电气自动化外文及翻译-电气类(编辑修改稿)

电气自动化外文及翻译-电气类(编辑修改稿)内容摘要：

nd evaluated. Section 4 presents the new divide and conquer pulsecharging method. Section 5 concludes the paper. 3. Three Intelligent Charging Methods In a basic battery, a chemical reaction takes place inside the battery and releases energy in the form of charge during usage. Once the chemical reaction is finished, the battery is “spent” or discharged. The idea behind charging is to put energy back into the battery to be stored and used again. As the most damage done to a battery is usually while it’s being charged, intelligent control is necessary to properly charge a battery. There are several ways to do acplish this task. The most mon and recently developed methods are as described below: Galvanostatic Charging: The most mon and direct approach is to charge a battery is to force energy back into a battery by applying a higher potential across the terminals. As the name “Galvanostatic” implies, this technique involves driving a constant current into the battery. This method can be used to charge the battery quickly and is simple to implement. PulseCharging: A second, and more recently developed, method of charging is called “pulse charging.” This method also involves sending charge back into the battery。 however, it is not done at constant current. Instead, pulsecharging cycles between a period of constant current into the battery and a brief moment of rest, as seen in Figure 1. The idea behind this technique is to allow time for the chemical reaction to settle, so the battery is charged more uniformly. This minimizes problems with the formation of the physical chemical make up of the battery – hence reducing longterm damage to the battery. BurpCharging: Along with the development of the pulsecharging method, another similar method was developed, called “Burp” charging. The name came from a very brief moment of discharge within the pulsecharge cycle (optimal discharge pulse relative to charge cycle can be calculated from algorithm discussed later). The idea behind the discharge pulse is to redirect the migration of oxide gas away from the reacting plates, preventing oxidization, allowing the battery to prolong its life and capacity. Figure 1. Typical PulseCharge Cycle (only burpcharge has discharge pulse). The development of the above three methods of intelligent charging led to studies to determine their effectiveness. One of the most thorough studies was done by NASA Johnson Space Center on battery life under these methods of charging Darcy. The NASA study examined battery capacity and life cycles through various charge methods. The data result from testing NiMH charge using pulse, burp, galvanostatic, and galvanostatic to 45o C (constant charge current until battery temperature reaches 45o C – note that once battery is full, extra energy is converted to heat). The test result indicate that galvanostatic to 45o C produces the worst result, while the other three methods produce seemingly the same pattern as far as charge capacity, pulsecharge and burpcharge does extend battery life toward the end. The NASA study also looked at the heat and gas generation by various charge methods. In respect to gas generation, pulsecharge and burpcharge consistently produces less gas than galvanostatic method. As for heat generation, pulsecharge and burpcharge produces less heat than the conventional galvanostatic method again – with significant improvement from the burpcharge method. Note that excess heat is very damaging to a battery. From available literature and data, a conclusion can be drawn that pulsecharging methods – inclusive of both pulsecharge and burpcharge – are superior to the conventional galvanostatic method. It can prolong the battery life, reduces gas and heat generation while charging (whi。