CN104659793A - Novel series compensation device for power distribution network - Google Patents

Abstract

The invention discloses a novel series compensation device for a power distribution network. According to the novel series compensation device, existing series compensation devices for power distribution networks are improved, power electronic elements replace original switching elements, an overhaul loop and a bypass loop are combined into a bypass loop which is connected with a damping loop in parallel, and related voltage-limiting resistance loops are cancelled. With the adoption of the series compensation device, the response speed of the device is increased, the structure of the device is optimized, and the cost is saved.

Description

A kind of new distribution net series compensation device

Technical field

The invention belongs to electric power system power system reactive power compensation category, be applicable to low-voltage series compensating device.

Background technology

In electric power system, a large amount of load is transferred to user by power distribution network, and therefore the quality of voltage direct relation of power distribution network the electricity consumption satisfaction of user.Series compensation device effectively can improve the quality of voltage of distribution network line, reduce the effect of Voltage Drop, and has the feature of load " self adaptation " voltage-regulation and real-time response.Be particularly useful for remote mountain village electricity consumption, and some end is with the circuit of high capacity motor load (as sawmill, mine, disintegrating machine, newborn machine processed).Again because intrinsic load " self adaptation " the voltage-regulation feature of distribution series capacitor, distribution string is mended generally not to be needed to adopt controllable type but fixed capacitor, and distribution fixed series capacitors is compared controllable serial capacitor and had more economy.

And present low-voltage network and grid series compensation device similar, not according to the structure that the different choice of voltage is suitable, cause the shortcoming that equipment cost is high, response speed is slow.

The present invention is according to the feature of power distribution network low-voltage, the structure of series compensation device is simplified, adopts power electronic device to substitute the switching device of original equipment, accelerate the responsiveness of equipment, decrease the cost of equipment, be more conducive to series compensation device equipment and apply at power distribution network.

Summary of the invention

The object of the invention is to the structure simplifying series compensation device, utilize the feature of the quick response of power electronic equipment to accelerate the reaction speed to fault of equipment, reduce the manufacturing cost of equipment simultaneously, advantageously apply in power distribution network in series compensation equipment.

The present invention is realized by following technical proposal.

A kind of new distribution net series compensation device, feature of the present invention is:

1) power electronic element is adopted to replace original switch element;

2) loop will be overhauled and bypass loop merges;

3) in bypass loop, increase by one group of current limiting reactor.

When the present invention normally runs, DS1, DS2, DS3 are closed, and G1, DS4, DS5 disconnect, and electric current flows through C1, plays voltage compensation effect.During short trouble, the electric current flowing through capacitor C1 increases instantaneously, causes the voltage at capacitor two ends sharply to raise.For capacitor for voltage protection; when short circuit current being detected, DS3 closes; now electric current flows through inductance L 1; thus play the effect of the rising of limiting short-circuit current, consider the capacity of flow restricter L1, therefore; need to send order and make G1 conducting; make capacitor C1 out of service, and closed DS4, the energy on releasing capacitor C1.During maintenance, the ground cutter DS5 string that closes fills device and is in inspecting state, and personnel can safeguard in access to plant region.The key equipment parts that string mends device are studied.

The invention has the beneficial effects as follows, simplify the structure of series compensation device, utilize the feature of the quick response of power electronic equipment to accelerate the reaction speed to fault of equipment, decrease the manufacturing cost of equipment simultaneously, advantageously apply in power distribution network in series compensation equipment.

Accompanying drawing explanation

Fig. 1 is structural representation of the present invention.

Embodiment

See Fig. 1, a kind of new distribution net series compensation device, feature of the present invention is:

1) power electronic element is adopted to replace original switch element;

2) loop will be overhauled and bypass loop merges;

3) in bypass loop, increase by one group of current limiting reactor.

When the present invention normally runs, DS1, DS2, DS3 are closed, and G1, DS4, DS5 disconnect, and electric current flows through C1, plays voltage compensation effect.During short trouble, the electric current flowing through capacitor C1 increases instantaneously, causes the voltage at capacitor two ends sharply to raise.For capacitor for voltage protection; when short circuit current being detected, DS3 closes; now electric current flows through inductance L 1; thus play the effect of the rising of limiting short-circuit current, consider the capacity of flow restricter L1, therefore; need to send order and make G1 conducting; make capacitor C1 out of service, and closed DS4, the energy on releasing capacitor C1.During maintenance, the ground cutter DS5 string that closes fills device and is in inspecting state, and personnel can safeguard in access to plant region.The key equipment parts that string mends device are studied.

Claims (1)

1. a new distribution net series compensation device, is characterized in that:

1) power electronic element is adopted to replace original switch element; 2) loop will be overhauled and bypass loop merges; 3) in bypass loop, increase by one group of current limiting reactor.