INTELLIGENT-FUZZY-CONTROLLER-FOR-A-LEAD-ACID.zip_battery_lead acid battery_数学计算

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta charset="utf-8"> <meta name="generator" content="pdf2htmlEX"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <link rel="stylesheet" href="https://static.pudn.com/base/css/base.min.css"> <link rel="stylesheet" href="https://static.pudn.com/base/css/fancy.min.css"> <link rel="stylesheet" href="https://static.pudn.com/prod/directory_preview_static/622b93f015da9b288b4de901/raw.css"> <script src="https://static.pudn.com/base/js/compatibility.min.js"></script> <script src="https://static.pudn.com/base/js/pdf2htmlEX.min.js"></script> <script> try{ pdf2htmlEX.defaultViewer = new pdf2htmlEX.Viewer({}); }catch(e){} </script> <title></title> </head> <body> <div id="sidebar" style="display: none"> <div id="outline"> </div> </div> <div id="pf1" class="pf w0 h0" data-page-no="1"><div class="pc pc1 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/622b93f015da9b288b4de901/bg1.jpg"><div class="t m0 x1 h2 y1 ff1 fs0 fc0 sc0 ls0 ws0">INTELLIGENT FUZZY CONTROLLER FOR A LEAD ACID</div><div class="t m0 x2 h2 y2 ff1 fs0 fc0 sc0 ls1 ws1">BATTERY CHARGER</div><div class="t m0 x3 h3 y3 ff1 fs1 fc0 sc0 ls2 ws2">G.E.M.D.C.Bandara*, Ratcho M. Ivanov and Stoyan Gishin</div><div class="t m0 x4 h3 y4 ff1 fs1 fc0 sc0 ls3 ws3">Department of Electronics Engineering, Faculty of Electronics</div><div class="t m0 x5 h3 y5 ff1 fs1 fc0 sc0 ls4 ws4">Sofia 1000, Bulgaria</div><div class="t m0 x6 h3 y6 ff1 fs1 fc0 sc0 ls5 ws5">Phone: +359-2636-2220, Fax: +359-2636-22220</div><div class="t m0 x2 h3 y7 ff1 fs1 fc0 sc0 ls6 ws6">Email*:dcb@aero.vmei.acad.bg</div><div class="t m0 x7 h4 y8 ff1 fs2 fc0 sc0 ls7 ws7">ABSTRACT: During the last ten years, fuzzy Control has emerged as the most popular method in non-linear process</div><div class="t m0 x7 h4 y9 ff1 fs2 fc0 sc0 ls7 ws8">control, due to the simplicity of implementation, robustness and independence from mathematical presentation of the</div><div class="t m0 x7 h4 ya ff1 fs2 fc0 sc0 ls8 ws9">control system. Fuzzy control can be applied to almost every control system, where mathematical model is not available</div><div class="t m0 x7 h4 yb ff1 fs2 fc0 sc0 ls7 wsa">or difficult to derive from existing data of the system.</div><div class="t m0 x7 h4 yc ff1 fs2 fc0 sc0 ls9 wsb">Fuzzy control of a Lead-Acid Battery Charger is being investigated in this paper. Effective control of the charging</div><div class="t m0 x7 h4 yd ff1 fs2 fc0 sc0 lsa wsc">process is complex due to the exponential relationship between the charging current and the charging time. Classical</div><div class="t m0 x7 h4 ye ff1 fs2 fc0 sc0 lsb wsd">control algorithms such as PID, PI etc., are difficult to implement in this event, due to the unavailability of the value for</div><div class="t m0 x7 h4 yf ff1 fs2 fc0 sc0 ls9 wse">the coefficient of discharge in the exponential current-time relationship and switching over of the control inputs during</div><div class="t m0 x7 h4 y10 ff1 fs2 fc0 sc0 lsc wsf">the two phases of the charging process.</div><div class="t m0 x7 h4 y11 ff1 fs2 fc0 sc0 ls9 ws10">Initial peak charging current is reduced stepwise during the charging time and the quantity of the energy necessary for</div><div class="t m0 x7 h4 y12 ff1 fs2 fc0 sc0 lsa ws11">the charging process is effectively reduced. An intelligent Microcontroller based digital architecture is developed to</div><div class="t m0 x7 h4 y13 ff1 fs2 fc0 sc0 lsb ws12">sense the charging current and the present charge, after which fast fuzzy inference mechanism defines the next level of</div><div class="t m0 x7 h4 y14 ff1 fs2 fc0 sc0 lsb ws13">the charging current. Delay time of the switching of the main supply is calculated after the fuzzy inference, and the</div><div class="t m0 x7 h4 y15 ff1 fs2 fc0 sc0 ls7 wsa">power switch is switched accordingly.</div><div class="t m0 x7 h4 y16 ff1 fs2 fc0 sc0 lsc ws14">Experimental results and expert knowledge are used for tuning of the membership functions and the rule base of the</div><div class="t m0 x7 h4 y17 ff1 fs2 fc0 sc0 lsd ws15">fuzzy controller.</div><div class="t m0 x7 h4 y18 ff1 fs2 fc0 sc0 ls9 ws16">Keywords: Fuzzy sets, fuzzy control, fuzzification, membership functions, regulator, fuzzy inference, defuzzification,</div><div class="t m0 x7 h4 y19 ff1 fs2 fc0 sc0 ls8 ws17">centre of gravity, microcontroller</div><div class="t m0 x7 h3 y1a ff1 fs1 fc0 sc0 lse ws6">INTRODUCTION</div><div class="t m0 x7 h4 y1b ff1 fs2 fc0 sc0 ls7 ws18">Rechargeable batteries have wide variety of applications not only in the automobile industry but also in</div><div class="t m0 x7 h4 y1c ff1 fs2 fc0 sc0 ls7 ws19">telecommunications, energy industry, medicine, defence applications and almost every where in industrial applications,</div><div class="t m0 x7 h4 y1d ff1 fs2 fc0 sc0 lsd ws1a">where continuos operating power is required. Methods used for charging such batteries vary depending on their</div><div class="t m0 x7 h4 y1e ff1 fs2 fc0 sc0 lsc ws1b">chemical composition, capacity, and methods of the construction and the type of the exploitation. Efficiency of the</div><div class="t m0 x7 h4 y1f ff1 fs2 fc0 sc0 lsc ws1c">charging algorithms are also depend on the amount of current used for the charging process, levels of the oscillations in</div><div class="t m0 x7 h4 y20 ff1 fs2 fc0 sc0 ls7 ws1d">the charging current, charging voltage levels, charging time and the fluctuations in the temperature during the charging</div><div class="t m0 x7 h4 y21 ff1 fs2 fc0 sc0 lsf ws6">process.</div><div class="t m0 x7 h4 y22 ff1 fs2 fc0 sc0 ls8 ws17">In this paper design of an intelligent universal battery charger, in which the control algorithm is implemented with fuzzy</div><div class="t m0 x7 h4 y23 ff1 fs2 fc0 sc0 lsc ws1e">logic is discussed. The intelligent digital architecture is implemented with Motorola's latest 16bit microcontroller</div><div class="t m0 x7 h4 y24 ff1 fs2 fc0 sc0 lsc ws1f">MC68HC812A4, which comes with a number of instructions specialised for fuzzy logic programming<span class="ls10 ws20"> <span class="ls11 ws21">(Bandara, 1997)<span class="ls12 ws6">.</span></span></span></div><div class="t m0 x7 h4 y25 ff1 fs2 fc0 sc0 ls7 ws22">Microcontroller's light integration module has almost all necessary peripherals to design this controller, but an external</div><div class="t m0 x7 h4 y26 ff1 fs2 fc0 sc0 ls13 ws23">analogue to digital converter is used for measuring the current and the voltage <span class="lsb ws24">to achieve high resolution.<span class="lsa ws25"> Implementing</span></span></div><div class="t m0 x7 h4 y27 ff1 fs2 fc0 sc0 lsd ws26">one of the very effective and latest charging algorithms with fuzzy logic is discussed in detail. The fuzzy control</div><div class="t m0 x7 h4 y28 ff1 fs2 fc0 sc0 lsd ws27">algorithm achieves the charging task in two phases. During the first phase the voltage is maintained below a maximum</div><div class="t m0 x7 h4 y29 ff1 fs2 fc0 sc0 lsd ws28">level given by the operator during the initial setting up process which is done in dialogue mode and the current is</div><div class="t m0 x7 h4 y2a ff1 fs2 fc0 sc0 ls8 ws29">regulated to the set maximum level. Set point of the current is closely related with the capacity of the battery and this is</div><div class="t m0 x7 h4 y2b ff1 fs2 fc0 sc0 ls14 ws2a">taken in to mind when writing the program. The second phase starts when the battery voltage reaches a specific value</div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div> </body> </html>

<div id="pf2" class="pf w0 h0" data-page-no="2"><div class="pc pc2 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/622b93f015da9b288b4de901/bg2.jpg"><div class="t m0 x7 h4 y2c ff1 fs2 fc0 sc0 ls15 ws2b">depending again on the capacity and number of cells available in the battery. During this phase control variable</div><div class="t m0 x7 h4 y2d ff1 fs2 fc0 sc0 ls16 ws2c">switches over from current to voltage and the voltage is maintained at a given by the operator level, while the current is</div><div class="t m0 x7 h4 y2e ff1 fs2 fc0 sc0 ls17 ws2d">gradually decreasing until it reaches a value set in the program depending on the capacity of the battery. A Lead-Acid</div><div class="t m0 x7 h4 y2f ff1 fs2 fc0 sc0 ls18 ws2e">battery is used during the experiments, but the device can also be connected to other types of rechargeable batteries</div><div class="t m0 x7 h4 y30 ff1 fs2 fc0 sc0 ls19 ws2f">such as Ni-Cd.</div><div class="t m0 x7 h4 y31 ff1 fs2 fc0 sc0 ls1a ws30">FUNDAMENTAL CONCEPTS OF EXPLOITATION AND CHARGING OF BATTERIES</div><div class="t m0 x7 h4 y32 ff1 fs2 fc0 sc0 ls1b ws31">There are two basic modes of exploitation of the batteries (Teoharov, 1995):</div><div class="t m0 x7 h4 y33 ff1 fs2 fc0 sc0 ls1c ws32">1. Continuos mode of exploitation</div><div class="t m0 x7 h4 y34 ff1 fs2 fc0 sc0 ls1d ws33">2. Standby or floating mode of exploitation.</div><div class="t m0 x8 h4 y35 ff1 fs2 fc0 sc0 ls1e ws34">Figure 1: Continuos mode of operation</div><div class="t m0 x7 h4 y36 ff1 fs2 fc0 sc0 ls1f ws35"> In<span class="ls20 ws36"> the first mode (Fig.1), the battery is connected to the charging device only after falling to provide the required</span></div><div class="t m0 x7 h4 y37 ff1 fs2 fc0 sc0 ls21 ws37">energy as a result of discharging the battery to a large extent due to a long period of exploitation. The battery is</div><div class="t m0 x7 h4 y38 ff1 fs2 fc0 sc0 ls22 ws38">disconnected from the load during the charging process and it consumes energy from the charging device. The battery</div><div class="t m0 x7 h4 y39 ff1 fs2 fc0 sc0 ls23 ws39">is connected to the charging device and the load simultaneously during the second mode of operation (Fig. 2).</div><div class="t m0 x9 h4 y3a ff1 fs2 fc0 sc0 ls24 ws3a">Figure 2: Stand-by mode of operation</div><div class="t m0 x7 h4 y3b ff1 fs2 fc0 sc0 ls25 ws3b">The charging device has two distinctive types of functions during this mode of operation. First, the charging device</div><div class="t m0 x7 h4 y3c ff1 fs2 fc0 sc0 ls26 ws3c">functions as a current generator, immediately after the discharging of the battery. The high initial current is</div><div class="t m0 x7 h4 y3d ff1 fs2 fc0 sc0 ls21 ws3d">characteristic for this mode and it secures quick charging of the battery at the beginning of the charging cycle, where</div><div class="t m0 x7 h4 y3e ff1 fs2 fc0 sc0 ls27 ws3e">80% - 90% of the capacity is charged. The charging device moves onto the second phase when the voltage reaches the</div><div class="t m0 x7 h4 y3f ff1 fs2 fc0 sc0 ls28 ws3f">required value. The charging device has the function of a voltage generator at the second phase and the fixed voltage,</div><div class="t m0 x7 h4 y40 ff1 fs2 fc0 sc0 ls22 ws40">which was achieved at the first stage, is continuously maintained. The battery consumes only an amount of current that</div><div class="t m0 x7 h4 y41 ff1 fs2 fc0 sc0 ls29 ws41">is required for the charging process. Therefore the current gradually decreases and stabilises at a value which is called</div><div class="t m0 x7 h4 y42 ff1 fs2 fc0 sc0 ls2a ws42">"current of the under charge". This low current compensates self-charging current of the battery.</div><div class="t m0 x7 h3 y43 ff1 fs1 fc0 sc0 ls2 ws43">METHODS FOR CHARGING THE BATTERIES</div><div class="t m0 x7 h4 y44 ff1 fs2 fc0 sc0 ls1e ws44">The charging devices of batteries function in a specific mode where the load has a capacitive character and can be</div><div class="t m0 x7 h4 y45 ff1 fs2 fc0 sc0 ls2b ws45">considered as an infinite capacitor, which has the equivalent circuit shown in the Figure 3.</div><div class="t m0 xa h4 y46 ff1 fs2 fc0 sc0 ls2c ws46">Figure 3: Equivalent circuit of a charging process</div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div>

<div id="pf3" class="pf w0 h0" data-page-no="3"><div class="pc pc3 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/622b93f015da9b288b4de901/bg3.jpg"><div class="t m0 x7 h4 y2c ff1 fs2 fc0 sc0 ls2d ws47">The internal resistance of the battery is defined as 0.25/ Q per battery cell, (Teoharov, 1995)<span class="ls10 ws48"> <span class="ls2e ws49">where Q is the capacity of</span></span></div><div class="t m0 x7 h4 y2d ff1 fs2 fc0 sc0 ls2f ws4a">the battery. As an example, let's consider a 12V battery, consisting of six cells and has the capacity of 120Ah. Internal</div><div class="t m0 x7 h4 y2e ff1 fs2 fc0 sc0 ls30 ws4b">resistance of this battery can be calculated as follows:</div><div class="t m0 xb h5 y47 ff1 fs2 fc0 sc0 ls31 ws4c">0.25 / 120 = 0.00208 x 6 = 0.0125 <span class="ff2 ls32 ws6">Ω</span></div><div class="t m0 x7 h4 y48 ff1 fs2 fc0 sc0 ls33 ws4d">If the charging device is assumed to have fluctuations of the output voltage at levels of 600mV - 800mV, the coefficient</div><div class="t m0 x7 h4 y49 ff1 fs2 fc0 sc0 ls34 ws4e">of the fluctuations becomes 9.6% and the pulsating charge current has the following value:</div><div class="t m0 xc h4 y4a ff1 fs2 fc0 sc0 ls20 ws4f">0.8 / 0.0125 = 64A</div><div class="t m0 x7 h4 y4b ff1 fs2 fc0 sc0 ls33 ws50">This pulse can destroy the battery if it is not maintained below the required level. This example shows us that the level</div><div class="t m0 x7 h4 y4c ff1 fs2 fc0 sc0 ls35 ws51">of fluctuations of the charging current must be limited in order to avoid heating and boiling of the acids in the</div><div class="t m0 x7 h4 y5 ff1 fs2 fc0 sc0 ls36 ws52">composition and to increase the durability of the battery.</div><div class="t m0 x7 h4 y4d ff1 fs2 fc0 sc0 ls37 ws53">There are a number of methods for charging the batteries (Teoharov, 1995).</div><div class="t m0 x7 h4 y4e ff1 fs2 fc0 sc0 ls38 ws54">1. Charging with constant current</div><div class="t m0 x7 h4 y4f ff1 fs2 fc0 sc0 ls39 ws55">2. Charging with a semi-constant current</div><div class="t m0 x7 h4 y50 ff1 fs2 fc0 sc0 ls3a ws56">3. Charging with constant voltage</div><div class="t m0 x7 h4 y51 ff1 fs2 fc0 sc0 ls3b ws57">4. Multistage charging according to the Ampere - Hour rule and two stage charging cycle which simplifies the</div><div class="t m0 x7 h4 y52 ff1 fs2 fc0 sc0 ls1d ws58">multistage charging method, where the charging cycle at first with a constant current and next with constant voltage.</div><div class="t m0 x7 h4 y53 ff1 fs2 fc0 sc0 ls1c ws59">The first method is rarely used in general application, but is very effective when charging a large number of serially</div><div class="t m0 x7 h4 y54 ff1 fs2 fc0 sc0 ls35 ws5a">connected batteries. This method has a small coefficient of efficiency and adversely effect over the characteristics of the</div><div class="t m0 x7 h4 y55 ff1 fs2 fc0 sc0 ls2c ws5b">battery and the durability, while the second method has very simple architecture consisting of a transformer, rectifier</div><div class="t m0 x7 h4 y56 ff1 fs2 fc0 sc0 ls3c ws5c">bridge and a current limiting resistor as shown in Figure 4.</div><div class="t m0 xd h4 y57 ff1 fs2 fc0 sc0 ls26 ws5d">Figure 4: Charging with a semi-constant current</div><div class="t m0 x7 h4 y58 ff1 fs2 fc0 sc0 ls3d ws5e">This method is also called as "Taper charging" and it is also not recommendable due to constant current characteristics</div><div class="t m0 x7 h4 y59 ff1 fs2 fc0 sc0 ls3e ws5f">of the charging device adversely effect especially the Lead - acid batteries. Batteries are normally overcharged due to</div><div class="t m0 x7 h4 y5a ff1 fs2 fc0 sc0 ls3f ws60">the very high current and reduce life of the batteries. This method also characterises a low coefficient of efficiency due</div><div class="t m0 x7 h4 y5b ff1 fs2 fc0 sc0 ls30 ws61">to the resistor and initial current limitation is required. In the third method (Fig. 5) initial charging current is very high,</div><div class="t m0 x7 h4 y5c ff1 fs2 fc0 sc0 ls40 ws62">but is maintained below a certain level (10% -25% of the capacity of the battery) to protect the battery. The current</div><div class="t m0 x7 h4 y5d ff1 fs2 fc0 sc0 ls2c ws63">gradually decreases towards the end of the charging cycle. Charging voltage must be set depending on the capacity of</div><div class="t m0 x7 h4 y5e ff1 fs2 fc0 sc0 ls41 ws64">the battery and it's temperature characteristics.</div><div class="t m0 xe h4 y5f ff1 fs2 fc0 sc0 ls42 ws65">Figure 5: Charging with a constant voltage</div><div class="t m0 x7 h6 y60 ff1 fs2 fc0 sc0 ls43 ws6">The<span class="ff3 ls10 ws66"> </span><span class="ls44 ws67">forth method is widely accepted as the best and is discussed below in detail.</span></div><div class="t m0 x7 h4 y61 ff1 fs2 fc0 sc0 ls45 ws68">This method is recommended to charging the Lead - acid batteries with in a short time and maintains the battery in</div><div class="t m0 x7 h4 y62 ff1 fs2 fc0 sc0 ls46 ws69">standby mode.</div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div>