Power systems

Modern power supply systems are required to regulate, convert and distribute electrical energy and also contribute to the continuous supply of various AC and DC voltages. Designed for normal operation of radio equipment, computers and personal computers, alarm and security devices.

All power systems are divided into 3 categories:

• Guaranteed power supply system;

• continuous power supply system;

• Backup power system.

Guaranteed power systems

They must provide a full guarantee of power supply to the connected devices, automatic start, automatic transfer of load from the diesel generator to the external power network and vice versa, issuing an alarm if an emergency situation has occurred with the equipment.

Depending on your power supply requirements, you can use different methods to build circuits. Consider a guaranteed power supply scheme.

In the event that only a diesel generator acts as a backup power source in the facility, this is the guaranteed power supply scheme.Consumers who receive electricity from a diesel generator in the event of a power outage are called guaranteed energy consumers.

It is most recommended to use this scheme when there are frequent voltage failures in the main network, and there are also no category I users who need the normal operation of the power supply without disturbing the voltage sine wave.

In order to create a scheme for guaranteed supply of the facility, the following requirements should be taken into account:

• Diesel generator sets must be equipped with an MTBF of more than 40,000 hours;

• It is not recommended to load a diesel generator with a load for a long time whose capacity is less than 50 percent. A load below 30 percent results in the seller voiding the equipment warranty;

• The period of accepting the load and starting the emergency mode from the standby mode must be less than 9 seconds;

• Ensuring the ability to carry out repair work and maintenance of the unit without interruptions in the operation of the power supply system;

• Provision of remote control of a diesel generator;

• Disabling the possibility of parallel operation of the block with external power supply systems.

Uninterruptible power supply systems nRequired for:

• Uninterrupted power supply to consumers (there should be no interruption of the sine wave);

• Creating an output voltage with a pure sinusoidal shape;

• Ensuring high efficiency;

• Ensuring compatibility with diesel generators, power reserve factor less than 1.3;

• Providing maximum protection against surges, surges, surges;

• Possible parallel connection of several power supplies;

• Providing independent load support for 20 minutes;

• Continuous load switching;

• galvanic isolation of the output and input circuits;

• Remote monitoring and control of system parameters of uninterruptible power supplies.

Electric circuit for uninterruptible power supply — This is a scheme in which only an uninterruptible power supply is used as a backup source. Consumers who receive energy from sources when the mains voltage has disappeared are called uninterruptible power consumers.

It is more expedient to use this scheme when the disappearance of the mains voltage occurs rarely and for a short time.

To create this scheme, you need to consider the requirements:

• Average period of operation over 10 years;

• Avoid overloading the neutral cables of the network and terminating the transformer substation;

• Repairs and maintenance must be carried out without disrupting the operation of the system;

• Creation of remote work management;

• Proper completion of all technological processes.

It is also possible to use a combined guaranteed and uninterruptible power supply scheme. The scheme for increased reliability with the use of guaranteed and uninterruptible power supply has both a diesel generator and an uninterruptible power supply.

When the mains voltage disappears, a signal to turn it on appears on the diesel generator. During power-on (5-15 seconds), the receivers of the guaranteed power supply are de-energized for a short period of time.Restoration of power to users with guaranteed power to normal frequency occurs at the output of the diesel generator.

During the diesel generator start-up period, the uninterruptible power goes to the battery, as a result of which the uninterruptible power consumers are powered by the source batteries for the time required to start the diesel generator. Therefore, the power supply to consumers is carried out without disturbing the voltage sine wave.

When the external network voltage is restored during the switching of consumers from the diesel generator to the external network, the recipients of the guaranteed power supply are without voltage for a short period. Therefore, power supply to consumers is carried out in normal mode. After a complete shutdown, the diesel generator remains in standby mode.

Power from a diesel generator is possible for a certain period of time, which is determined by the fuel supply and its consumption, as well as the possible refueling of the diesel generator during operation. This combined circuit is best used in equipment that requires increased reliable power supply.

Back-up power systems allow you to avoid the troubles associated with power outages. The main positive factors of a modern backup power system:

• Power outages are not scary;

• It is possible to add capacity in case of its shortage;

• Saving electricity.

The system includes an inverter and a battery.

Inverter — responsible for charging the batteries (possibly in case there is a built-in charger), converts the current from direct to alternating current. It is also called an uninterruptible power supply device, the settings of which control all the main parameters of the system.

Are Rechargeable Batteries Keepers of Electricity? When there is a power failure from the central grid, the power is disconnected from these batteries. It is also possible to add additional power from them to the consumption at any time.

At any time, you can add an alternative power source to the backup power system and, as a result, get an autonomous power system, which makes it possible not to use the central power supply.