The noise from the internally generated transients (switching noise) adversely affects the system’s performance. The effects cause protection and performance issues to the system, costing thousands of dollars to the facility. Here are some of the examples of adverse effects from the higher-order harmonics from the switching transients.
- Switching noise increases the eddy current and hysteresis losses in the magnetic material, resulting in increased heat and inefficient operation of the motor. The noise ultimately results in slip losses, vibrations, and insulation failures.
- Switching noise malfunctions the behavior of electronics in a sensitive load, such as fluorescent and LED lighting, resulting in premature failures.
- The noise feeding to IC’s results in improper functioning of the timing circuits, causing improper switching of MOSFETs and IGBTs, resulting in erratic behavior and random load failure.
- Transients and noise combined to degrade the contacting surfaces of the switches, disconnects, and circuit breakers. Intense transient activity can produce “nuisance tripping” of breakers by heating the breaker and “fooling” it into reacting to a non-existent current demand
- The noise increases the skin effect on the wire. The flow of electrons tends to be on the skin of the wire, leaving a hollow cylinder on the cross-section of the wire for no use. This phenomenon limits the wire’s amperage (load) capacity and therefore becomes less efficient to carry currents. The wire eventually runs hotter, with its insulation prone to higher temperatures. The noise increases the system’s impedance, and thus the ohmic losses (i2R losses) increase, causing the equipment to run at a hot temperature. For every 10C rise in temperature, the equipment loses its life by half. Therefore, the noise causes premature death of electrical loads.
There are many other adverse effects of higher-order harmonics in the system. These are just a few.