CN-121984337-A - Single-tube fault tolerance operation method, storage medium and equipment for high-capacity sea wind converter

CN121984337ACN 121984337 ACN121984337 ACN 121984337ACN-121984337-A

Abstract

The invention discloses a single-tube fault tolerance operation method, a storage medium and equipment of a large-capacity sea wind converter, A split inductance type composite clamping bridge arm is formed by reconstructing a healthy half bridge arm and a half bridge arm at the complementary position of the healthy half bridge arm in the fault bridge arm, so that single-tube fault tolerance operation is realized. According to the optimized fault-tolerant operation mode, the power loss of the switching tube in the converter is shared by a plurality of radiators in a fault phase, so that the operation temperature of the switching tube is reduced, the single-tube fault-tolerant operation power limit of the converter can be improved on the basis of keeping the temperature balance of the radiators, and the power generation loss is further reduced.

Inventors

XIAO HUAFENG
WANG XIAOBIAO
CHEN TAO
TANG CUNWEN
SUN ZUYONG
SHI LEI

Assignees

东南大学
国电南瑞科技股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260123

Claims (8)

1. A single-tube fault tolerance operation method of a high-capacity sea wind converter is applied to a sea wind power converter system and is characterized in that a half bridge arm where a fault is located is cut off, the rest healthy half bridge arm in the fault bridge arm and the half healthy bridge arm in a fault phase are constructed into a complete inversion bridge arm to form a split inductance type composite clamping bridge arm, fault tolerance operation of the single-tube fault is achieved, split inductance in the split inductance type composite clamping bridge arm is composed of an original fault phase bridge arm output filter inductance and a non-fault phase output filter inductance, and a complete inversion bridge arm formed by compounding the healthy half bridge arm and the non-fault phase bridge arm have the same clamping function structure.
2. The single-tube fault tolerant operation method of the high-capacity sea wind converter of claim 1, wherein in an offshore wind power converter system, driving signals of a switching unit where a fault switching tube is located are closed, switching tubes which are located at the same position as a fault phase healthy switching tube in an in-phase non-fault bridge arm are not enabled, heat dissipation power of the switching tube absorbed by a radiator of the in-phase non-fault bridge arm is transferred to the radiator of the fault bridge arm, the fault phase bridge arm is reconstructed by adopting a split inductance structure, and the temperature of the switching tube of the fault phase is increased to the temperature of the switching tube when the converter outputs rated power.
3. The single-tube fault-tolerant operation method of the high-capacity sea wind converter of claim 1, wherein the number of parallel converters in the offshore wind converter system is more than or equal to 2.
4. A single tube fault tolerant method of operation for a high capacity marine wind power converter as defined in claim 1, wherein the converter circuit configuration in the marine wind power converter system is one or more of a three phase H-bridge converter, a three phase diode neutral point clamped converter and a three phase active neutral point clamped converter.
5. The single-tube fault tolerance operation method of the high-capacity sea wind converter of claim 1, wherein the power switching device in the sea wind converter system is IGBT or MOSFET or IGCT or IEGT, and can share a direct current bus or not.
6. A single-tube fault-tolerant operation method of a large capacity sea wind converter as set forth in claim 1, wherein the current value of the switching tube is increased when the single-tube fault-tolerant operation occurs The times are specifically as follows: ; Wherein i' ref is the network access current given by single-tube fault-tolerant operation, and i ref is the network access current given by rated power output.
7. A non-transitory machine-readable storage medium having stored thereon executable code which when executed by a processor of an electronic device causes the processor to perform a high capacity sea-wind converter single tube fault tolerant method of operation as claimed in any one of claims 1 to 6.
8. A computer apparatus, comprising: A memory having executable code stored thereon; A processor for executing the executable code to cause the computer device to perform the operations of a single tube fault tolerant method of operation of a high capacity sea wind current transformer as claimed in any one of claims 1-6.

Description

Single-tube fault tolerance operation method, storage medium and equipment for high-capacity sea wind converter Technical Field The invention belongs to the technical field of wind power generation, and mainly relates to a single-tube fault tolerance operation method, a storage medium and equipment of a high-capacity sea wind converter. Background The wind power generation has fast speed increasing in renewable energy power generation, and the offshore wind energy resources are rich, the occupied area is small, and the installed scale of the offshore wind power is continuously and rapidly expanded. The offshore wind turbine has large power capacity, and a plurality of converter units are commonly used for the offshore wind power converter in parallel to improve the generated energy and the reliability. The offshore wind power fluctuation is large, the working environment of the wind power converter is complex, and the faults of the offshore wind power converter are difficult to completely avoid. As the offshore wind farm is far away from the coast, the power level of the wind turbine is high, and the offshore wind turbine can cause larger power generation loss once the offshore wind turbine is stopped due to failure. According to the statistics of failure rates of internal components of converters in various industrial applications, power semiconductor devices are the devices most prone to failure, and the failure rates of driving circuits and capacitors connected with the power semiconductor devices are high. Therefore, the fault-tolerant operation of the offshore wind power converter system after the power semiconductor device is in fault has great significance for improving the power generation capacity of the offshore wind power system. The fault can be conveniently identified and positioned to a specific fault switching tube through the characteristic analysis or state detection of the electric quantity output by the converter. After the fault, the converter system performs fault-tolerant operation by controlling the rest healthy switching tubes so as to reduce the power generation loss of the system. And because the number of elements is small when a single pipe fails, the occurrence probability is higher, and the influence on the generating capacity of the offshore wind power converter system is larger. For this reason, researchers Long Bo at the university of electronics and technology in "Fault-Tolerant Sequential MPC for Vertical Switch Open-Circuit Fault and ZSCC Suppression for Parallel T-Type Converters" published in journal IEEE Transactions on Power Electronics analyze fault-tolerant operation control methods under single-tube open-circuit faults, but the system after the fault still operates according to rated power output, and may exceed the power class of the power device, resulting in damage to the device and expansion of the fault. The university of Shanghai traffic Cai Xu teaches that team in "Reconfigurable control for fault-tolerant of parallel converters in PMSG wind energy conversion system" published in journal IEEE Transactions on Sustainable Energy in 2019, the entire inverter leg where the fault switching tube is located is cut off, and the other legs of the fault phase remain in operation, maintaining fault tolerant operation of the converter system. After the fault, the maximum output power of the converter system in fault-tolerant operation is limited to half of the rated power. However, the output power limit of the system after the fault is lower, and the power generation amount loss of the offshore wind turbine is large. Because the fault bridge arm is cut off, only one bridge arm transmits power in the fault phase when the converter system operates in a fault-tolerant mode. Therefore, the operating state of the healthy switching tube in the fault phase is identical to the operating state of the converter when rated power is output compared to the normal operation of the converter system. Because the heat dissipation environment is unchanged, the loss and junction temperature of the healthy switching tube are kept unchanged, the junction temperature of the switching tube and the temperature of the radiator are higher, the running state of the switching tube cannot be improved, and the switching tube is not matched with the output power grade of the converter. For a fault bridge arm in a fault phase, as the fault bridge arm is completely cut off, a switching tube in the whole bridge arm stops running, so that the heat power born by a radiator of the fault bridge arm is basically 0, the temperature of the radiator is low, and the operation of the converter is adversely affected in an offshore salt mist humid environment. In summary, under the existing single-tube fault tolerance operation mode, the switching tube and the radiator of the healthy bridge arm in the system still keep high-temperature operation, the radiator of the fault bridge arm is in an idle state, the radiat