MOTORS AND POWER SUPPLY - Electrical Articles

Stator Voltage Control of Induction Motors

Introduction Stator Voltage Control of an Induction Motor is used generally for three purposes – (a) to control the speed of the motor (b) to control the starting and braking behaviour of the motor (c) to maintain optimum efficiency in the mo ...

0 Comments. 4726 views since Oct 1, 2008

DC Motors Using H Bridge

An electric motor converts electrical energy into mechanical energy. The reverse process that of converting mechanical energy into electrical energy is accomplished by a generator or dynamo. Traction motors used on locomotives often perform both tasks ...

2 Comments. 2469 views since Sep 27, 2007

Bio Batteries

Almost any liquid or moist object that has enough ions to be electrically conductive can serve as the electrolyte for a cell. As a novelty or science demonstration, it is possible to insert two electrodes made of different metals into a lemon, potato e ...

0 Comments. 1712 views since Nov 29, 2007

Battery Management in UPS Systems

Battery Lifetime and UPS Reliability The battery is the least reliable part of most well designed UPS systems. This is very important to the user, because UPS battery replacement is expensive (as much as 30% of the original cost of the UPS). Fa ...

0 Comments. 1185 views since Oct 1, 2008

Single - Phase Induction Motors

A three phase motor may be run from a single phase power source. (Figure:1 below) However, it will not self-start. It may be hand started in either direction, coming up to speed in a few seconds. It will only develop 2/3 of the 3-φ power rating becaus ...

1 Comments. 1022 views since Oct 21, 2008

Power Supply of Mobiles

 Power is the primary challenge facing the mobile small computing industry. Consumer expectations are high for mobile small computing devices. They want desktop performance anytime and anywhere they power up. Unfortunately, improvements in power ...

0 Comments. 943 views since Jun 17, 2008

Uninterruptible Power Supplie (UPS) - Common Topologies

Introduction Within thephotoelectric-sensor arena, the diffuse sensing mode has become muchmore prevalent with the development and refinement of backgroundsuppression—the ability of a sensor to see an object and ignore thereflective su ...

0 Comments. 880 views since Oct 1, 2008

Voltage Collapse in Power Systems

Introduction Uncontrollable decay of system voltage at one or more load buses or even over a significant portion of the network as a response to load variations, generation or structure disturbances etc has been observed in Power systems world ...

0 Comments. 853 views since Oct 1, 2008

Batteries: Electron activity in Chemical Reactions

Lets see in detail how batteries function.Before reading the artcle you might have simply assumed that batteries produce constant voltage through some sort of mysterious process. Here, we will explore that process to some degree and cover some of the p ...

0 Comments. 810 views since Oct 23, 2008

Making Motors & Drives

Electric motors and drives improve year after year more as an evolutionary process than by revolutionary developments. Since these smaller motors and drives are integrated into robotics systems, they are helping to bring new levels of efficiency and pr ...

0 Comments. 794 views since Sep 26, 2008

Batteries: Practical Considerations

When connecting batteries together to form larger "banks" (a battery of batteries?), the constituent batteries must be matched to each other so as to not cause problems. First we will consider connecting batteries in series for greater voltage: < ...

0 Comments. 779 views since Oct 23, 2008

Battery Construction

The word battery simply means a group of similar components. In military vocabulary, a "battery" refers to a cluster of guns. In electricity, a "battery" is a set of voltaic cells designed to provide greater voltage and/or current than is possible with ...

0 Comments. 778 views since Oct 23, 2008

Power Management: Critical Choices for Wireless

In the past, the devices making up sensor networks received power through the hard-wired infrastructure; managing this essential operational resource meant simply guaranteeing clean, constant electrical energy. If the electrical system was in good work ...

0 Comments. 749 views since Oct 7, 2008

Battery Ratings

As the batteries create electron flow in a circuit by exchanging electrons in ionic chemical reactions, and there is a limited number of molecules in any charged battery available to react, there must be a limited amount of total electrons that any bat ...

0 Comments. 673 views since Oct 23, 2008

Special - Purpose Batteries

Back in the early days of electrical measurement technology, a special type of battery known as a mercury standard cell was popularly used as a voltage calibration standard. The output of a mercury cell was 1.0183 to 1.0194 volts DC (depending on the s ...

0 Comments. 666 views since Oct 23, 2008