CN205248805U

CN205248805U - Novel DVR voltage compensation device

Info

Publication number: CN205248805U
Application number: CN201520804890.1U
Authority: CN
Inventors: 王宝安; 朱淼; 詹国敏; 万杰星
Original assignee: YANGZHOU HUIJIENENG ELECTRIC POWER & ELECTRONIC EQUIPMENT Co Ltd
Current assignee: YANGZHOU HUIJIENENG ELECTRIC POWER & ELECTRONIC EQUIPMENT Co Ltd
Priority date: 2015-10-15
Filing date: 2015-10-15
Publication date: 2016-05-18
Anticipated expiration: 2025-10-15

Abstract

The utility model discloses a DVR voltage compensation device, it mainly comprises super capacitor energy storage component, DC -DC converter, three -phase bridge dc -to -ac converter and adjunct circuit and thyristor. UPQC topological graph for traditional has removed the series connection part, series transformer and series connection dc -to -ac converter promptly, and the bidirectional thyristor of having established ties between system power supply AC and load M, connected in parallel DC -DC circuit and energy storage device of shunt chopper direct current side simultaneously. The utility model provides a voltage dip problem of distribution network, improved the power factor of load, reduced electric wire netting harmonic current, reduced not a series of influences of bringing of balance problem of electric wire netting.

Description

A kind of novel DVR voltage compensating device

Technical field

The utility model relates to a kind of for low-voltage distributing line reactive-load compensation, voltage dip compensate, the uneven novel DVR voltage compensating device of administering of harmonic compensation.

Background technology

Along with scientific and technical development and the expansion of industry size, the power consumption of each department of economy is in continuous increase, increasing user adopts that performance is good, efficiency is high but high technology equipment to power supply characteristic sensitive, as: robot, automatic production line, precise numerical control machine, high precision measuring instrument and computer information management system etc. These systems and equipment are very responsive to the various interference of electrical network, and any power quality problem all may cause great economic loss, brings bad social influence. In custom power quality problem is complained, more than 90% relate to Problem of Voltage Temporary-Drop; Statistics and case reflection show, cause most factors of consumer misoperation or power failure also to be caused by voltage dip.

Voltage dip refers to the event that supply voltage declines suddenly at short notice. International Electrotechnical Commission (IEC) is defined as rms voltage by voltage dip and drops to 90%～1% of rated value, institute of Electrical and Electronic Engineers (IEEE) is defined as and drops to 90%～10% of rated value, and its typical case's duration is 0.5～30 cycle. Serious voltage dip quits work initiation consumer, or causes produced product quality to decline, its severity degree because of the characteristic of consumer different.

The improvement of voltage dip is a complex engineering, conventionally makes main equipment load can bear the voltage dip of frequent generation by auxiliary equipment is set. The voltage dip controlling device of studying both at home and abroad at present mainly contains dynamic electric voltage recovery device (DVR) and the uninterrupted power source (UPS) etc. of AC system. To containing the device of dc bus, if install UPS compensation equipment additional, because of characteristics such as UPS service life are short, discharge current is little and the charging interval is long, the cost performance of system is lower; If install the devices such as AC system DVR additional, because system main circuit exists 2 inverter circuits, not only reduce system works efficiency, but also increased cost.

Summary of the invention

The utility model provides a kind of novel DVR voltage compensating device, its objective is using high-power thyristor and the PWM collating unit based on ultracapacitor energy storage as one, solve the problem of three-phase voltage sag, improve the power factor of load, the harmonic current of reduction system, improve power supply quality, ensure the precision equipment of quality of power supply sensitivity is normally moved.

The utility model adopts following scheme to realize:

Novel UPQC device comprises single-phase BOOST mu balanced circuit (A), voltage type PWM rectifier (B), the soft start loop (7) being made up of main contactor, charging resistor and auxiliary contactor and three-phase anti-parallel thyristor (8), three-phase anti-parallel thyristor (8) is connected in transmission line of electricity, single-phase BOOST mu balanced circuit (A), voltage type PWM rectifier (B) and soft start loop (7) are connected in series, and are finally connected in parallel on the output port of three-phase anti-parallel thyristor (8).

Single-phase BOOST mu balanced circuit (A), it is characterized in that comprising bank of super capacitors (1), boost reactor (2), boost inverter (3), bank of super capacitors (1) is connected in series with boost reactor (2), the mid point of access boost inverter (3), the positive pole of single-phase BOOST mu balanced circuit and negative pole are linked into the both positive and negative polarity of die mould PWM rectifier (B).

Voltage type PWM rectifier (B), it is characterized in that comprising direct current support capacitor group (4), PWM inverter (5), three-phase grid reactor (6), RC filtering (9), the both positive and negative polarity of direct current support capacitor group (4) connects the both positive and negative polarity of PWM three-phase IGBT full-bridge, the mid point of each half-bridge is connected with grid-connected reactor, finally accesses respectively the three-phase of soft start loop (7).

Useful technique effect of the present utility model is: novel DVR voltage compensating device is in the time that system voltage is normally worked, and device operates in active power filtering pattern, has compensated the harmonic current in circuit, out-of-balance current and reactive current. Greatly improve the power supply quality of system. In the time of system generation voltage dip, novel DVR voltage compensating device discharges by bank of super capacitors, supports the normal operation of sensitive loads, has greatly improved continuity and the reliability of load power supply. Therefore, novel DVR voltage compensating device is round-the-clock has ensured that equipment normally moves continuously.

Brief description of the drawings

Fig. 1 is the novel DVR voltage compensating device of the utility model structural representation;

In figure: bank of super capacitors (1), boost reactor (2), boost inverter (3), direct current support capacitor group (4), PWM inverter (5), three-phase grid reactor (6), soft start loop (7), three-phase anti-parallel thyristor (8), RC filtering (9).

Detailed description of the invention

Below in conjunction with Figure of description and embodiment, the utility model is done to progressive explanation.

(1) in the time of system normal power supply, control bidirectional thyristor conducting, novel DVR voltage compensating device operates in active power filtering pattern. Dc bus is operated within the scope of normal voltage, when ultracapacitor array voltage is during lower than rated operational voltage, ultracapacitor is charged. Ultracapacitor discharge control system adopts the double circle structure of outer voltage, current inner loop, the restriction of the stagnant chain rate by actual charge current and reference charge electric current and to maximum switching frequency, generation signal controlling IGBT switch g7 and g8 constant-current charge. Constant-current charge is conducive to the protection to energy storage device, and dynamic response is very fast. Harmonic current in detection load simultaneously, reactive current and out-of-balance current, become these component combination the export target value of DVR device, output current and desired value comparison that will output PWM inverter, produce signal controlling IGBT switch g1～g6, export target electric current. Finally reach the object to super capacitor charging and compensation harmonic reactive current. By the time, after having charged, BOOST voltage stabilizing charging circuit is in floating charge state.

(2), in the time that voltage dip fault appears in system, first control bidirectional thyristor and turn-off. BOOST voltage stabilizing charging circuit is transferred to discharge condition at once, and super capacitor electric discharge, charges to voltage type PWM rectifier (B) direct current capacitors group. Ultracapacitor discharge control system adopts the double circle structure of outer voltage, current inner loop, ensures that direct current capacitors group voltage stabilization is in suitable scope. Voltage type PWM rectifier is operated in voltage source mode simultaneously, the directly rated voltage of output loading work, and guarantee equipment is normal operation continuously.

Claims

1. a novel DVR voltage compensating device, it is characterized in that, this novel UPQC device comprises single-phase BOOST mu balanced circuit (A), voltage type PWM rectifier (B), the soft start loop (7) being made up of main contactor, charging resistor and auxiliary contactor and three-phase anti-parallel thyristor (8), three-phase anti-parallel thyristor (8) is connected in transmission line of electricity, single-phase BOOST mu balanced circuit (A), voltage type PWM rectifier (B) and soft start loop (7) are connected in series, and are finally connected in parallel on the output port of three-phase anti-parallel thyristor (8).

2. the novel DVR voltage compensating device of one according to claim 1, it is characterized in that, described single-phase BOOST mu balanced circuit (A) comprises bank of super capacitors (1), boost reactor (2), boost inverter (3), bank of super capacitors (1) is connected in series with boost reactor (2), the mid point of access boost inverter (3), the positive pole of single-phase BOOST mu balanced circuit and negative pole are linked into the both positive and negative polarity of die mould PWM rectifier (B).

3. the novel DVR voltage compensating device of one according to claim 1, it is characterized in that, described voltage type PWM rectifier (B) comprises direct current support capacitor group (4), PWM inverter (5), three-phase grid reactor (6), RC filtering (9), the both positive and negative polarity of direct current support capacitor group (4) connects the both positive and negative polarity of PWM three-phase IGBT full-bridge, the mid point of each half-bridge is connected with grid-connected reactor, finally accesses respectively the three-phase of soft start loop (7).