Switching between modes is possible by using the algorithm in an automatic mode or by the operator's command or by the programmed schedule. It can be controlled from the ESS control console or remotely by using the GSM-modem or Ethernet.
Standby mode:
ESS does not consume and does not output electricity to the power grid with the exception of the consumption for internal power supply of power modules and control console.
Energy storage mode.
ESS switches to the energy storage mode if there is no need for a power output. When the electrical parameters are within the working range, ESS charges the batteries. The operator sets the value of power that is consumed from the power grid.
Mode of transfer of the electric power to the power grid.
ESS goes to the mode of conversion DC to AC. AC voltage is synchronized in frequency, phase and instantaneous value of the voltage to the mains voltage. Output current of ESS is limited within specifications.
Mode of reactive power compensation and filtering
ESS measures the mains voltage and the current consumed by the load and synthesizes such a form of output current that allows to compensate for the reactive component of power and suppress the higher harmonics of the load current. Stored in the batteries energy is not consumed.
Adding power mode.
ESS switches to the mode of power supply of load without output of energy to the power grid. Battery DC voltage is converted into AC voltage which is synchronized in frequency, phase and instantaneous value of the voltage to the mains voltage. In this case the output current of ESS is limited by consumption of the current of load.
In this mode, ESS measures the level of power consumed by the load. If it exceeds a predetermined threshold of consumption, ESS begins to add power corresponding to the difference between the predetermined threshold of consumption and consumed by the load.
Mode of autonomous power supply of loading
ESS switches to the mode of off-line power supply of load with unplugging. ESS control system makes control of battery voltage and turns off the power output at low battery voltage to prevent deep discharge of batteries. In this case load will be plugged back to the mains, and ESS will switches to energy savings mode (if different algorithm of work of ESS is not specified by the operator).
Mode of balancing of interphase current (optionally)
When the load consumes a current from the power grid uneven (bias of power), ESS switches to the balancing mode taking power from the underloaded phases and giving it to the overloaded phases. In this case the power equipment works in a steady state and also the phase voltages are automatically aligned. In this mode, battery power is not used
Combined modes
Energy storage mode can be combined with reactive power compensation mode, if the required for charging the battery current is less than the maximum consumed current by ESS.
Mode of transfer of the electric power to the power grid can be combined with reactive power compensation mode, if the required for power grid current is less than the maximum consumed current by ESS.
Adding power mode can be combined with reactive power compensation mode, if the current required for power grid is less than the maximum consumed current by ESS.
Mode of balancing of interphase current can be combined with reactive power compensation mode when the load current does not exceed the threshold, after which the adding power mode begins. |
In the context of the deficit of electricity, of the power grids congestion and the inability of capital construction of new power lines or connection of new generators, Energy Storage System (ESS) allows locally solve the problem of power supply without significant financial expenses.
