EM Energy Solution’s technology is based on the fundamentals of electromagnetism, and the unit reacts to electrical noise and imbalance with the speed of the electromagnetic field.
The AVE’s primary purpose is to stabilize the voltage with reference to ground, and by doing so, prove highly beneficial against well-known power quality problems.
The unit’s main components are 3 single-phase variable isolation transformers that have a wye connected primary with neutral connected to ground, giving it a fixed reference to control the voltage. The secondary side is connected in delta in series with a purely resistive load.
With this setup, any voltage imbalance induces a current in the secondary side circuit, which in turn feeds energy back to the low voltage phase from the high voltage phases together with dissipating excess energy in the resistor. The variable isolation transformers make it possible to optimize the flow of energy in such a way that voltage imbalances are kept within 3 percent.
In an ideal world where you have a pure 3-phase supply consisting of only the fundamental frequency without any harmonic components and where each phase has the same amplitude and 120-degree phase shift, the system is balanced with respect to AVE primary side ground reference. This balance means there is no induced current in the transformers secondary side, and the AVE does not consume or transfer energy between the phases.
There is no such thing as an ideal world, meaning there will always be some amount of imbalance in a 3-phase supply.
When the unit is connected, and transformers energized, it is ready to counteract any kind of power quality issue that distorts the 3-phase voltage supply. Any kind of unsynchronized imbalance on the voltages is detected on the transformer`s primary side, and the unit starts to counteract it.
The amount of current induced in the secondary side is based on the amount of voltage imbalance on the AVEs primary side. If one applies the well-known rule of Kirchhoff’s fundamental voltage law, which states that the algebraic sum of all the voltages around any closed loop in a circuit is equal to zero. The voltage drop across the impedance in the circuit is determined by the vectorial sum of the voltages in the transformer`s secondary side, which again can be used to calculate the current in the circuit.
Knowing both the secondary side current and the voltage drop, energy transfer can easily be calculated.
One would believe that balancing voltages between phases require large amounts of energy, but this is not the reality. As an example, we can take a look at one of the tests we did at the Power Network Demonstration Centre in Scotland. We saw that our unit only consumed 18.6mA in the secondary side circuit to correct a voltage imbalance of 12%. The test was done by adding a single-phase load on to a transformer operating with a base load of 63% of transformer capacity. Detailed information about this test is available under Downloads on our website.
In any 3-phase distribution system, there will always be stray capacitance causing leak current to ground. In situations where AVE is not installed, this energy goes to waste and cause additional costs in terms of higher electricity bills.
The AVE prove highly beneficial against capacitance leak current to ground, in the way that it uses this energy to balance and optimize the power quality instead of wasting it. This gives substantial savings in terms of reduced electricity bills.
When it comes to voltage harmonics, this is high-frequency voltage imbalances, and since the AVE reacts with the speed of the electromagnetic field, it can suppress zero-sequence voltage harmonics up to very high frequency ranges.
For transient surges such as voltage spikes caused by lightning strikes, this detects as a huge voltage imbalance, which again causes the unit to react more. The higher the voltage imbalance, the more the AVE counteracts it. The problem with surge protection devices is that they are to slow to prevent damaging voltage levels entering into the system. Because of the speed of the AVE, it can suppress the transients before they reach damaging levels, thus protecting all downstream equipment.
AVE is designed to be connected in parallel on the transformer`s secondary side and as close to the transformer as possible. This ensures optimal protection of all downstream equipment connected to the same distribution line.