Correction system for regulating the power factor of an electrical network

Claim 1

A correction system for regulating the power factor of an electrical distribution network, comprising: means for sampling the potential difference of a distribution line of said network; means for sampling the current of said distribution line; means generating and storing first and second predetermined reference limits relating to desired power factors; means for measuring the phase difference based on the sampled potential difference and the sampled current; means for comparing the measured phase difference to said predetermined reference limits; means for monitoring the actual demand of said electrical distribution network; and means for controlling load actuating means connected to said distribution network in response to information obtained from said comparing means and information obtained from said monitoring means; said load actuation means being connected to capacitive loads whereby one or more capacitive loads may be added to the distribution network when the measured phase difference indicates a corresponding power factor which is below a first of said predetermined reference limits, and may be disconnected from the distribution network when the measured phase difference indicates a corresponding power factor which exceeds a second of said reference limits greater than said first limit; said controlling means being responsive to information obtained from said monitoring means to prevent capacitive loads from being added to the distribution network when the actual demand monitored by said monitoring means is below a predetermined demand value, independently of said information received from said comparing means.

Claim 5

A method of regulating the power factor of an electrical distribution network, comprising the steps of: sampling the potential difference of a distribution line of said network; sampling the current of said distribution line; generating and storing predetermined reference limits pertaining to a desired power factor; measuring the phase difference based on the sampled potential difference and the sampled current; comparing the measured phase difference to said predetermined reference limits; monitoring the actual demand of said distribution network; and controlling load actuating means connected to said distribution network in response to information obtained from the comparison of the measured phase difference to the predetermined reference limits and in response to information obtained from said monitoring; said controlling consisting of connecting one or more capacitive loads to the distribution network when the measured phase difference is below a first of said predetermined reference limits; and disconnecting capacitive loads from the distribution network when the measured phase difference exceeds a second of said reference limits greater than said first limit; said controlling further consisting of preventing capacitive loads to be connected when the actual demand monitored is below a predetermined demand value.

Claim 6

A method of regulating the power factor of an electrical distribution network, comprising the steps of: sampling the potential difference of a distribution line of said network; sampling the current of said distribution line; generating and storing predetermined reference limits pertaining to a desired power factor; measuring the phase difference based on the sampled potential difference and the sampled current; comparing the measured phase difference to said predetermined reference limits; monitoring the actual demand of said distribution network; and controlling load actuating means connected to said distribution network in response to information obtained from the comparison of the measured phase difference to the predetermined reference limits and in response to information obtained from said monitoring; said controlling consisting of connecting one or more capacitive loads to the distribution network when the measured phase difference is below a first of said predetermined reference limits; and disconnecting capacitive loads from the distribution network when the measured phase difference exceeds a second of said reference limits greater than said first limit; said controlling further consisting of preventing capacitive loads to be connected when the actual demand monitored is below a predetermined demand value.