JP2012251817A5

JP2012251817A5 -

Info

Publication number: JP2012251817A5
Application number: JP2011123286A
Authority: JP
Filing date: 2011-06-01
Publication date: 2014-01-16
Anticipated expiration: 2031-06-01

Claims

An insulation deterioration monitoring system for monitoring insulation deterioration of a ground insulation resistance based on the voltage, frequency, and zero-phase current of an AC circuit connected to an inductive load, the monitoring means for monitoring the control state of the inductive load And an insulation deterioration monitoring system for monitoring insulation deterioration by a calculation means for calculating a leakage current corresponding to a ground insulation resistance based on the control state of the inductive load detected by the monitoring means.

Characterized by monitoring the insulation deterioration by the first computing means controlling the state of said inductive load which is detected by said monitoring means you calculating the leakage current of the ground insulation resistance component when a stable state The insulation deterioration monitoring system according to claim 1.

The voltage of each time the drive frequency is different of the inductive load, frequency, based on the zero-phase current, and wherein monitoring the insulation deterioration by the second arithmetic means you calculating the leakage current of the ground insulation resistance of The insulation deterioration monitoring system according to claim 1.

If the control state of the inductive load which is detected by said monitoring means is a stable state monitors insulation deterioration by the first arithmetic means you calculating the leakage current of the ground insulation resistance component, the inductive load claims that may drive frequency is unstable control state is different the inductive load is characterized by monitoring the insulation deterioration by the second arithmetic means you calculating the leakage current of the ground insulation resistance component Item 2. The insulation deterioration monitoring system according to Item 1.

Voltages applied to the plural-phase cable, the frequency, the leakage current or al various electrical quantity of a plurality of phases paths measurement or insulation deterioration monitoring system for external output, and frequency detecting means for detecting a frequency of a multiple-phase cable, said plurality voltage detecting means for detecting a voltage of-phase circuit, a ground fault detector for detecting the leakage current from the output signal of the zero-phase current transformer, electrical quantity of the secondary-side load of the load driving device from the input frequency and voltage There a leakage current (Ior) calculation instruction unit determines that can be calculated, the leakage current (Ior) calculation instruction unit receives an instruction from said frequency detecting means and said voltage detecting means and the frequency detection value by said leakage detection means The leakage current (Ior) calculation unit that calculates the leakage current (Ior) due to ground insulation resistance from the detected voltage value and the detected leakage value, and the reference voltage value based on the zero-phase current fluctuation due to the load voltage fluctuation External voltage value setting means for calculation, a data storage means for storing the result of the above operation, the stored data output means for data transfer to the outside by the communication data stored in the data storing means, the electric leakage state by the result of the calculation An insulation monitoring system comprising alarm output means for outputting to

The leakage current (Ior) calculation instruction unit, the frequency by the frequency detecting means obtained by high speed sampling, when the value of the frequency is also the properly several cycles a match is determined to be equivalent, the leakage current (Ior) calculated parts to give an indication of the operation start of the leakage current due to the ground insulation resistance (Ior), for converting the voltage value as a reference the variation in the zero-phase current according to the voltage variation of the load, high-speed voltage by said voltage detecting means insulation deterioration monitoring system according to claim 5, characterized in that it comprises means for providing to the leakage current (Ior) calculating unit voltage value when acquired by the sampling, giving an indication of the operational start.

The leakage current (Ior) calculation instruction unit, the frequency by the frequency detecting means obtained by high speed sampling, when the value of the frequency is determined to be the properly several cycles a match is equivalent, the leakage current (Ior) as means for giving an instruction of operation start of the leakage current to the calculation unit by the ground insulation resistance (Ior), compares the set value of the frequency state and the frequency of the load, both the leakage current when the equivalent (Ior) 6. The insulation deterioration monitoring system according to claim 5, further comprising means for giving a calculation start instruction.

The leakage current (Ior) calculation instruction unit, the frequency by the frequency detecting means obtained by high speed sampling, when the value of the frequency is determined to be the properly several cycles a match is equivalent, the leakage current (Ior) as means for giving an instruction of operation start of the leakage current (Ior) to the calculation unit by the ground insulation resistance, insulation according to claim 5, characterized in that it comprises processing means for automatically determining from the frequency state of the load Deterioration monitoring system.

The leakage current (Ior) calculation unit extracts the first frequency component as the control frequency of the load and the seventh harmonic component of the first frequency component as the control frequency of the load as the second frequency component. and, the first frequency component as the control frequency of the load is selected at fixed intervals along the high frequency band of the harmonic content when calculated in response to an instruction from the leakage current (Ior) calculation instruction unit above insulation deterioration monitoring system according to claim 5 or claim 6, wherein the calculating leakage current (Ior) leakage calculation unit mode current (Ior), and outputs to the data storage means.

The leakage current (Ior) calculation unit extracts a first frequency component and a second frequency component having different frequency bands as the control frequency of the load, and the first frequency component and the above as a control frequency of the load. The second frequency component is a frequency having a large difference in frequency between the first frequency component and the second frequency component when calculated by receiving an instruction from the leakage current (Ior) calculation instruction unit. The leakage current (Ior) calculating section cancels the leakage current due to the ground capacitance and calculates the leakage current (Ior) due to the ground insulation resistance, and outputs the leakage current to the data storage means. The insulation deterioration monitoring system according to claim 5 or 6.

The voltage value setting means determines a voltage setting value for converting the fluctuation of the zero-phase current due to the voltage fluctuation of the load into a reference voltage value, and the leakage current (Ior) calculation unit by the voltage setting value The insulation deterioration monitoring system according to claim 5 or 6, wherein the insulation deterioration monitoring system is converted into a reference voltage value.

The leakage current (Ior) calculation unit always extracts a first frequency component and a second frequency component having different frequency bands as the control frequency of the load, and the first frequency as the control frequency of the load. The component and the second frequency component have a certain frequency with a large difference in frequency between the first frequency component and the second frequency component when calculated in response to an instruction from the leakage current (Ior) calculation instruction unit. selected in the period of calculating the leakage current due to ground insulation resistance (Ior) to offset the leakage current due to the earth capacitance in the leakage current (Ior) calculating unit, the frequency variation such potato properly of the load less case, the first frequency component as the control frequency above Symbol load, the seventh order harmonic component of the first frequency component as the control frequency of the load extracted as a second frequency component, of the load As the control frequency, the first frequency component is selected by selecting a frequency band having a high harmonic content when calculated in response to an instruction from the leakage current (Ior) calculation instruction unit, and the leakage current (Ior). by calculating the leakage current (Ior) calculation unit, according to claim 5, characterized in that to enable the calculation of the leakage current (Ior) by the ground insulation resistance without depending on the control characteristics of the load Insulation deterioration monitoring system.