Substation automatic control system

• US 8,494,684 B2
• Filed: 07/09/2012
• Issued: 07/23/2013
• Est. Priority Date: 01/25/2010
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Saotome, Hirotoshi, Yamamori, Wataru, Tomaru, Koichi
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): Booker, Kelvin
• Application Number:
  US13/544,283
• Publication Number:
  US 20120274303A1
• Time in Patent Office: 379 Days
• Field of Search: None
• US Class Current: 700/286
• CPC Class Codes: G06F 1/14 Time supervision arrangements, e.g. real time clock
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: H02H 3/006 Calibration or setting of parameters
• CPC Class Codes: H02H 3/40 responsive to ratio of voltage and current
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 3/12 for adjusting voltage in ac networks by changing a characteristic of the network load
• CPC Class Codes: H02J 3/1878 using tap changing or phase shifting transformers
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: Y02E 40/30 Reactive power compensation
• CPC Class Codes: Y04S 10/50 Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications

Abstract

According to one embodiment, there is provided a substation automatic control system. An automatic power adjusting apparatus activates an automatic voltage adjusting apparatus when a phase tap is controlled. The automatic voltage adjusting apparatus activates the automatic power adjusting apparatus when a voltage tap is controlled. The automatic power adjusting apparatus suppresses the effective power on a transmission line to the value smaller than the prescribed value while the automatic voltage adjusting apparatus is performing an automatic control, thereby maintaining transmission-side system voltage within a tolerant system voltage range.

Claims

1. A substation automatic control system, comprising:

a voltage/effective-power adjusting transformer, which is installed between a main bus of a substation and a transmission line, and which includes a voltage tap and a phase tap;

an automatic power adjusting apparatus configured to obtain electrical parameters of the transmission line via an instrument transformer, to calculate an effective power of the transmission line, and to output a phase-tap control command to the phase tap of the voltage/effective-power adjusting transformer, to suppress the effective power to a value smaller than a predetermined value when the effective power exceeds the predetermined value; and

an automatic voltage adjusting apparatus configured to obtain the electrical parameters of the transmission line via the instrument transformer, to calculate a system voltage of the transmission line, and to output a voltage-tap control command to the voltage tap of the voltage/effective-power adjusting transformer, to make the system voltage fall within a predetermined range,

wherein the automatic power adjusting apparatus activates the automatic voltage adjusting apparatus when the phase tap is controlled, the automatic voltage adjusting apparatus activates the automatic power adjusting apparatus when the voltage tap is controlled, and the automatic power adjusting apparatus suppresses the effective power of the transmission line to the value smaller than the predetermined value while the automatic voltage adjusting apparatus is performing an automatic control, to maintain the system voltage within the predetermined range.

2. The substation automatic control system according to claim 1, wherein the instrument transformer includes first and second instrument transformers configured to transmit electrical parameters to the automatic power adjusting apparatus and the automatic voltage adjusting apparatus, respectively, that are provided at one of a primary winding and a secondary winding of the voltage/effective-power adjusting transformer.

3. The substation automatic control system according to claim 1, wherein when the effective power of the transmission line exceeds a predetermined limit value for a time equal to or longer than a predetermined time limit value, the automatic power adjusting apparatus outputs the phase-tap control command to the phase tap of the voltage/effective-power adjusting transformer to suppress the effective power of the transmission line to the value smaller than the predetermined value.

4. The substation automatic control system according to claim 1, wherein when an activation condition is input externally after the effective power of the transmission line has been suppressed, the automatic power adjusting apparatus restores the phase tap to an initial position of the phase tap before suppressing the effective power, while the automatic voltage adjusting apparatus is performing the automatic control, to maintain the system voltage.

5. The substation automatic control system according to claim 1, wherein the automatic voltage adjusting apparatus activates the automatic power adjusting apparatus, without outputting the voltage-tap control command, when the voltage tap takes a position forbidden in the voltage/effective-power adjusting transformer, and the automatic power adjusting apparatus activates the automatic voltage adjusting apparatus, without outputting the phase-tap control command, when the phase tap takes a position forbidden in the voltage/effective-power adjusting transformer.