as shown below:

Assumption Data
For the calculation of this technical loss, the following assumption data are taken: 1. The value of the medium voltage network load factor for each month is the same. 2. It is assumed that the conductor resistance value for all cables is the conductor resistance value for the 3×150 mm^2 AAAC type cable 3. The value of transformer losses for all transformers uses the value of the transformer loss with a capacity of 250 kVA, for the value of transformer losses, namely Iron Loss and Copper Loss using the provisions of SPLN No. 50 of 1997.  For other months the calculation is the same as above. So that the results of technical losses on Distribution Transformers can be seen as in Table 4.

Calculating of Total Technical Losses
The calculation of the total technical loss is carried out at intervals of every onemonths. Systematically, the calculation of the total loss between the medium voltage network and the Distribution Transformer can be done as follows: 1. For other months the calculation is the same as above. So that the results of total shrinkage can be seen as in Table 5.

Technical Shrinkage Composition
From the analysis of the data above, a graph of the composition of technical losses at PT PLN (Persero) ULP MatangGlumpangDua can be made as follows:

Load Curve
After calculating the technical losses on the Medium Voltage Network and Distribution Transformer, the writer then modeled the calculation results with a load curve approach. From the load curve profile, it can be seen that the input kWH and the composition of the technical losses in the Medium Voltage Network and Distribution Transformer have been calculated.
Based on Table 5