Abstract: The fully-automatic closed-loop detection method includes: comparing a SCD file of a to-be-tested substation with a device-type data template file, so as to determine whether configuration information about the to-be-tested substation is correct; when the configuration information about the to-be-tested substation is correct, parsing the SCD file of the to-be-tested substation and generating a SSD topological diagram of the to-be-tested substation; and acquiring a testing item from a predetermined testing item library in accordance with the SSD topological diagram of the to-be-tested substation, generating a testing scheme for the to-be-tested substation, performing a testing operation and outputting a testing result.

Abstract: The fully-automatic closed-loop detection method includes: comparing a SCD file of a to-be-tested substation with a device-type data template file, so as to determine whether configuration information about the to-be-tested substation is correct; when the configuration information about the to-be-tested substation is correct, parsing the SCD file of the to-be-tested substation and generating a SSD topological diagram of the to-be-tested substation; and acquiring a testing item from a predetermined testing item library in accordance with the SSD topological diagram of the to-be-tested substation, generating a testing scheme for the to-be-tested substation, performing a testing operation and outputting a testing result.

Abstract: A system for staring a large-scale power load in a micro grid comprises a PCC grid connection switch, a micro grid alternating-current bus, an active power filter (APF), an energy storage inverter, an energy storage battery, a current-limiting resistor R, contactors K1-K3, a time relay KT, a power supply relay board, a micro grid maser control system, a frequency converter rectifying circuit, a frequency converter filter circuit, and a frequency converter inverter circuit. There are the advantages: an output torque of a power load can be effectively improved by using a variable frequency starting apparatus, and a starting current is also small; the provided method can effectively reduce a harmonic current when a variable frequency starting apparatus starts a power load, the phenomenon that two power sources supply power on a direct-current side of the variable frequency starting apparatus at the same time is avoided, thereby improving the stability and the economy of a micro grid.

Abstract: A system for staring a large-scale power load in a micro grid comprises a PCC grid connection switch, a micro grid alternating-current bus, an active power filter (APF), an energy storage inverter, an energy storage battery, a current-limiting resistor R, contactors K1-K3, a time relay KT, a power supply relay board, a micro grid maser control system, a frequency converter rectifying circuit, a frequency converter filter circuit, and a frequency converter inverter circuit. There are the advantages: an output torque of a power load can be effectively improved by using a variable frequency starting apparatus, and a starting current is also small; the provided method can effectively reduce a harmonic current when a variable frequency starting apparatus starts a power load, the phenomenon that two power sources supply power on a direct-current side of the variable frequency starting apparatus at the same time is avoided, thereby improving the stability and the economy of a micro grid.

Abstract: A method for calculating a primary time constant of a power grid. It comprises the steps of: establishing an electromechanical transient model of the power grid using the widely used power system analysis software package (PSASP) according to the actual power grid parameters and network topology; establishing an electromagnetic transient model under PASAP using the actual power grid parameters for a site which requires the calculation of the primary time constant of the power grid, and setting a ground short circuit fault at the site; obtaining a transient short circuit current of the short circuit point of the power grid using a hybrid simulation method of the electromechanical and electromagnetic transient models; filtering out a periodic component in the transient short circuit current to obtain a non-periodic component attenuated with time, and finding the attenuation time constant of the non-periodic component which is the primary time constant of the power grid.

Abstract: A method for calculating a primary time constant of a power grid. It comprises the steps of: establishing an electromechanical transient model of the power grid using the widely used power system analysis software package (PSASP) according to the actual power grid parameters and network topology; establishing an electromagnetic transient model under PASAP using the actual power grid parameters for a site which requires the calculation of the primary time constant of the power grid, and setting a ground short circuit fault at the site; obtaining a transient short circuit current of the short circuit point of the power grid using a hybrid simulation method of the electromechanical and electromagnetic transient models; filtering out a periodic component in the transient short circuit current to obtain a non-periodic component attenuated with time, and finding the attenuation time constant of the non-periodic component which is the primary time constant of the power grid.