CN204178883U

CN204178883U - HV Auxiliary Transformer excitation winding structure

Info

Publication number: CN204178883U
Application number: CN201420688304.7U
Authority: CN
Inventors: 徐春丽; 杨正莉; 李�和
Original assignee: North China Electric Power Design Institute of China Power Engineering Consulting Group Corp
Current assignee: North China Power Engineering Co Ltd of China Power Engineering Consulting Group
Priority date: 2014-11-17
Filing date: 2014-11-17
Publication date: 2015-02-25
Anticipated expiration: 2024-11-17

Abstract

The utility model relates to a kind of HV Auxiliary Transformer excitation winding structure, it comprises the excitation system be connected with generator, HV Auxiliary Transformer is connected with generator, and this HV Auxiliary Transformer arranges the special winding of excitation, directly connects excitation system by the special winding of this excitation.The rated capacity of the special winding of this excitation is at 3 ~ 12MVA.The utility model adopts said structure, because HV Auxiliary Transformer is arranged in outside factory building, arrangement condition is almost without any restriction, and radiating condition but improves a lot, meanwhile owing to eliminating special excitation transformer in factory building, the apparatus arrangement in factory building and heat radiation are all made moderate progress.

Description

HV Auxiliary Transformer excitation winding structure

Technical field

The utility model is applied to turbo generator and hydraulic generator self-shunt excitation system, particularly a kind of static exciter winding construction.

Background technology

At present, what turbo generator and hydraulic generator self-shunt excitation system generally adopted is special excitation transformer, and excitation transformer is usually placed in main power house.As shown in Figure 1, for existing routine adopts the system construction drawing of special excitation transformer.Generator 1 is connected to main transformer, and connects HV Auxiliary Transformer 2, and generator is provided with excitation system 3, and excitation system is connected with excitation transformer 31.Because caloric value when excitation transformer works is comparatively large, therefore failure rate is obviously more higher than other transformer.According to our incomplete statistics, since applying China from shunt excitation technology, successively occurred three river power plant excitation transformer faults on January 13rd, 2000, on February 24th, 2011 certain power plant's excitation transformer fault, on July 12nd, 2012 Henan with power power plant excitation transformer fault, on March 28th, 2012 Chaozhou power plant excitation transformer fault, and the too high phenomenon of excitation transformer temperature is very general especially.The highest has the situation reaching 135 DEG C, constitutes a threat to the long-term safety of equipment.

The feature of this excitation mode is:

1. excitation transformer is dedicated transformer, is connected on generator outlet, and does not have off device.

2. excitation transformer almost adopts epoxy resin pouring transformer bar none, and the transformer heat-sinking capability of this structure is poor, and therefore failure rate is higher.

3., because supplier is by the restriction of cost, be usually difficult to the solution in order to improve heat dispersal situations, excitation transformer being taked to essence.

Excitation transformer, to the apparatus arrangement in factory building and heat radiation all make moderate progress.

Utility model content

In view of this, the technical problem that the utility model solves is, utilize the feature of HV Auxiliary Transformer, solve the excitation transformer problem that operationally temperature is too high, reduce the fault of excitation transformer, effectively utilize Capacity Margin (mainly the nargin of iron core) that HV Auxiliary Transformer is in operation and good radiating condition (there is special radiator usually and cooling fan comprises stand-by equipment), solve special excitation transformer and to generate heat serious problem.

The utility model patent adopts following technical scheme: a kind of HV Auxiliary Transformer excitation winding structure, it comprises the excitation system be connected with generator, HV Auxiliary Transformer is connected with generator, this HV Auxiliary Transformer arranges the special winding of excitation, directly connects excitation system by this special excitation winding.

The utility model technology adopts the advantage of technique scheme to be: make full use of the feature that HV Auxiliary Transformer Capacity Margin is large, for excitation winding provides the environment that a radiating condition is good.Meanwhile, because general high voltage station transformer and excitation transformer are all fixedly be connected on generator outlet, all do not cut-off equipment, therefore, reliability is substantially identical.But because HV Auxiliary Transformer is oil-filled transformer, therefore, its radiating condition is better than special excitation transformer (excitation transformer is generally the dry-type transformer of poured with epoxy resin), adds that HV Auxiliary Transformer is arranged in outdoor, more very favourable to heat radiation.Like this, the reliability of excitation system can be improved widely, therefore can run for the long-term stability of unit, shorten the time between overhauls(TBO) and create conditions, also can increase energy output, for power plant creates more benefit simultaneously.

Accompanying drawing explanation

Fig. 1 is the system diagram that existing routine adopts special excitation transformer.

Fig. 2 is structural representation of the present utility model.

Embodiment

As shown in Figure 2, the utility model HV Auxiliary Transformer excitation winding structure, it comprises the excitation system 3 be connected with generator 1, HV Auxiliary Transformer 2 is connected with generator 1, focus on, this HV Auxiliary Transformer 2 arranges the special winding 21 of excitation, directly connects excitation system 3 by the special winding 21 of this excitation.

According to the parameter of generator excited system in HV Auxiliary Transformer, increase the special winding of excitation that an excitation is special, for excitation system as field power supply.

For China in recent years Generator pool-size constantly increase, make full use of HV Auxiliary Transformer employing oil immersed type and be arranged in outdoor and there is the good condition of heat radiation, the technical scheme that HV Auxiliary Transformer increases excitation winding is proposed, to reach reduction operating temperature, improve operational reliability, for country and enterprise create better, more service conditions.

Although the selection of HV Auxiliary Transformer rated capacity may connect peak load on the transformer under considering various operating mode, but the load of HV Auxiliary Transformer is generally only the 60% ~ 75% even less of rated capacity when normal operation, if (general rated capacity is at 3 ~ 12MVA to increase a special winding of excitation, random groups brand, different and the difference to some extent of capacity), even may not need the capacity increasing transformer core in theory, as long as add around an excitation winding, and the voltage of excitation winding generally only has 0.75kV ~ 1.2kV, withstand voltagely also do not need extra process, therefore the expense increased and special excitation transformer about the same, but heat radiation improves a lot, and be arranged in outside factory building due to HV Auxiliary Transformer, arrangement condition is almost without any restriction, radiating condition but improves a lot, meanwhile owing to eliminating special excitation transformer in factory building, apparatus arrangement in factory building and heat radiation are all made moderate progress.

Claims

1. a HV Auxiliary Transformer excitation winding structure, it comprises the excitation system be connected with generator, and HV Auxiliary Transformer is connected with generator, it is characterized in that, this HV Auxiliary Transformer arranges the special winding of excitation, directly connects excitation system by the special winding of this excitation.

2. HV Auxiliary Transformer excitation winding structure as claimed in claim 1, it is characterized in that, the rated capacity of the special winding of this excitation is at 3 ~ 12MVA.