CN206041510U - Intelligence electric capacitance device and reactive compensation system - Google Patents

Abstract

The application discloses an intelligent power capacitor device and a reactive power compensation system. The device includes a circuit breaker, a switching switch, a power capacitor and a control circuit; wherein, the first end of the circuit breaker is connected to the low-voltage bus, and the second end connected to the first end of the switching switch; the second end of the switching switch is connected to the power capacitor; the switching switch is also connected to the control circuit, and the control circuit is used to The state of the bus bar controls the opening or closing of the switching switch, and the reactive power compensation is performed on the low-voltage bus bar by using the power capacitor. The above intelligent power capacitor device and reactive power compensation system provided by the present application have the advantages of energy saving, integration, miniaturization and convenient installation, simple wiring, convenient expansion, simple maintenance, and improved operational reliability.

Description

An intelligent power capacitor device and reactive power compensation system

technical field

The utility model belongs to the technical field of electrical equipment, and more specifically relates to an intelligent power capacitor device and a reactive power compensation system.

Background technique

In order to ensure safe, high-quality, and reasonable operation of the power grid, reactive power compensation plays an important role. Installing high-quality and reliable reactive power compensation devices on the low-voltage side of the distribution network can improve the power factor of the power grid, reduce the loss of transformers and transmission lines, and ensure the power grid Power quality.

Generally speaking, the low-voltage reactive power compensation device is composed of reactive power compensation controllers, low-voltage power capacitors, fuses, contactors, and thermal relays. During operation, switching is likely to generate inrush currents, and AC contactors are noisy and The disadvantage of low reliability, and the wiring is complicated, takes up a lot of space, and is inconvenient to maintain.

Utility model content

In order to solve the above technical problems, the utility model provides an intelligent power capacitor device and a reactive power compensation system, which has the advantages of energy saving, integration, miniaturization and convenient installation, simple wiring, convenient expansion, simple maintenance, and improved operation reliability. sex.

An intelligent power capacitor device provided by the utility model includes a circuit breaker, a switching switch, a power capacitor and a control circuit;

Wherein, the first end of the circuit breaker is connected to the low-voltage bus, and the second end is connected to the first end of the switching switch;

The second end of the switching switch is connected to the power capacitor;

The switching switch is also connected to the control circuit, and the control circuit is used to control the opening or closing of the switching switch according to the state of the low-voltage bus, and use the power capacitor to perform reactive power on the low-voltage bus. compensate.

Preferably, in the above smart power capacitor device, the number of the power capacitors is three, and the three power capacitors are connected end to end and respectively connected to the three phases of the low voltage bus.

Preferably, in the above smart power capacitor device, there are two switching switches, which are respectively connected to any two phases of the three phases of the low-voltage bus.

Preferably, in the above-mentioned smart power capacitor device, the control circuit includes a first interface, and the first interface is connected to the low-voltage bus through a current transducer.

Preferably, in the above-mentioned smart power capacitor device, the control circuit further includes a second interface, and the second interface is used to connect to other smart power capacitor devices.

Preferably, in the above intelligent power capacitor device, a display circuit is also included for displaying current and voltage values, active power, reactive power, power factor, total voltage harmonic distortion rate and current temperature parameters in the capacitor.

Preferably, in the above-mentioned smart power capacitor device, an alarm component connected to the control circuit is also included for alarming when overvoltage, undervoltage, phase loss, harmonic overrun or temperature exceeds a predetermined threshold.

Preferably, in the above-mentioned smart power capacitor device, the control circuit includes a single-chip microcomputer and a current sampling component, a voltage transformer, a signal feedback component, a temperature sensor, a communication interface and a capacitor switching control component respectively connected to the single-chip microcomputer.

Preferably, in the above smart power capacitor device, a reactor connected between the switching switch and the power capacitor is further included.

A reactive power compensation system provided by the utility model includes a plurality of any one of the above-mentioned intelligent power capacitor devices, and the plurality of smart power capacitor devices are connected to each other and then connected to a low-voltage bus.

It can be seen from the above technical solutions that the smart power capacitor device and the reactive power compensation system provided by the utility model, since the smart power capacitor device includes a circuit breaker, a switching switch, a power capacitor and a control circuit; wherein, the circuit breaker The first end of the switching switch is connected to the low-voltage bus, and the second end is connected to the first end of the switching switch; the second end of the switching switch is connected to the power capacitor; the switching switch is also connected to the control circuit connection, the control circuit is used to control the opening or closing of the switching switch according to the state of the low-voltage bus, and use the power capacitor to perform reactive power compensation on the low-voltage bus, so it has the advantages of energy saving, integration and miniaturization And the advantages of convenient installation, simple wiring, convenient expansion, simple maintenance, and improve the reliability of operation.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description It is only an embodiment of the utility model, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

FIG. 1 is a schematic diagram of a first smart power capacitor device provided in an embodiment of the present application;

Fig. 2 is the synoptic diagram that two intelligent power capacitor devices operate in combination;

FIG. 3 is a schematic diagram of the composition of the control circuit of the eighth smart power capacitor device provided by the embodiment of the present application.

detailed description

The core idea of the utility model is to provide an intelligent power capacitor device and reactive power compensation system, which has the advantages of energy saving, integration, miniaturization and convenient installation, simple wiring, convenient expansion, simple maintenance and improved operation reliability.

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

The first smart power capacitor device provided in the embodiment of the present application is shown in FIG. 1 , which is a schematic diagram of the first smart power capacitor device provided in the embodiment of the present application. The device includes a circuit breaker 1, a switching switch 2, a power capacitor 3 and a control circuit 4;

Wherein, the first end of the circuit breaker 1 is connected to the low-voltage bus 5, and the second end is connected to the first end of the switching switch 2. It should be noted that the circuit breaker can be a miniature circuit breaker, such as a common small Circuit switch, as a power switch and a protection switch for power capacitors;

The second end of the switching switch 2 is connected to the power capacitor 3. It should be noted that the power capacitor is used to provide reactive power consumed by inductive loads and reduce the inductive load of the grid power supply;

The switching switch 2 is also connected to the control circuit 4, and the control circuit 4 is used to control the opening or closing of the switching switch 2 according to the state of the low-voltage bus 5, and the power capacitor 3 is used to control the It should be noted that the control circuit obtains a series of parameter information of the current line through calculation, including line voltage, current, power factor, system reactive power, etc., and at the same time receives the information of the communication line and Instructions, instructions on capacitor operating status (manual/automatic), etc., after integrating the above information, make a judgment on whether the capacitor is switched or not.

The intelligent power capacitor device combines various components, which can be operated independently by a single unit or in a network of multiple units, and can replace the scattered fuses, switching switches and controllers installed in the original reactive power compensation device.

It can be seen from the above technical solutions that the first intelligent power capacitor device provided in the embodiment of the present application includes a circuit breaker, a switching switch, a power capacitor and a control circuit; wherein, the first end of the circuit breaker is connected to A low-voltage bus, the second end of which is connected to the first end of the switching switch; the second end of the switching switch is connected to the power capacitor; the switching switch is also connected to the control circuit, and the control circuit It is used to control the opening or closing of the switching switch according to the state of the low-voltage bus, and use the power capacitor to perform reactive power compensation on the low-voltage bus, so it has the advantages of energy saving, integration, miniaturization and convenient installation. The connection is simple, the expansion is convenient, the maintenance is simple, and the reliability of the operation is improved.

The second smart power capacitor device provided in the embodiment of the present application, on the basis of the above-mentioned first smart power capacitor device, also includes the following technical features:

The number of the power capacitors is three, and the three power capacitors are respectively connected to the three-phases of the low-voltage bus bar after being connected end to end, that is, the delta connection method is adopted. Of course, this is only a preferred solution, and it can also be used The star connection method will not be repeated here.

The third smart power capacitor device provided in the embodiment of the present application, on the basis of the above-mentioned second smart power capacitor device, also includes the following technical features:

There are two switching switches, which are respectively connected to any two phases of the three phases of the low-voltage bus.

That is to say, when the power capacitor adopts the "delta" connection method, when only one phase switching switch is turned on, the three-phase capacitors are not connected to the grid. Utilizing this feature, only two switching switches need to be installed on two phases when switching the common compensation capacitor. Using this "two control three" switching method can reduce one switching switch, effectively reducing the cost of the product.

The fourth smart power capacitor device provided in the embodiment of the present application, on the basis of the above-mentioned first smart power capacitor device, also includes the following technical features:

The control circuit includes a first interface, and the first interface is connected to the low-voltage bus through a current transducer.

It should be noted that the current transducers in the prior art are external. Usually, a set of smart power capacitor devices is equipped with a current transducer. In this solution, the device is connected to the current transmitter, and the current value of the secondary side of the bus current transformer is sampled by the current transmitter, and the current signal is converted into a voltage signal, which can be connected to the smart power capacitor device through a separate transmission line .

The fifth smart power capacitor device provided in the embodiment of the present application, on the basis of the above-mentioned fourth smart power capacitor device, also includes the following technical features:

The control circuit also includes a second interface for connecting to other smart power capacitor devices.

Referring to FIG. 2, FIG. 2 is a schematic diagram of the combined operation of two smart power capacitor devices. It can be seen that the first smart power capacitor device on the left uses its second interface 201 to connect to the second smart power capacitor device on the right. An interface 202 realizes the cooperative work of two smart power capacitor devices. In addition, it can be seen from the first intelligent power capacitor device on the left in Figure 2 that the low-voltage buses L1, L2 and L3 are respectively connected to the first interface of the device through current transducers, and are also connected to the circuit breaker 1QF, The circuit breaker includes UA, UB and UC located on three phases, where the other end of UA is connected to a switching switch 1KA1, and the other end of UC is connected to another switching switch 1KA2. It should be noted that this is just an example , you can also connect the switching switch at the other end of UA and UC, or connect the switching switch at the other end of UB and UC. power capacitor, and the other end of another switching switch 1KA2 is also connected to the power capacitor. In this embodiment, three power capacitors in delta connection are used to realize the connection with two switching switches, and in the control circuit Under the control of the low-voltage bus, it can perform reactive power compensation on the low-voltage busbar, and can be used in combination with other devices. The specific number can be determined according to actual needs, which is not limited here. In addition, other interfaces HL1, HL2 and HL3 are also included. Can be used to connect to other devices.

The sixth smart power capacitor device provided in the embodiment of the present application, on the basis of any one of the above-mentioned first to fifth smart power capacitor devices, also includes the following technical features:

It also includes a display circuit, which is used to display current and voltage values, active power, reactive power, power factor, voltage harmonic total distortion rate and current temperature parameters in the capacitor, which allows people to intuitively understand the current parameters of the low-voltage bus situation, and can monitor the reactive power compensation effect of the device.

The seventh smart power capacitor device provided in the embodiment of the present application, on the basis of the sixth smart power capacitor device above, also includes the following technical features:

It also includes an alarm component connected with the control circuit, which is used for alarming when overvoltage, undervoltage, phase loss, harmonic overrun or temperature exceeds a predetermined threshold. In this case, it is possible to deal with the abnormal situation in time, disconnect the switching switch, make the capacitor out of operation, and avoid a more serious situation.

The eighth smart power capacitor device provided in the embodiment of the present application, on the basis of any one of the above-mentioned first to fifth smart power capacitor devices, also includes the following technical features:

Referring to FIG. 3 , FIG. 3 is a schematic composition diagram of a control circuit of an eighth smart power capacitor device provided in an embodiment of the present application. The control circuit includes a single-chip microcomputer 301 and a current sampling part 302, a voltage transformer 303, a signal feedback part 304, a temperature sensor 305, a communication interface 306 and a capacitor switching control part 307 respectively connected to the single-chip microcomputer 301.

In this case, the capacitor switching control part switches the capacitor according to the signal of the single-chip microcomputer. In order to reduce the surge current and overvoltage, the single-chip microcomputer can control the phases, and take advantage of the advantages of fast sampling, analysis calculation and data storage of the microcontroller. , taking full account of the time from when the actuator is commanded (energized) to when the action is completed (contact closure or the opposite), so that the contacts of the switching switch are closed when the voltage crosses zero and open when the current crosses zero. Thereby avoiding the damage of transient overvoltage and surge current to the contacts, and reducing the wear of the contacts. The signal feedback components mainly include manual/automatic control switching and parameter setting functions. The main setting parameters include capacitance value, current transformer ratio, input delay, input interval, power factor lower limit, overvoltage value, undervoltage value, harmonic Wave voltage exceeding limit value, high temperature alarm value, etc. The communication interface mainly completes the current signal reception of the current transmitter and the communication of each intelligent power capacitor device.

The ninth smart power capacitor device provided in the embodiment of the present application, on the basis of any one of the above-mentioned first to fifth smart power capacitor devices, also includes the following technical features:

A reactor connected between the switching switch and the power capacitor is also included.

A reactive power compensation system provided by an embodiment of the present application includes a plurality of any one of the above-mentioned intelligent power capacitor devices, and the plurality of smart power capacitor devices are connected to each other and then connected to a low-voltage bus.

In the specific engineering design, the total capacitance needs to be compensated according to the engineering calculation, and reasonable grouping can be carried out. If the compensation capacity is 750kvar, it can be divided into 15 sets of 40kvar and 5 sets of 30kvar intelligent power capacitor devices. One of them is set as the master, and the other 19 are slaves. Each smart power capacitor device samples independently and transmits the data to the host for analysis. The host issues control commands to control the orderly switching of 20 smart power capacitor devices to achieve the purpose of reactive power compensation for the grid. When the slave machine fails, it will automatically exit the compensation system without affecting the work of other intelligent power capacitors; when the master machine fails, it will also automatically exit the compensation system, and the remaining slave machines will automatically generate a master again. If any intelligent power capacitor device fails, whether it is the master or the slave, the entire reactive power compensation system only reduces the compensation capacity and does not affect normal operation, avoiding the paralysis of the entire compensation system once the controller in the traditional reactive power compensation system is damaged. Case.

In summary, the smart power capacitor device provided by the embodiment of the present application adopts a building block structure, which is easy to connect, easy to expand, easy to maintain, and adopts integrated technology. 80% of the contacts, the cabinet is simple, and each device in the above-mentioned reactive power compensation system can operate independently or in a network, which improves the reliability of operation.

The above description of the disclosed embodiments enables those skilled in the art to realize or use the utility model. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. a kind of intelligent electric power capacitive means, it is characterised in that including chopper, fling-cut switch, power capacitor and control electricity Road；

Wherein, the first end of the chopper is connected to low-voltage bus bar, and the second end connects the first end of the fling-cut switch；

Second end of the fling-cut switch is connected to the power capacitor；

The fling-cut switch is also connected with the control circuit, and the control circuit is for the state control according to the low-voltage bus bar Being turned on and off for the fling-cut switch is made, reactive-load compensation is carried out to the low-voltage bus bar using the power capacitor.

2. intelligent electric power capacitive means according to claim 1, it is characterised in that the quantity of the power capacitor is three It is individual, and be connected with the three of the low-voltage bus bar after three power capacitors are end to end respectively.

3. intelligent electric power capacitive means according to claim 2, it is characterised in that the quantity of the fling-cut switch is two It is individual, and connect any biphase in the three-phase of the low-voltage bus bar respectively.

4. intelligent electric power capacitive means according to claim 1, it is characterised in that the control circuit includes that first connects Mouthful, the first interface is connected to the low-voltage bus bar by current transducer.

5. intelligent electric power capacitive means according to claim 4, it is characterised in that the control circuit is also connect including second Mouthful, the second interface is used for being connected to other intelligent electric power capacitive means.

6. intelligent electric power capacitive means according to any one of claim 1-5, it is characterised in that also including display circuit, For showing in current/voltage value, active power, reactive power, power factor, total harmonic distortion and capacitance present device Temperature parameter.

7. intelligent electric power capacitive means according to claim 6, it is characterised in that also include being connected with the control circuit Warning piece, for when over-pressed, under-voltage, phase shortage, harmonic wave transfinite or temperature exceed predetermined threshold when reported to the police.

8. intelligent electric power capacitive means according to any one of claim 1-5, it is characterised in that the control circuit includes Single-chip microcomputer and the current sample part being connected with the single-chip microcomputer respectively, voltage transformer, signal feedback element, temperature sensing Device, communication interface and capacitor switching control unit.

9. intelligent electric power capacitive means according to any one of claim 1-5, it is characterised in that also described including being connected to Reactor between fling-cut switch and the power capacitor.

10. a kind of reactive compensation system, it is characterised in that including multiple intelligent electric powers as described in any one of claim 1-9 Capacitive means, multiple intelligent electric power capacitive means are connected with low-voltage bus bar after being connected with each other.