Sistem Penyimpanan Daya Listrik (Batere)

Transkripsi

1 DTG1I1 Sistem Penyimpanan Daya Listrik (Batere) By Dwi Andi Nurmantris

2 Telecommunication Power system 1. Rectifiers 2. Battery 3. Charge bus 4. Discharge bus 5. Primary Distribution systems 6. Secondary Distribution systems 7. Voltage converters 8. Prime and standby ac power systems 9. Alternating current power distribution system 10.Load equipment 11.Monitoring and control system

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4 BATERAI Baterai adalah elemen (sel) sumber arus listrik searah. Baterai adalah alat untuk mengubah energi kimia menjadi energi listrik. Batteries are the energy storage component in a telecommunications power system Baterai biasanya terdiri atas beberapa buah sel listrik. Jika dalam sel listrik itu terjadi reaksi kimia, pada kedua elektronnya akan mempunyai beda potensial.

5 Jenis Baterai Baterai types are categorized as secondary batteries, which indicates they are rechargeable rechargeable battery and primary batteries, which are not rechargeable and are not used in telecommunications applications Disposable(sekali pakai) battery. The basic battery technology most often used is lead acid. Two types are used: Vented lead acid (VLA) and allows the gases to freely escape from the cell container valve-regulated lead acid (VRLA) VRLA limits the amount of gases that escape except under abnormal conditions.

6 Disposable Battery

7 Sistem Penyimpanan Daya Listrik (Batere) Disposable Battery

8 Rechargeable Battery

9 Baterai Component and charge discharge Process Lead Acid Batery Cells have three active components : negative electrode (or plate) of almost pure sponge lead (Pb) Katoda positive plate of pasted lead dioxide (PbO2, also called lead peroxide) anoda electrolyte of water-diluted sulfuric acid (H2SO4)

10 Baterai Component and charge discharge Process

11 Kapasitas Baterai The total energy contained within a battery can be described using Amp-hours (AH) Ampere-hours indicate the load current measured in amperes that may be drawn from the battery over a time period measured in hours. For example, if a 12-cell battery is discharged to an end voltage of 21.0 V (1.75V/cell) by a load of 12 A in 8 h, the battery capacity supplied to the load under those conditions is 12 A 8 h = 96 Ah Vented lead acid (VLA)cells range in capacity from about 50 to 8000 Ah VRLA cells range in capacity from much less than 50 Ah to around 2000 Ah

12 Seri dan Parallel Battery

13 Karakteristik Batere untuk Telekomunikasi Battery untuk BTS Telekomunikasi biasanya menggunakan battery FA (Front Acces). Battery ini modelnya lebih tipis dari battery model battery ups. Dan terminal battery ini terletak di depan sehingga gampang untuk koneksinya A telecommunications battery spends most of its life in the fully charged state Depending on the length of time that rectifiers are not available due to ac power source failure, the discharge portion of the cycle could last from a few minutes to 12 h or more. The battery discharges at a rate determined by the reserve time and discharge current. Upon restoration of the rectifier s ac power source, a fully discharged battery recharges in (typically) 8 to 24 h and then floats at a constant voltage until the next power source failure

14 Karakteristik Batere untuk Telekomunikasi Lead Acid Cell Discharge Curve Float Voltage Float voltage is the voltage at which a battery is maintained after being fully charged to maintain that capacity by compensating for self-discharge of the battery Self Discharge A cell will discharge even if it is not connected to a load Self-discharge rate increases with temperature and age Typical self-discharge values at 25 C (77 F) : 6 to 7% per month for lead antimony VLA 3% per month for lead calcium VLA 1 to 2% per month for VRLA Overdischarge A cell will become overdischarged if it drops below its rated final cell voltage. Overdischarge may cause the plates to buckle and the grids to crack. Continued overdischarge may reverse the polarity, and destroys the cells

15 Karakteristik Batere untuk Telekomunikasi Lead Acid Cell Temperatur Performance Telecommunications batteries are optimized for operation at 25 C (77 F) Operation at lower temperatures generally will increase battery life but it lowers battery capacity

16 Karakteristik Batere untuk Telekomunikasi Lead Acid Cell End of Life Telecommunications batteries are considered at the end of their useful life when their capacity decreases to 80% of nameplate. For example, when the capacity of a 1000-Ah battery decreases to 800 Ah, the battery is, by definition, at end of life Cycling (discharging and charging) will decrease the battery life A battery that is seldom or lightly cycled will last longer than a battery that is continuously and deeply cycled

17 Karakteristik Batere untuk Telekomunikasi Lead Acid Cell End of Life Most telecommunications applications are subject to long float periods with occasional cycling. The amount and depth of cycling depends on several factors : o Depth of discharge (DoD) the lower a battery is discharged (greater depth of discharge), the shorter its life o Amount of recharge before the next discharge cycle if a battery is not fully recharged before the next outage that causes a discharge, the shorter its life o Length of time in the discharged state the longer a battery remains in the discharged state before it is recharged, the shorter its life

18 Baterai Cell Configuration for telecommunication A cell is the basic electrochemical unit in a battery At a minimum a cell consists of two electrodes immersed in an electrolyte, in a container (or jar) Batteries used in telecommunications usually consist of 12 cells (24 V nominal system voltage) or 24 cells (48 V) connected in series.each lead acid cell has a nominal voltageof 2 V The series cell combination is called a battery string

19 Baterai Cell Configuration for telecommunication Battery strings are connected in parallel to provide higher capacity

20 INTERMEZO

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