SUBSTATION AUTOMATIC CONTROL SYSTEM

• US 20120274303A1
• Filed: 07/09/2012
• Published: 11/01/2012
• Est. Priority Date: 01/25/2010
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yamamori, Wataru, Saotome, Hirotoshi, Tomaru, Koichi
• Granted Patent: US 8,494,684 B2
• Time in Patent Office: Days
• US Class Current: 323/305
• 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 is equipped with a voltage tap and a phase tap;

an automatic power adjusting apparatus configured to obtain electrical parameters on the transmission line via an instrument transformer, to calculate effective power on the transmission line and to output a phase-tap control command to the phase tap of the voltage/effective-power adjusting transformer, thereby to suppress the effective power to a value smaller than a prescribed value if the effective power has exceeded the prescribed value; and

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

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

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

4. The substation automatic control system according to claim 1, wherein if an activation condition is input externally after the effective power on the transmission line has been suppressed, the automatic power adjusting apparatus restores the phase tap to the initial position of the phase tap before suppressing the effective power, while the automatic voltage adjusting apparatus is performing an automatic control, thereby maintaining transmission-side 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 a voltage-tap control command, if the voltage tap takes a position forbidden in the voltage/effective-power adjusting transformer, and automatic power adjusting apparatus activates the automatic voltage adjusting apparatus, without outputting a phase-tap control command, if the phase tap takes a position forbidden in the voltage/effective-power adjusting transformer.