Energy storage system and operating method thereof

An operating method of an energy storage system, wherein the energy storage system is configured to provide power regulation for a power grid with a maximum value of the power regulation being a contracted capacity,

• when an operating frequency of the power grid is greater than or equal to a first frequency and less than or equal to a second frequency, a regulation ratio of the power regulation of the energy storage system is greater than or equal to a first input boundary value and less than or equal to a first output boundary value;
• when the operating frequency of the power grid is greater than or equal to a third frequency and less than or equal to the first frequency, the regulation ratio of the power regulation of the energy storage system is greater than or equal to the first input boundary value and less than or equal to a second output boundary value;
• when the operating frequency decreases from the first frequency to the third frequency, a plurality of first upper limits of the regulation ratio, which correspond to a plurality of first operating frequencies decreasing from the first frequency to the third frequency, increase from the first output boundary value to the second output boundary value correspondingly, and a plurality of first lower limits of the regulation ratio, which correspond to the plurality of first operating frequencies decreasing from the first frequency to the third frequency, increase from the first input boundary value to the second output boundary value correspondingly;
• when the operating frequency of the power grid is greater than or equal to the second frequency and less than or equal to a fourth frequency, the regulation ratio of the power regulation of the energy storage system is greater than or equal to a second input boundary value and less than or equal to the first output boundary value;
• when the operating frequency increases from the second frequency to the fourth frequency, a plurality of second upper limits of the regulation ratio, which correspond to a plurality of second operating frequencies increasing from the second frequency to the fourth frequency, decrease from the first output boundary value to the second input boundary value correspondingly, and a plurality of second lower limits of the regulation ratio, which correspond to the plurality of second operating frequencies increasing from the second frequency to the fourth frequency, decrease from the first input boundary value to the second input boundary value correspondingly;
• wherein the energy storage system comprises an energy storage unit, a measurement unit and a control unit, the energy storage unit is configured to store and provide power, the measurement unit is configured to measure the operating frequency of the power grid, and the control unit is coupled to the measurement unit and the energy storage unit and is configured to receive the operating frequency of the power grid measured by the measurement unit;
• when a state of charge of the energy storage unit is greater than a first charge level, the energy storage unit is in a normal charge state;
• when the state of charge of the energy storage unit is less than the first charge level, the energy storage unit is in a low charge state;
• when the control unit configures the regulation ratio of the power regulation of the energy storage system to be greater than 0, the control unit configures the energy storage unit to supply the power to the power grid with the regulation ratio of the contracted capacity;
• when the control unit configures the regulation ratio of the power regulation of the energy storage system to be less than 0, the control unit configures the energy storage unit to be charged by the power grid with the regulation ratio of the contracted capacity;
• wherein the operating method comprises:
• when the operating frequency of the power grid measured by the measurement unit is greater than or equal to a first frequency boundary value and less than or equal to a second frequency boundary value, configuring the control unit to configure the regulation ratio of the power regulation to be a first operating ratio, wherein the first operating ratio is less than or equal to 0 and greater than or equal to the first input boundary value;
• wherein the first frequency boundary value is less than the first frequency, and/or the second frequency boundary value is greater than the second frequency.