CN113644659A - Voltage stabilizer for distribution transformer - Google Patents

Abstract

The invention relates to the technical field of electric power, in particular to an automatic voltage stabilizing device of a power transformer, and more particularly relates to a voltage stabilizing device of a distribution transformer. The invention has the advantages of simple control, safety, reliability, high voltage regulation speed, wide input voltage, high voltage stabilization precision and long continuous safe operation time.

Description

Voltage stabilizer for distribution transformer

Technical Field

The invention relates to the field of electric power technology, in particular to a voltage stabilizing device of a distribution transformer.

Background

The transformer is an important device for power distribution of a power grid, and the problem of power supply shortage needs to be solved urgently when various regions in the world are in the peak period of power construction at present. In order to relieve the situation of short power supply, power companies in various regions around the world increase the total length of a power transmission line, increase the investment scale of power grid construction, further expand the transformation capacity, provide a wide development space for the transformer industry, and promote the good development of the transformer manufacturing industry.

Electric power is one of the most important energy sources used in modern industry, agriculture and modern society life, and various industrial electric equipment is widely influenced by voltage change. With the development of science and technology, electricity will play a greater role in the development of the human society.

Voltage quality issues include the following:

voltage deviation: the operation voltage value is within the range of +/-10% of the rated voltage value;

under voltage: the operation voltage value is within the range of 90-80% of the rated voltage value, and the voltage change lasts for more than 1 minute;

③ overvoltage: the operation voltage value is within the range of 110-120% of the rated voltage value, and the voltage change lasts for more than 1 minute;

fourthly, short-time undervoltage, wherein the time range is 3 seconds to 1 minute;

short-time overvoltage, wherein the time range is 3 seconds to 1 minute;

sixthly, temporary overvoltage is carried out, wherein the time range is 60 milliseconds to 3 seconds;

seventhly, temporarily undervoltage, wherein the time range is 60 milliseconds to 3 seconds;

the instantaneous overvoltage is in the time range of 10-60 milliseconds;

ninthly, instantaneous under-voltage, wherein the time range is 10-60 milliseconds;

the three-phase voltage unbalance of the R is that the unevenness of the running three-phase voltage is more than or equal to 2 percent and the short time is more than or equal to 4 percent.

According to the safety voltage requirement of the electric equipment, the voltage difference change of the end voltage of the electric equipment is +/-5%, some requirements are higher, the voltage difference change of the end voltage of the electric equipment is less than or equal to 2.5% and the unbalance degree of the three-phase voltage is less than or equal to 2.6%.

The main voltage regulating transformers on the market at present have 3: the transformer comprises a constant magnetic flux voltage regulating transformer, a variable magnetic flux voltage regulating transformer and an on-load voltage regulating transformer. Firstly, the constant magnetic flux voltage regulating transformer adopts the adjustment of the number of turns of a high-voltage winding to change the transformation ratio relation between the high-voltage winding and a low-voltage winding so as to realize the stability of output voltage. It has the advantages of low price, reliable performance, and no synchronous adjustment along with the voltage change, and can only be adjusted after power failure. Secondly, the variable magnetic flux voltage regulating transformer adopts the adjustment of the number of turns of the low-voltage winding to change the transformation ratio relation between the high-voltage winding and the low-voltage winding so as to realize the stability of output voltage. It has low cost and reliable performance, and can not be synchronously regulated with the change of voltage, and can only be regulated after power failure. And thirdly, the on-load tap changing transformer adopts a multi-tap excitation winding to be connected in series with the high-voltage winding, and the tap of the excitation winding is adjusted to change the transformation ratio of the high-voltage winding and the low-voltage winding so as to actually output the stable voltage. However, the on-load tap changer is difficult to avoid arcing during voltage regulation, and therefore requires frequent maintenance.

Disclosure of Invention

In order to solve the technical problems, the invention provides a series of automatic voltage stabilizing devices of the power transformer, which have simple operation, safety and reliability, high voltage regulating speed of less than or equal to 10 milliseconds, wide input voltage of more than or equal to 125 percent and 75 percent of rated voltage value, high output voltage precision of less than or equal to 2 percent, continuous safe operation time of less than or equal to 1 ten thousand hours, uninterrupted automatic bypass function, real-time automatic monitoring function and the like. The series of automatic voltage stabilizing devices of the power transformers are divided into an automatic voltage stabilizing device for class I power transformers, an automatic voltage stabilizing device for class II combined power transformers, an automatic voltage stabilizing device for class III power transformers and an automatic voltage stabilizing device for class IV combined power transformers, wherein the class I comprises a class I distribution transformer voltage stabilizing device, a class I enveloping coil transformer voltage stabilizing device, a class I split transformer voltage regulating device, a class I iv double-winding transformer voltage stabilizing device, a class I v double-winding transformer automatic voltage regulating device and a class I vi transformer voltage stabilizing device, the class II comprises a class II i distribution transformer voltage regulating device, a class II ii distribution transformer automatic voltage stabilizing device, a class I enveloping coil transformer voltage regulating device, a class II iv double-winding transformer voltage regulating device, a class II transformer voltage regulating device, a class III double-winding transformer voltage regulating device, III ii transformer automatic voltage regulation device, III iii transformer voltage regulation device, IV class includes IVi transformer automatic voltage regulator, IVii double winding transformer automatic voltage regulator, IViii double winding transformer voltage regulation device.

The applicant finds that the first constant flux regulating transformer and the second variable flux regulating transformer can not be synchronously adjusted along with the voltage change, and can only be adjusted after power failure, so that the use of the transformer is troublesome and can not play an effective voltage stabilizing role, and also finds that the excitation current of the transformer is increased when the voltage is increased, so that the magnetic induction intensity B in an iron core is increased, the iron loss is increased, and the temperature rise of the iron core promotes the accelerated insulation aging of a winding. The on-load tap changer is easy to generate electric arc when adjusting voltage, and the phenomenon that short-time undervoltage of power supply can be caused if the on-load tap changer is not frequently overhauled is further found, so that advanced electric equipment stops working or is damaged, even voltage breakdown of a power supply system can be caused, and disorder is caused to production operation and working life of the power utilization area.

The technical scheme I of the invention is a distribution transformer voltage stabilizing device which comprises a distribution transformer and a plurality of groups of voltage reducers and is applied to various voltage grade classifications, various cooling classifications, various shell classifications and various connection classifications and combination classifications except a series of automatic voltage stabilizing devices of power transformers described in the specification of the abstract. The distribution transformer further comprises a distribution transformer high-voltage winding A, a distribution transformer high-voltage winding B, a distribution transformer high-voltage winding C, a distribution transformer high-voltage winding Y, a distribution transformer low-voltage winding a, a distribution transformer low-voltage winding B, a distribution transformer low-voltage winding C, a distribution transformer low-voltage winding Y and a plurality of groups of distribution transformer tuning windings X1, a distribution transformer tuning winding X2, a distribution transformer tuning winding Y1, a distribution transformer tuning winding Y2, a distribution transformer tuning winding Z1 and a distribution transformer tuning winding Z2. The buck also includes a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2, a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2.

In a further improvement, the distribution transformer tuning winding X1 is connected with the distribution transformer tuning winding Y2, the distribution transformer tuning winding X2 is connected to a distribution transformer tuning winding Z1, the distribution transformer tuning winding Z2 is connected to a distribution transformer tuning winding Y1, the distribution transformer tuning winding X1 is further connected with a step-down transformer winding W1, the distribution transformer tuning winding Y1 is further connected with a step-down transformer winding V1, the distribution transformer tuning winding Z1 is also connected with a voltage reducer winding U1, the voltage reducer winding W1 is also connected with a voltage reducer winding V2, the voltage reducer winding V1 is also connected with a voltage reducer winding U2, the voltage reducer winding U1 is also connected with a voltage reducer winding W2, the voltage reducer winding U1 is connected with a voltage reducer winding W2, the buck winding u2 is connected to the buck winding v1 and the buck winding v2 is connected to the buck winding w 1.

The further improvement is that the protective circuit also comprises a bidirectional thyristor WTCU1, a bidirectional thyristor WTCU2, a bidirectional thyristor WTCV1, a bidirectional thyristor WTCV2, a bidirectional thyristor WTCW1, a bidirectional thyristor WTCW2 and a three-phase control protective switch, wherein the bidirectional thyristor WTCU1 is connected between a step-down device winding u1 and a step-down device winding u2, the bidirectional thyristor WTCV1 is connected between a step-down device winding v1 and a step-down device winding v2, the bidirectional thyristor WTCW1 is connected between a step-down device winding w1 and a step-down device winding w2, one end of the bidirectional thyristor WTCU2 is connected to a step-down device winding u1, one end of the bidirectional thyristor CV2 is connected to a step-down device winding v1, one end of the bidirectional thyristor WTCW2 is connected to a step-down device winding w1, the other ends of the bidirectional thyristors WTCU2, WTCU2, WTCU2 are respectively connected to one end of the three-phase protective switch, the other end of the three-phase protective switch is respectively connected to a low-voltage distribution transformer winding a, distribution transformer low-voltage winding b, distribution transformer low-voltage winding c.

The improved touch screen comprises an operating system, a main control system and a driving system, wherein the three-phase input voltage, the three-phase current, the three-phase output voltage, the three-phase current and each group of voltage combined windings are connected to the main control system, the operating system and the driving system are connected to the main control system, the operating system is a touch screen operation interface, and the main control system controls the voltage combined windings to work through the driving system.

By adopting the technical scheme, the invention has the beneficial effects that: the invention provides a voltage stabilizing device of a distribution transformer, which is specifically shown in figure 1. When the power is on or the input voltage is equal to the rated voltage, the master control system controls the bidirectional thyristors WTCU2, WTCV2 and WTCW2 to be turned off, the bidirectional thyristors WTCU1, WTCV1 and WTCW1 are turned on at the same time, the step-down device windings u1 and u2 are short-circuited, the step-down device windings v1 and v2 are short-circuited, the step-down device windings w1 and w2 are short-circuited, the output voltage is equal to the current voltage value, when the input voltage is higher than the rated voltage, the master control system controls the bidirectional thyristors WTCU1, WTCV1 and WTCW1 to be turned off, the bidirectional thyristors WTCU2, WTCV2 and WTCW2 are turned on at the same time, the secondary winding group performs voltage cancellation on the primary winding group, and the output voltage is equal to the rated voltage value. The invention has simple control, safety and reliability, fast voltage regulation speed of less than or equal to 10 milliseconds, wide input voltage of more than or equal to 125 percent of rated voltage value, high output voltage precision of less than or equal to 2 percent, continuous safe operation time of less than or equal to 1 ten thousand hours, large rated capacity of less than or equal to 5000KVA, long service life of less than or equal to 25 years, uninterrupted automatic bypass function, real-time automatic monitoring function and the like, can make up the defects of products on the market, and has the concrete expression that: the constant flux voltage regulating transformer and the variable flux voltage regulating transformer can not be synchronously adjusted along with the voltage change, and can only be adjusted after power failure, so that the transformer is troublesome to use and cannot play an effective voltage stabilizing role, and the excitation current of the transformer is increased when the voltage is increased, so that the magnetic induction intensity B in an iron core is increased, the iron loss is increased, and the temperature rise of the iron core promotes the accelerated insulation aging of a winding. And the on-load tap changer is easy to generate electric arc when adjusting voltage, and short-time undervoltage of power supply can be caused if the on-load tap changer is not frequently overhauled, so that advanced electric equipment stops working or is damaged, even voltage breakdown of a power supply system can be caused, and confusion is caused to production operation and working life of the power utilization area.

Description of the drawings:

fig. 1 is a schematic circuit diagram of a voltage stabilizing device of a distribution transformer in an embodiment of the invention:

Detailed Description

The invention will be described in further detail below with reference to fig. 1 and the specific embodiments:

as shown in fig. 1, a voltage stabilizer for a distribution transformer includes a distribution transformer and a plurality of sets of step-down transformers, and is applied to various voltage class classifications, various cooling classifications, various housing classifications, and various connection classifications and combination classifications except for a series of automatic voltage stabilizers for power transformers described in this abstract specification. The distribution transformer further comprises a distribution transformer high-voltage winding A, a distribution transformer high-voltage winding B, a distribution transformer high-voltage winding C, a distribution transformer high-voltage winding Y, a distribution transformer low-voltage winding a, a distribution transformer low-voltage winding B, a distribution transformer low-voltage winding C, a distribution transformer low-voltage winding Y and a plurality of groups of distribution transformer tuning windings X1, a distribution transformer tuning winding X2, a distribution transformer tuning winding Y1, a distribution transformer tuning winding Y2, a distribution transformer tuning winding Z1 and a distribution transformer tuning winding Z2. The buck also includes a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2, a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2. Further comprising said distribution transformer tuning winding X1 connected to a distribution transformer tuning winding Y2, the distribution transformer tuning winding X2 is connected to a distribution transformer tuning winding Z1, the distribution transformer tuning winding Z2 is connected to a distribution transformer tuning winding Y1, the distribution transformer tuning winding X1 is further connected with a step-down transformer winding W1, the distribution transformer tuning winding Y1 is further connected with a step-down transformer winding V1, the distribution transformer tuning winding Z1 is also connected with a voltage reducer winding U1, the voltage reducer winding W1 is also connected with a voltage reducer winding V2, the voltage reducer winding V1 is also connected with a voltage reducer winding U2, the voltage reducer winding U1 is also connected with a voltage reducer winding W2, the voltage reducer winding U1 is connected with a voltage reducer winding W2, the buck winding u2 is connected to the buck winding v1 and the buck winding v2 is connected to the buck winding w 1. The bidirectional protection circuit also comprises a bidirectional thyristor WTCU1, a bidirectional thyristor WTCU2, a bidirectional thyristor WTCV1, a bidirectional thyristor WTCV2, a bidirectional thyristor WTCW1, a bidirectional thyristor WTCW2 and a three-phase control protection switch, wherein the bidirectional thyristor WTCU1 is connected between a step-down transformer winding u1 and a step-down transformer winding u2, the bidirectional thyristor WTCV1 is connected between a step-down transformer winding v1 and a step-down transformer winding v2, the bidirectional thyristor WTCW1 is connected between a step-down transformer winding w1 and a step-down transformer winding w2, one end of the bidirectional thyristor WTCU2 is connected to the step-down transformer winding u1, one end of the bidirectional thyristor WTCCV 2 is connected to the step-down transformer winding v1, one end of the bidirectional thyristor WTCW2 is connected to the step-down transformer winding w1, the other ends of the bidirectional thyristors WTCU2, WTCU2 and WTCW2 are respectively connected to one end of the three-phase protection switch, the other end of the three-phase protection switch is respectively connected to a of the low-voltage distribution transformer winding a, distribution transformer low-voltage winding b, distribution transformer low-voltage winding c. The three-phase input voltage, the current, the three-phase output voltage, the current and each group of voltage combined windings are connected to the main control system, the operating system and the driving system are connected to the main control system, the operating system is a touch screen operation interface, and the main control system controls the voltage combined windings to work through the driving system.

The working principle is as follows: when the power is on or the input voltage is equal to the rated voltage, the master control system controls the bidirectional thyristors WTCU2, WTCV2 and WTCW2 to be turned off, the bidirectional thyristors WTCU1, WTCV1 and WTCW1 are turned on at the same time, the step-down device windings u1 and u2 are short-circuited, the step-down device windings v1 and v2 are short-circuited, the step-down device windings w1 and w2 are short-circuited, the output voltage is equal to the current voltage value, when the input voltage is higher than the rated voltage, the master control system controls the bidirectional thyristors WTCU1, WTCV1 and WTCW1 to be turned off, the bidirectional thyristors WTCU2, WTCV2 and WTCW2 are turned on at the same time, the secondary winding group performs voltage cancellation on the primary winding group, and the output voltage is equal to the rated voltage value.

The present invention has been described in detail with reference to the specific embodiments, but these should not be construed as limitations of the present invention. Numerous variations and modifications can be made by those skilled in the art without departing from the principles of the invention, which should also be viewed as the protection of the invention.

Claims (4)

1. Class I power transformer step-down automatic voltage regulator device, its characterized in that: the transformer voltage stabilizing device comprises an Ii distribution transformer voltage stabilizing device, an Iii encapsulated coil transformer voltage stabilizing device, an Iiii split transformer voltage regulating device, an Iiv double-winding transformer voltage stabilizing device, an I v double-winding transformer automatic voltage regulating device and an I vi transformer voltage stabilizing device. The I i is a distribution transformer voltage stabilizing device, further comprises a distribution transformer and a plurality of groups of voltage reducers, and is applied to various voltage grade classifications, various cooling classifications, various shell classifications and various connection classifications and combination classifications except a series of automatic voltage stabilizing devices of power transformers described in the abstract specification. The distribution transformer further comprises a distribution transformer high-voltage winding A, a distribution transformer high-voltage winding B, a distribution transformer high-voltage winding C, a distribution transformer high-voltage winding Y, a distribution transformer low-voltage winding a, a distribution transformer low-voltage winding B, a distribution transformer low-voltage winding C, a distribution transformer low-voltage winding Y and a plurality of groups of distribution transformer tuning windings X1, a distribution transformer tuning winding X2, a distribution transformer tuning winding Y1, a distribution transformer tuning winding Y2, a distribution transformer tuning winding Z1 and a distribution transformer tuning winding Z2. The buck also includes a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2, a buck winding U1, a buck winding U2, a buck winding V1, a buck winding V2, a buck winding W1, a buck winding W2.

2. A distribution transformer regulating device according to claim 1, characterized in that: further comprising said distribution transformer tuning winding X1 connected to a distribution transformer tuning winding Y2, the distribution transformer tuning winding X2 is connected to a distribution transformer tuning winding Z1, the distribution transformer tuning winding Z2 is connected to a distribution transformer tuning winding Y1, the distribution transformer tuning winding X1 is further connected with a step-down transformer winding W1, the distribution transformer tuning winding Y1 is further connected with a step-down transformer winding V1, the distribution transformer tuning winding Z1 is also connected with a voltage reducer winding U1, the voltage reducer winding W1 is also connected with a voltage reducer winding V2, the voltage reducer winding V1 is also connected with a voltage reducer winding U2, the voltage reducer winding U1 is also connected with a voltage reducer winding W2, the step-down transformer winding u1 is connected to the step-down transformer winding w2, the step-down transformer winding u2 is connected to the step-down transformer winding v1, and the step-down transformer winding v2 is connected to the step-down transformer winding w 1.

3. A distribution transformer regulating device according to claim 2, characterized in that: the bidirectional protection circuit further comprises a bidirectional thyristor WTCU1, a bidirectional thyristor WTCU2, a bidirectional thyristor WTCV1, a bidirectional thyristor WTCV2, a bidirectional thyristor WTCW1, a bidirectional thyristor WTCW2 and a three-phase control protection switch, wherein the bidirectional thyristor WTCU1 is connected between a step-down transformer winding u1 and a step-down transformer winding u2, the bidirectional thyristor WTCV1 is connected between a step-down transformer winding v1 and a step-down transformer winding v2, the bidirectional thyristor WTCW1 is connected between a step-down transformer winding w1 and a step-down transformer winding w2, one end of the bidirectional thyristor WTCU2 is connected to the step-down transformer winding u1, one end of the bidirectional thyristor WTCCV 2 is connected to the step-down transformer winding v1, one end of the bidirectional thyristor WTCW2 is connected to the step-down transformer winding w1, the other ends of the bidirectional thyristors WTCU2, WTCV2 and WTCW2 are respectively connected to one end of the three-phase protection switch, the other end of the three-phase protection switch is respectively connected to a low-voltage distribution transformer winding a and a distribution transformer low-voltage winding b, and c, a low-voltage winding of the distribution transformer.

4. A distribution transformer regulating device according to claim 3, characterized in that: the three-phase input voltage, the current, the three-phase output voltage, the current and each group of voltage combined windings are connected to the main control system, the operating system and the driving system are connected to the main control system, the operating system is a touch screen operation interface, and the main control system controls the voltage combined windings to work through the driving system.

Images