Industrial generator failures: what you need to know

Industrial generators are responsible for supplying industries with their electricity needs. As such, they are used in production flows that demand more energy than the traditional distribution network can offer or reach. These assets work in a similar way to the generators used to supply residential energy, but they have a much greater energy production capacity, as they power entire industrial plants. In addition to generating energy, the function of these assets is also to distribute it in a stable and continuous manner.

These assets are considered highly critical, as their operation is fundamental to powering the entire plant. Without them, key processes in the production flow cannot take place. In addition, industrial generators can run on different fuels, such as gasoline, diesel and gas.

Learn more about these assets and their most common failure modes in the following text. 

Types of industrial generators

Direct current generators  

A direct current electrical generator (DC), also called a dynamo, is an electrical machine that converts mechanical energy (water, air, etc.) into electrical energy in the form of direct current, i.e. the current generated does not change over time. In terms of construction, the DC generator is more complex than other types due to the presence of components such as commutators and collector rings. 

Alternating current generators

This type of generator also converts mechanical energy into electrical energy, but in the form of alternating current (AC), i.e. the current varies over time. The design of an AC generator is relatively simple and economical, usually containing a fixed coil and a moving magnet. These generators use collector rings, which provide a smooth and efficient surface for the brushes, resulting in low maintenance and high reliability.

Synchronous generators

Type of AC generator in which the frequency of the electric current generated is synchronized with the frequency of rotation of the motor. A characteristic of this type of generator is that the frequency of the alternating current remains fixed, no matter what load the asset is supplying. In addition, this type of generator can be single-phase or three-phase and can be used to generate electricity in large or small systems.

Asynchronous generators

Similarly to synchronous generators, asynchronous generators are also a type of AC generator. Among the main advantages of this equipment are the absence of mechanical contacts on the rotor, reducing maintenance due to wear, and the independence of synchronism with the rotor speed, which makes it widely used in applications such as wind farms. 

Industrial generator components

Rotor: also called the armature is the moving part of the generator where the current is induced due to the relative movement between the magnetic field and the wire windings.

Stator: is the fixed part of the generator and generates the magnetic field needed to induce current. It can be created by permanent magnets or electromagnets.

Brushes: They transfer the current generated in the rotor to the circuit outside the generator. They are also used to maintain electrical contact with rotating components.

Rotor core: It increases the efficiency of magnetic induction and reduces energy losses due to eddy currents.

Rotor windings: Wound copper wires that generate the electrical voltage as the armature core rotates within the magnetic field.

Cooling system: The function of this component is to prevent the equipment from overheating. This system consists of radiators, fans and water pumps that dissipate heat and cool the generator. 

Main failure modes in industrial generators

Industrial generator failures can be catastrophic. It is not uncommon for fires or explosions in industrial plants to be caused by faults in electrical systems and generators. Especially in environments with explosive atmospheres, sparks, overheating and other factors related to the condition of electrical installations.

Here are some common failure modes in industrial generators:

Rotor insulation damage

This refers to damage to the insulation layer covering the rotor wires or turns, or the earth connection. It can result in internal short circuits, overheating and electrical faults, thus compromising the generator’s performance and increasing the risk of catastrophic failures.  

Stator insulation damage

Damage to the insulation layer of the stator wires or turns, or to the earth connection. Similar to damage to rotor insulation, this can cause short circuits, overheating and degradation of electrical performance. It can also lead to the generator being shut down for repairs.

Bearing failures

Wear, degradation or complete failure of the bearings that support the generator rotor. This type of failure mode can cause excessive vibrations, abnormal noise and, eventually, rotor locking. If not detected and corrected quickly, it can lead to further damage to the rotor and stator.

Faulty rotor connections

Damage or breakage to the electrical connections linking the rotor to the rest of the generator circuit. As a result, there can be interruptions in the transmission of electricity, loss of efficiency and excessive heating, which can lead to intermittent failures or the generator stopping completely. 

Cooling system failures

Problems in the cooling system, including leaks, blockages or failures in the cooling components can lead to the generator overheating and eventually require emergency shutdowns to prevent further damage. 

Curtos nos Anéis Coletores

Electrical faults in the collector rings that transfer current into and out of the rotor. This can cause sparking, heating and accelerated wear of the brushes and the collector rings themselves, resulting in frequent maintenance and possible generator downtime. 

Problems with circuit breakers

The main symptoms of problems with circuit breakers are loss of efficiency, overloading, overheating and so on. To prevent these components from failing, they need to be monitored frequently.  

Battery faults

In industrial generators, the battery can also be a frequent source of failure. Discharging, the formation of sulphates on the plates and improper operating conditions can compromise the functioning of this component and damage the asset.  

Solution for monitoring industrial generators

Dynamox has a solution designed exclusively for monitoring voltage and current in industrial assets. The Enging device monitors the health of machinery and identifies early failures. This makes it possible to plan maintenance actions and see windows for improvement based on accurate analysis. In addition, it is possible to drastically reduce the costs of repairing or replacing electric motors.

Current and voltage monitoring makes it possible to track and analyze power, voltage and current information. This allows for a detailed diagnosis of the asset’s state of health. This monitoring, when carried out periodically, also allows the maintenance manager to identify points for improvement. This is because this data reveals current leaks, instabilities, distortions and electrical surges. It is on the basis of this information that a plan is developed to guarantee the energy efficiency of the assets.

Enging’s solution for electrical assets monitors online and in real time, guaranteeing reliable data that is always up to date. In other words, all monitoring is done using intelligent algorithms and there is no need for data history and a learning period.

To monitor industrial generators, the Enging Solution uses a mathematical model that allows the calculation of the transformer’s internal parameters, excitation current analysis, short-circuit inductance, OLTC dynamic impedance, harmonic component analysis and inrush current analysis.

All this data enables real-time monitoring of the asset’s operation and also makes it possible to anticipate possible failures in order to avoid them, without the need for unplanned shutdowns that could compromise the entire operation of the plant.

Do you want to increase the reliability and availability of industrial generators? Discover the Dynamox Solution! Contact us to find out more.