INTRODUCTION

 Finding an idea that you can turn into a successful business is the first - and often the biggest - stumbling block for budding entrepreneurs. Many people want to run their own business and have the aptitude to do it, but struggle to pin down a viable idea.All businesses must meet a customer’s need or provide asolution to a customer’s problem. With this in mind, the following 20 tips will help inspire you to think practically about the products or services you could offer, and the business opportunities that may be open to you.
USE YOUR EXISTING SKILLS TO CREATE A SPECIALISED PRODUCT
Could you use or adapt the skills and experience that you gained while working for somebody else, to focus on the needs of a niche market? For example, if you worked in a factory making a large range of wooden furniture, you could concentrate on making a limited range of quality furnishings such as beds. This means that you wouldn’t have to compete against well-established carpenters doing joinery work in people'shomes.Instead of starting a salon, a hairdresser could specialisein styling the hair of brides and  bridesmaids in their homes,so that they don't have to rush into town to get their hair done on their wedding
TURN YOUR HOBBY INTO A MONEY MAKER
Could you earn money from your hobby, and turn it into aviable business?For example, do you like gardening? Could you set up a landscape gardening business? Do you enjoy cooking?What about a catering service for people having parties at home, or a specialist cake-making business? Don't ignore your hobby as a business idea just because you do it for fun; somebody may be willing to pay for it.Besides, a lot of the success of your business will come from the amount of work and enthusiasm you put into it, so it helps to have an idea based on something you enjoy doing already.

SOCIAL TRENDS

Think about changes in society that might lead to new business ideas. For example, there are now more single people than ever, so what about a business as a personal advertisement writer to help them meet new people.

WhAT TYPE OF PERSON ARE YOU?
Does your personality suggest any business ideas?If you have persistence, mischievous charm and the ‘gift of the gab’, you might be a good salesperson. There are frequent openings for self-employed salespeople to sell other people's products. If you are good at dealing with people, you might be just the person to take up a retail franchise, party planning opportunity or multi-level marketing scheme. Find out more about direct selling opportunities you are one of the thousands of people who enjoy selling their surplus household items at markets or fêtes, youcould start a legitimate business trading over the InterneT by opening your own online shop. Specialist suppliers such as businesses selling vintage clothing to a niche market are often particularly successful.for ideas and products to specialise in.out a business as a personal advertisement writer to help them meet new people.

What's missing locally?

Look around in your own local area. Think of the problems

and difficulties that you have experienced in getting things

for your home, or at work, or in your leisure activities:

•

cost you the most (in time, effort or money) to

correct?

What problems inconvenience you the most, or

•

most need it?

What service is not available locally when you

•

impossible to get locally?

Which products or services are hard or

•

complain about most often?

What do you and your neighbours and friends

•

example, a sandwich delivery service to office

blocks or business parks far from shops.)

Listen to people talking in the supermarket queue, at the

bus stop or at the taxi rank. Find out what it is that they

have difficulty getting hold of. Is there any way of providing

a local service or product for any of these markets, which

somebody will pay for? You can research local businesses

by checking out directories like Yellow Pages

(www.yellowpages.co.za), as well as your local Chamber

BELOW ARE LIST OF BUSINESS OUTLINES BELOW
Agro-Business.
-Aquatic
-exortic cattle farming
-ostrich farming(highly profitable)
 -Plantation
-Vegetation
 -snail farming
COMMUNICATION BUSINESS
-e-commerce
-recharge card print
-e-post
OIL AND GAS
-
ELECTRICITY AND ELECTRONICS BUSINESS
Building and Installation of Electricity generators e.t.c
electricity Inverter and installation.
schematic diagrams of various kva's power generators

enthusiastic Knowledge of Inverter building and Installation.

Background

DC and AC Current

             In the world today there are currently two forms of electrical transmission, Direct Current (DC) and Alternating Current (AC), each with its own advantages and disadvantages. DC power is simply the application of a steady constant voltage across a circuit resulting in a constant current. A battery is the most common source of DC transmission as current flows from one end of a circuit to the other. Most digital circuitry today is run off of DC power as it carries the ability to provide either a constant high or constant low voltage, enabling digital logic to process code executions. Historically, electricity was first commercially transmitted by Thomas Edison, and was a DC power line. However, this electricity was low voltage, due to the inability to step up DC voltage at the time, and thus it was not capable of transmitting power over long distances4. V =IR ,P=IV              As can be seen in the equations above, power loss can be derived from the electrical current

squared and the resistance of a transmission line. When the voltage is increased, the current decreases and concurrently the power loss decreases exponentially; therefore high voltage transmission reduces power loss. For this reasoning electricity was generated at power stations and delivered to homes and businesses through AC power. Alternating current, unlike DC, oscillates between two voltage values at a specified frequency, and its ever changing current and voltage makes it easy to step up or down the voltage. For high voltage and long distance transmission situations all that is needed to step up or down the voltage is a transformer. Electrical transmission has therefore been mainly based upon AC power, supplying most homes.        Like DC power, there exist many devices such as power tools, radios and TV’s that run off of AC power. It is therefore crucial that both forms of electricity transmission exist; the world cannot be powered with one simple form. It then becomes a vital matter for there to exist easy ways to transform DC to AC power and vice versa in an efficient manner. Without this ability people will be restricted to

what electronic devices they use depending on the electricity source available. Electrical AC/DC converters and DC/AC inverters allow people this freedom in transferring electrical power between the two.      

   An inverter is an electrical device that converts direct current (DC) to alternating current (AC); the converted AC can be at any required voltage and frequency with the use of appropriate transformers, switching, and control circuits. Static inverters have no moving parts and are used in a wide range of applications, from small switching power supplies in computers, to large electric utility high-voltage direct current applications that transport bulk power. Inverters are commonly used to supply AC power from DC sources such as solar panels or batteries.

               The electrical inverter is a high-power electronic oscillator. It is so named because early mechanical AC to DC converters were made to work in reverse, and thus were "inverted", to convert DC to AC.The inverter performs the opposite function of a rectifier.An inverter converts the DC electricity from sources such as batteries, solar panels, or fuel cells to AC electricity. The electricity can be at any required voltage; in particular it can operate AC equipment designed for mains operation, or rectified to produce DC at any desired voltage. An uninterruptible power supply (UPS) uses batteries and an inverter to supply AC power when main power is not available. When main power is restored, a rectifier is used to supply DC power to recharge the batteries.

         Electric vehicle drives

              Adjustable speed motor control inverters are currently used to power the traction motors in some electric and diesel-electric rail vehicles as well as some battery electric vehicles and hybrid electric highway vehicles such as the Toyota Prius. Various improvements in inverter technology are being developed specifically for electric vehicle applications.[2] In vehicles with regenerative braking, the inverter also takes power from the motor (now acting as a generator) and stores it in the batteries

   The general case

             A transformer allows AC power to be converted to any desired voltage, but at the same frequency. Inverters, plus rectifiers for DC, can be designed to convert from any voltage, AC or DC, to any other voltage, also AC or DC, at any desired frequency. The output power can never exceed the input power, but efficiencies can be high, with a small proportion of the power dissipated as waste heat

Circuit description

            In one simple inverter circuit, DC power is connected to a transformer through the centre tap of the primary winding. A switch is rapidly switched back and forth to allow current to flow back to the DC source following two alternate paths through one end of the primary winding and then the other. The alternation of the direction of current in the primary winding of the transformer produces alternating current (AC) in the secondary circuit.

             The electromechanical version of the switching device includes two stationary contacts and a spring supported moving contact. The spring holds the movable contact against one of the stationary contacts and an electromagnet pulls the movable contact to the opposite stationary contact. The current in the electromagnet is interrupted by the action of the switch so that the switch continually switches rapidly back and forth. This type of electromechanical inverter switch, called a vibrator or buzzer, was once used in vacuum tube automobile radios.As they became available with adequate power ratings, transistors and various other types of semiconductor switches have been incorporated into inverter circuit designs.

              The switch in the simple inverter described above, when not coupled to an output transformer, produces a square voltage waveform due to its simple off and on nature as opposed to the sinusoidal waveform that is the usual waveform of an AC power supply. The sine wave that has the same frequency as the original waveform is called the fundamental component. The other sine waves, called harmonics, that are included in the series have frequencies that are integral multiples of the fundamental frequency.

              The quality of the inverter output waveform can be expressed by using the Fourier analysis data to calculate the total harmonic distortion (THD). The total harmonic distortion is the square root of the sum of the squares of the harmonic voltages divided by the fundamental voltage: The quality of output waveform that is needed from an inverter depends on the characteristics of the connected load. Some loads need a nearly perfect sine wave voltage supply in order to work properly. Other loads may work quite well with a square wave voltage.

              H-bridge inverter circuit with transistor switches and antiparallel diodes

There are many different power circuit topologies and control strategies used in inverter designs. Different design approaches address various issues that may be more or less important depending on the way that the inverter is intended to be used.

              The issue of waveform quality can be addressed in many ways. Capacitors and inductors can be used to filter the waveform. If the design includes a transformer, filtering can be applied to the primary or the secondary side of the transformer or to both sides. Low-pass filters are applied to allow the fundamental component of the waveform to pass to the output while limiting the passage of the harmonic components. If the inverter is designed to provide power at a fixed frequency, a resonant filter can be used. For an adjustable frequency inverter, the filter must be tuned to a frequency that is above the maximum fundamental frequency.

               Since most loads contain inductance, feedback rectifiers or antiparallel diodes are often connected across each semiconductor switch to provide a path for the peak inductive load current when the switch is turned off. The antiparallel diodes are somewhat similar to the freewheeling diodes used in AC/DC converter circuits.Fourier analysis reveals that a waveform, like a square wave, that is antisymmetrical about the 180 degree point contains only odd harmonics, the 3rd, 5th, 7th etc. Waveforms that have steps of certain widths and heights eliminate or “cancel” additional harmonics. For example, by inserting a zero-voltage step between the positive and negative sections of the square-wave, all of the harmonics that are divisible by three can be eliminated. That leaves only the 5th, 7th, 11th, 13th etc. The required width of the steps is one third of the period for each of the positive and negative steps and one sixth of the period for each of the zero-voltage steps.

               

        Changing the square wave as described above is an example of pulse-width modulation (PWM). Modulating, or regulating the width of a square-wave pulse is often used as a method of regulating or adjusting an inverter's output voltage. When voltage control is not required, a fixed pulse width can be selected to reduce or eliminate selected harmonics. Harmonic elimination techniques are generally applied to the lowest harmonics because filtering is more effective at high frequencies than at low frequencies. Multiple pulse-width or carrier based PWM control schemes produce waveforms that are composed of many narrow pulses. The frequency represented by the number of narrow pulses per second is called the switching frequency or carrier frequency. These control schemes are often used in variable-frequency motor control inverters because they allow a wide range of output voltage and frequency adjustment while also improving the quality of the waveform.

            

             Multilevel inverters provide another approach to harmonic cancellation. Multilevel inverters provide an output waveform that exhibits multiple steps at several voltage levels. For example, it is possible to produce a more sinusoidal wave by having split-rail direct current inputs at two voltages, or positive and negative inputs with a central ground. By connecting the inverter output terminals in sequence between the positive rail and ground, the positive rail and the negative rail, the ground rail and the negative rail, then both to the ground rail, a stepped waveform is generated at the inverter output. This is an example of a three level inverter: the two voltages and ground.[3]

             3-phase inverter with wye connected load

      

              Three-phase inverters are used for variable-frequency drive applications and for high power applications such as HVDC power transmission. A basic three-phase inverter consists of three single-phase inverter switches each connected to one of the three load terminals. For the most basic control scheme, the operation of the three switches is coordinated so that one switch operates at each 60 degree point of the fundamental output waveform. This creates a line-to-line output waveform that has six steps. The six-step waveform has a zero-voltage step between the positive and negative sections of the square-wave such that the harmonics that are multiples of three are eliminated as described above. When carrier-based PWM techniques are applied to six-step waveforms, the basic overall shape, or envelope, of the waveform is retained so that the 3rd harmonic and its multiples are cancelled.

      Inverters and Applications

            Power inverters are devices which can convert electrical energy of DC form into that of AC. They come in all shapes and sizes, from low power functions such as powering a car radio to that of backing up a building in case of power outage. Inverters can come in many different varieties, differing in price, power, efficiency and purpose. The purpose of a DC/AC power inverter is typically to take DC power supplied by a battery, such as a 12 volt car battery, and transform it into a 120 ­­­/240 volt AC power source operating at 60 Hz, emulating the power available at an ordinary household electrical outlet. Figure 1 provides a idea of what a small power inverter looks like. Power inverters are used today for many tasks like powering appliances in a car such as cell phones, radios and televisions. They also come in handy for consumers who own camping vehicles, boats and at construction sites where an electric grid may not be as accessible to hook into. Inverters allow the user to provide AC power in areas where only batteries can be made available, allowing portability and freeing the user of long power

cords.                  On the market today are two different types of power inverters, modified sine wave and pure sine

wave generators. These inverters differ in their outputs, providing varying levels of efficiency and distortion that can affect electronic devices in different ways.A modified sine wave is similar to a square wave but instead has a “stepping” look to it that relates more in shape to a sine wave. This can be seen in Figure 2, which displays how a modified sine wave tries to emulate the sine wave itself. The waveform is easy to produce because it is just the product of switching between 3 values at set frequencies, thereby leaving out the more complicated circuitry needed for a pure sine wave. The modified sine wave inverter provides a cheap and easy solution to powering devices that need AC power. It does have some drawbacks as not all devices work properly on a modified sine wave, products such as computers and medical equipment are not resistant to the distortion of the signal and must be run off of a pure sine wave power source.

Figure 2: show a schematic diagram of an inverter