Simple battery chargers may leave the battery inadequately charged and can even pose serious safety hazards. In the intelligent battery charging technology, however, the microcontroller provides the intelligence to overcome these problems
By Srabani Sen
Wednesday, August 19, 2009: Paperless warranty
When a customer purchases a UPS or an inverter, he may face a lot of issues regarding warranty. Either the dealer or distributor does not hand over the warranty card to the customer or keeping track of paper receipts becomes an encumbrance for the user. Sometimes, even the date on the warranty card is missing. To top it all, adopting unscrupulous means to keep customers in the dark concerning warranty details is also a common practice.
Now, UPS and inverters offer a technology enabled service intended to make warranty issues simpler for users, while also helping them to go green. It is called digital paperless warranty—a technological trend that takes care of warranty related issues. Manufacturers are increasingly opting for this technology.
UPS and inverters are basically micro-controller based systems. When you switch on the inverter or UPS for the first time, the microcontroller can do real time data logging. It will log in the data that will indicate the date of the first usage of the inverter or UPS. This date gets logged on to the memory of the microcontroller and after about six months or so, if there is a problem with the device, the user can see the warranty information directly from the memory of the microcontroller, as it is equipped with a built-in recorder system. This takes care of all issues related to the warranty card and can check misuse of warranty as well.
By using a micro-controller, a battery charger can also be made intelligent. There is a charging section in the inverter and UPS which is connected to a battery. There is also an input and an output section. Improvement is taking place in all three of these sections. Today, manufacturers are substituting the bulky transformer based charger with switch mode power supply chargers. These are highly efficient, low weight, low cost chargers with built-in fuzzy logic control for trickle charging. Fuzzy logic control aids in proper charging of the battery at the pre-determined level. This concept is called intelligent battery charging.
Simple battery chargers do not possess the intelligence to charge different battery technologies or batteries with the same technology. They may leave the battery inadequately charged and can even pose serious safety hazards. In the intelligent battery charging technology, however, the microcontroller provides the intelligence to overcome these problems.
This is also a built-in feature in UPS and inverters, which ensures that in case of two or more battery connections, the equaliser, which incorporates a cell balancing scheme, prevents individual cells from becoming overstressed. It helps to equalise the batteries and increases their life by more than 200 per cent. It also assists in providing better backup time and takes into account the ageing and operating conditions of the cells.
Intelligent battery monitoring, another built-in technology in UPS and inverter systems, helps to monitor battery voltage, actual charging/ discharging current, battery temperature and ambient temperature and records the number of charge
and discharge cycles the battery goes through. It has an intelligent algorithm, which can measure the health of the battery. Through this monitoring system, the user can assess the state of health of batteries and can examine this data in order to predict potential failures and take preventative measures.
This system monitors the state of charge of each cell. Also, it monitors less critical and low cost applications. Switching circuits control the charge applied to each individual cell in the chain during the charging process to equalise the charge on all the cells in the pack.
INTELLIGENT LOAD SHARING
This intelligent technology enables the user to prioritise different electrical loads. These systems have multiple outputs for connecting to loads and each of these prioritised outputs can be independently controlled. For instance, in a hospital, the priority one load may be the operation theatre. Similarly, in a retail chain, the IT server may be the first priority, so that the billing operations continue without any interruptions. The hospital and the retail chain may also have lower priority loads. For example, lighting could be a lower priority load in some areas of the hospital, which can be turned off for some time.
Intelligent load sharing helps to segregate the loads in an intelligent way. Once the main goes off and the load switches to battery mode, the battery level de-escalates to a certain level. The battery will then automatically cut off the lower priority load and divert the current to the higher priority load. It will ensure that the user’s highest priority runs smoothly all the time. The optimisation of the load is based on priority levels. Such a system is the need of the hour in all critical application areas like hospitals, retail chain stores, shopping malls, etc.
HIGH FREQUENCY DEVICES
These high frequency based UPS and inverters render numerous advantages because they reduce the overall system cost, weigh less and also get improved system performance. However, in India, this system has been a failure so far because manufacturers have not designed these products well.
High frequency products emit high frequency radiation as power devices are switched at high speeds. They, therefore, need to be guarded against electromagnetic interference (EMI) and are designed for electromagnetic compatibility (EMC).
Today, the trend is to create products based on high frequency, which are sleek and smaller in size but are still EMI and EMC compatible.
Usually, UPS and inverters lack a system where the hardware can be automatically configured. Now, manufacturers are going in for configurable processors, through which many hardware blocks can be configured dynamically, such as pulse width modulators (PWMs), analogue-to-digital conversion channels, general purpose input/outputs, etc. Information provided by Venkat Rajaraman, CEO, Su-Kam Power Systems.
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