CN2248913Y - Power transformer for automatically rearranging voltage or phase with improved structure - Google Patents

Abstract

The utility model relates to a power transformer with automatic voltage and phase regulation and an improved structure, which comprises an iron core, a primary coil, a power transformer and a dynamic reactive power compensation power supply device which can adopt silicon controlled rectifier GTO with high power to realize automatic voltage regulation and phase regulation. The power transformer is formed by a voltage regulating coil and a secondary coil. The voltage regulating coil comprises three independent three-phase coils which are in magnetic contacts with the primary coil and the secondary coil and are without electrical contacts. The three coils adopt star connection; one end of the three coils is respectively connected with SVG and the neutral points of the other end are directly connected with ground. The utility model can make work more safe, more reliable and more economic.

Description

Improve the automatic Regulation phase modulation power transformer of structure

The utility model relates to a kind of power transformer, relates to a kind of power transformer of automatic Regulation phase modulation or rather.

The applicant's Chinese invention patent application 95100411.5 " adopts high-power silicon controlled rectifier to realize the power transformer of automatic Regulation phase modulation ", mainly comprises iron core, elementary voltage regulation coil, secondary coil and dynamic passive compensation supply unit SVG.Wherein SVG adopts high-power turn-off SCR GTO to realize the automatic Regulation phase modulation, it is to raise or reduction by the voltage that changes on the dc filter capacitor that phase angle between system voltage and the SVG inverter output voltage forces SVG that SVG regulates reactive power, thereby cause inverter output voltage to increase or minimizing, when the phase angle greater than zero and inverter output voltage during greater than system voltage, SVG injects lagging reactive power to system, i.e. Q＞0.Otherwise when the phase angle less than zero and inverter output voltage during less than system voltage, SVG imports capacitive reactive power to system, i.e. Q＜0.

Allow a tap (being the centre tap of primary winding) and elementary voltage regulation coil one end of elementary voltage regulation coil connect SVG respectively in the above-mentioned patent application technology, the dynamic passive compensation supply unit SVG that utilization is used in big electrical network can move, produce arbitrarily the operating characteristic of perception or capacitive reactive power under positive and negative pilot angle state, by unique tap input power transformer of elementary voltage regulation coil, bear the function of reactor and capacitor by transformer respectively by SVG.If ignore the very little active loss of SVG itself, then its output voltage uO and main flux are at voltage regulation coil internal induction voltage U B homophase.When U0＞UB, the SVG output current is a capacitive, magnetic assist, boosts; When UO＜UB, the SVG output current is a perception, and demagnetize, step-down realize the automatic Regulation (purpose of phase modulation is also for pressure regulation) of power transformer.

The power transformer of said structure, because a tap (tap) of elementary voltage regulation coil meets SVG, promptly adopt the self-coupling mode, be effective under special operational mode, though but belong to effectively earthed system for the network system of 6-35KV, isolated neutral and more than the 110KV but still do not allow for the short circuit current part neutral point of restriction single-phase earthing system for the network system of ground connection, the insulation level of the switch of SVG and adapted thereof, plug-in strip, lightning arrester etc. requires very high, has dangerous, unreliable and uneconomic problem.

The purpose of this utility model is a kind of automatic Regulation phase modulation power transformer that improves structure of design, 95100411.5 patent application technology are made improvements design, the operation principle and the performance that had both kept former technology, can select for use again rated voltage lower, be subjected in overvoltage influence little SVG power electronic equipment and with the switch of SVG adapted, plug-in strip, lightning arrester etc., improve fail safe, economy and reliability.

The utility model improves the automatic Regulation phase modulation power transformer of structure, comprises the power transformer and the dynamic passive compensation supply unit that are made of iron core, primary winding, voltage regulation coil and secondary coil, it is characterized in that:

Described voltage regulation coil is three first, second, third coils that independently are wound on the described iron core, one end of first, second, third coil connects described dynamic passive compensation supply unit, the other end of first, second, third coil and ground connection respectively.

The coil turn of described voltage regulation coil is 5% to 30% of a described primary winding coil turn.

Because three voltage regulation coils are independently, with once, secondary coil has only getting in touch of magnetic, there is not the contact of electricity, and the voltage regulation coil of three-phase is connected into star, its neutral-point solid ground, thereby can make voltage regulation coil, reduce, be subjected to the rated voltage of the switch of SVG adapted, plug-in strip, lightning arrester, SVG power electronic equipment in overvoltage influence for a short time, realize safety, economic, purpose reliably.

Further specify technology of the present utility model below in conjunction with the embodiment accompanying drawing

Fig. 1. improve the automatic Regulation phase modulation power transformer electrical schematic diagram of structure

Fig. 2. improve the automatic Regulation phase modulation power transformer structural representation of structure

Referring to Fig. 1, the automatic Regulation phase modulation power transformer that improves structure mainly comprises iron core 10, primary winding 11, secondary coil 12, voltage regulation coil 13 and dynamic passive compensation supply unit 14.Voltage regulation coil 13 is independent, and three phase voltage regulating coil L1, L2, L3 are connected into star, its neutral-point solid ground.And the acquisition of 14 protections of dynamic passive compensation supply unit, signal power source then can be adopted multiple mode, for example can decide on the on-site customer concrete condition from the secondary coil side by acquisitions such as step-down transformer, rectifiers.

Be provided with measuring circuit (sample circuit), protective circuit, microcomputer, drive circuit and turn-off SCR in the dynamic passive compensation supply unit 14.Power transformer of the present utility model has utilized the characteristic of dynamic passive compensation supply unit, under positive and negative pilot angle state, move, produce perception or capacitive reactive power arbitrarily, input power transformer voltage regulation coil 13, bear the function of reactor and capacitor group respectively, by detecting the variation of power transformer voltage, if ignore the very little active loss of SVG itself, the voltage U B homophase under the main flux effect, responded to of its output voltage U 0 and voltage regulation coil then.When UO＞UB, the SVG output current is a capacitive, magnetic assist, boosts; As U＜UB, the SVG output current is a perception, demagnetize, step-down, thus the voltage of power transformer is adjusted on stepless difference ground, guarantees the stability of user's voltage.

Referring to Fig. 2, three-phase power transformer is difference coiling primary winding 11a, 11b, 11c on three posts of unshakable in one's determination 10, secondary coil 12a, 12b, 12c and voltage regulation coil L1, L2, L3, L1, L2, L3 one end A, B, C connect dynamic passive compensation supply unit SVG, other end ground connection.The number of turn of voltage regulation coil L1, L2, L3 accounts for 5～30% of primary winding 11a, 11b, the 11c number of turn, is optimum range with 10～20%.

The utility model technology is replenishing and improving 95100411.5 patent application cases, in the implementation process of this invention technology, in order to obtain higher safety, economy, reliability, and change part-structure in the former technical scheme, make technical scheme more perfect, but keep former operation principle and performance constant.By adopting independently the three phase voltage regulating coil and be connected into star and allow neutral-point solid ground, and can reduce insulation level requirement to SVG, switch, plug-in strip, lightning arrester etc., the more reliable electricity safety of working is also more economical.

Claims (2)

1. an automatic Regulation phase modulation power transformer that improves structure comprises the power transformer and the dynamic passive compensation supply unit that are made of iron core, primary winding, voltage regulation coil and secondary coil, it is characterized in that:

Described voltage regulation coil is three first, second, third coils that independently are wound on the described iron core, one end of first, second, third coil connects described dynamic passive compensation supply unit, the other end of first, second, third coil and ground connection respectively.

2. the automatic Regulation phase modulation power transformer of improvement structure according to claim 1 is characterized in that: the coil turn of described voltage regulation coil is 5% to 30% of a described primary winding coil turn.

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