Apparatus and method for supplying hybrid power of offshore plant

• US 9,954,357 B2
• Filed: 12/18/2014
• Issued: 04/24/2018
• Est. Priority Date: 12/18/2013
• Status: Expired due to Fees

• Current Assignee: Daewoo Shipbuilding & Marine Engineering Company Limited (Government of South Korea)
• Original Assignee: Daewoo Shipbuilding & Marine Engineering Company Limited (Government of South Korea)
• Inventors: Jung, Ho Young, Bae, Young Ho
• Primary Examiner(s): Deberadinis, Robert
• Application Number:
  US15/106,246
• Publication Number:
  US 20160322815A1
• Time in Patent Office: 1,223 Days
• CPC Class Codes: E21B 3/022 Top drives
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 1/106 for load balancing, symmetrisation, or sharing
• CPC Class Codes: H02J 2300/10 The dispersed energy generation being of fossil origin, e.g. diesel generators
• CPC Class Codes: H02J 2310/12 The local stationary network supplying a household or a building
• CPC Class Codes: H02J 3/28 Arrangements for balancing of the load in a network by storage of energy
• CPC Class Codes: H02J 3/30 using dynamo-electric machines coupled to flywheels
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/36 Arrangements for transfer of electric power between ac networks via a high-tension dc link
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02M 3/04 by static converters
• CPC Class Codes: H02P 3/18 for stopping or slowing an ac motor
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids
• CPC Class Codes: Y02E 60/60 Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Abstract

A power supply system offshore plant comprises: a generator; an AC/DC converter converting, AC generated from the generator into DC to supply the direct current to a DC bus; a power load connected to the DC bus to generate regenerative power; a first power storage unit for storing power when a voltage of the DC bus is maintained at a level of a first threshold value or higher for a first time period, and supplying the stored power to the DC bus when the voltage of the DC bus is maintained at a level of a second threshold value or lower for a second time period; and a first resistance unit for consuming power when the voltage of the DC bus is maintained at the level of the first threshold value or higher for a third time period. The third time period is longer than the first time period.

Claims

1. A hybrid power supply apparatus for an offshore plant, comprising:

a power generator;

an AC/DC converter converting alternating current produced by the power generator into direct current and supplying the direct current to a DC bus;

an electric power load connected to the DC bus and generating regenerative power;

a first power storage unit storing electric power when a voltage of the DC bus is maintained at a first threshold value or higher for a first period of time and supplying electric power to the DC bus when the voltage of the DC bus is maintained at a second threshold value or less for a second period of time; and

a first resistor consuming electric power when the voltage of the DC bus is maintained at the first threshold value or higher for a third period of time,

wherein the third period of time is longer than the first period of time.

2. The hybrid power supply apparatus according to claim 1, further comprising:

a first DC/DC converter connected to the DC bus,

wherein the first power storage unit and the first resistor are connected to the first DC/DC converter.

3. The hybrid power supply apparatus according to claim 1, further comprising:

a first DC/DC converter connected to the DC bus; and

a second DC/DC converter connected to the DC bus,

wherein the first power storage unit is connected to the first DC/DC converter, and the first resistor is connected to the second DC/DC converter.

4. The hybrid power supply apparatus according to claim 1, wherein the first power storage unit is an ultracapacitor.

5. The hybrid power supply apparatus according to claim 1, wherein the electric power load is a draw-works.

6. The hybrid power supply apparatus according to claim 1, wherein the electric power load is a top drive.

7. A hybrid power supply method for an offshore plant, comprising:

measuring voltage of a DC bus;

storing, by a power storage unit, electric power when a voltage of the DC bus is maintained at a first threshold value or higher for a first period of time;

supplying, by the power storage unit, electric power to the DC bus when the voltage of the DC bus is maintained at a second threshold value or less for a second period of time,

wherein the DC bus is connected to an electric power load generating regenerative power.

8. The hybrid power supply method according to claim 7, further comprising:

consuming, by a resistor, electric power when the voltage of the DC bus is maintained at the first threshold value or higher for a third period of time,

wherein the third period of time is longer than the first period of time.

9. The hybrid power supply method according to claim 8, wherein the DC bus is connected to a first DC/DC converter, and the power storage unit and the resistor are connected to the first DC/DC converter.

10. The hybrid power supply method according to claim 8, wherein the DC bus is connected to a first DC/DC converter and a second DC/DC converter, and the power storage unit is connected to the first DC/DC converter and the resistor is connected to the second DC/DC converter.

11. The hybrid power supply method according to claim 7, wherein the power storage unit is an ultracapacitor.

12. The hybrid power supply method according to claim 7, wherein the electric power load is a draw-works.

13. The hybrid power supply method according to claim 7, wherein the electric power load is a top drive.