Grid Codes

The increasing use of renewable power sources for power generation brings new demands to system operators and control systems to ensure safe, secure and economical functioning of an electricity network. These demands are reflected in new connection requirements for power generation control systems. These requirements are typically defined by the local transmission network operator (TNO) and are unique for each country, however there are commonalities across the world.

ComAp has developed comprehensive and flexible solutions for every application including paralleling gen-sets, CHP and others. Our products meet or exceed the local grid codes or standards from countries around the world and are constantly being reviewed and updated to ensure they stay up to date with any changes.

What are Grid Codes?

Grid Codes are technical specifications which defines the parameters a facility connected to a public electric network has to meet to ensure safe, secure and economic proper functioning of the electric system. The facility can be an power generation plant, a solar farm, or any other grid connected source.

Our Grid Code Features

We achieve the best service thanks to following the latest Grid Code regulations.

Operating area Dynamic network support Active power response to frequency Reactive power control

Operating area

There are defined minimal requirements to gen-set's operating areas in terms of voltage and frequency levels. These areas define where must be gen-set capable of running permanently and areas, where is a minimal operating time. It is not allowed to disconnect gen-set sooner than the time defined in this area.

Dynamic network support

The Voltage Ride Through (VRT) function supports the grid during short, but significant, voltage drops or peaks. There is a defined area where it is not allowed to disconnect a grid-connected gen-set. The area is defined by voltage level and time. The VRT function can be split into two types: Low Voltage Right Through (LVRT), which supports the grid during voltage drops and Over Voltage Ride Through (OVRT), which supports grid during peaks.

Some countries require both LVRT and OVRT, and some require only one – ComAp’s products support both.

Active power response to frequency

Frequency is one of the most important indicators of power in the grid. If the frequency is falling, there is a lack of active power in the network. If it is rising, more active power is being generated than is necessary. This might be caused by renewable power sources depending on weather such as a solar power plant or wind farm. It is reflected in this requirement where a gen-set's reaction is defined because of frequency fluctuation. Details might be different in different countries, but in principle the requirement is to increase the gen-set's power on under-frequency and reduce gen-set's power on over-frequency.

Reactive power control

Reactive power is an important part of the grid and its amount might be indicated by voltage level. There are several new functions related to reactive power control and system stability. The requirement of particular functionalities is given by local transmission network operator.

Alternator Operating Area

The reactive power is an important part of grid and its amount might be indicated by voltage level. There are several new functions related to reactive power control and system stability. The requirement of particular functionalities is given by local transmission network operator.

There is a defined generator operating area of P/Q ratio and implement maximal apparent power (Smax). This parameter is important especially in case of undervoltage when there is higher demand to reactive power. In that case might be actual current higher than nominal current, and control system will decrease its actual power to gain required reactive power, but not exceed maximal apparent power Smax.

Reactive Power and Power Factor Control Modes

Depending on local regulations some new reactive power and power factor control modes may be required:

Fixed PF
Fixed Q
Qref=f(Ulim)
PF=f(Pm)
Q=f(Um)

These features might not be required in every country. It is always dependent on local transmission network operators, local regulations and grid codes.