CN205544306U - Low -voltage capacitor compensation cabinet - Google Patents

Abstract

The utility model discloses a low -voltage capacitor compensation cabinet aims at providing a reduce cost, the wiring is simple, the structure is simplified, the security performance is high low -voltage capacitor compensation cabinet, has solved among the prior art extravagant seriously to contactor switch contact, and the incomplete problem of security performance, its technical scheme main points are including three -phase inlet wire end, switch contact, reactor and the condenser of the isolator who establishes ties with three -phase inlet wire end, first fuse, contactor, low -voltage capacitor compensation cabinet still includes the pilot lamp, the pilot lamp connects in parallel on the condenser, electric current indicating units and voltage indicating units still have been coupled between isolator and the fuse, electric current indicating units is including the current transformer of response inlet wire electric current and the ampere meter of connecting current transformer, the unit is including the voltage conversion switch of selecting the arbitrary looks incoming line ports of three -phase electricity, the voltmeter of connecting the voltage conversion switch.

Description

Low voltage capacitor compensation cabinet

technical field

The utility model relates to electrical equipment, in particular to a low-voltage capacitance compensation cabinet.

Background technique

The existing low-voltage capacitor cabinets are mainly composed of cabinet shells, busbars, circuit breakers, isolating switches, thermal relays, contactors, lightning arresters, capacitors, reactors, primary and secondary wires, terminal blocks, power factor compensation control devices, panel instruments, etc. composition. However, the existing low-voltage capacitor cabinets have defects such as cumbersome production process, heavy workload, many nodes, high cost, heavy weight, and many hidden trouble points; The current-limiting impedance of the special contactor and the phenomenon that the main contact is burned out occur from time to time.

Among them, the commonly used circuit of the low-voltage capacitor cabinet is shown in Figure 1-2. In the main circuit of Figure 1, the capacitor compensation part is connected to the three-phase power grid. The capacitance compensation part is provided with multiple groups, and one of the seven groups is shown in the figure, so that the cost of the number of contactors increases accordingly. In Figure 2, the interface of the control circuit is connected to the coil part of the contactor, and a rotary switch SA is set for function selection. The indicator module 4 shown in the indicator module 4 uses a switch contact of a contactor KM in series with an indicator light HD to indicate the working condition of the contactor KM, but the cost of this structural design is relatively high, and the waste of the contactor switch contacts is serious, so How to improve the safety performance under the condition of guaranteeing the cost is a problem that needs to be solved.

Utility model content

Aiming at the deficiencies in the prior art, the purpose of the utility model is to provide a low-voltage capacitor compensation cabinet with reduced cost, simple wiring, simplified structure and high safety performance.

The above-mentioned technical purpose of the utility model is achieved through the following technical solutions: a low-voltage capacitor compensation cabinet, including a three-phase incoming line terminal, an isolating switch connected in series with the three-phase incoming line terminal, a first fuse, and a switch for a contactor Contacts, reactors and capacitors, the low-voltage capacitance compensation cabinet also includes an indicator light, the indicator light is connected in parallel to the capacitor, and a current indicating unit and a voltage indicating unit are also coupled between the isolating switch and the fuse, so The current indicating unit includes a current transformer for inducting incoming line current and an ammeter connected to the current transformer; the voltage indicating unit includes a voltage transfer switch for selecting any one phase incoming line port of three-phase electricity, and a voltmeter connected to the voltage transfer switch .

Through the above scheme, compared with the existing indicating module, the setting of the indicator light saves the use of the switch contacts of the corresponding contactor, simplifies the circuit wiring structure, and reduces the cost of selecting the contactor, because the contactor contacts are more The more expensive the price, the higher the cost, and the setting of the indicator light connected to the capacitor in parallel can directly judge the working status through the working status of the contactor switch on the main circuit, thereby improving the practicability of the circuit. At the same time, the voltage The setting of the indicating unit and the current indicating unit further improves the monitoring and judgment of the working state of the circuit, and the staff can intuitively know the voltage and current of the circuit, which improves the safety performance. Further, a voltmeter is used for indicating the voltage. The phase voltage to be displayed is selected through the voltage conversion switch, thereby saving part of the cost of the voltmeter.

As a specific solution of the present invention, it may be preferred that: the inlet end of the voltage conversion switch is further connected with a second fuse.

Through the above solution, the second fuse can effectively prevent damage to the voltmeter, and when an overcurrent occurs, the second fuse can be blown directly, thereby protecting the voltage conversion switch and the voltmeter in the subsequent stage.

As a specific solution of the present invention, it may be preferred that the low-voltage capacitor compensation cabinet further includes a temperature controller, a temperature control switch connected to the temperature controller, and a cooling fan connected to the temperature control switch.

Through the above scheme, the setting of the controller can keep the temperature in the switchgear more suitable. Since capacitors and reactors are devices with serious heat generation, the increase of the working environment temperature will cause serious damage to the service life of the respective devices. Unfavorable effects, this structure can ensure that the switchgear can effectively cool down and improve the service life of the device.

As a specific solution of the utility model, it can be preferably: the cooling fan is provided with a main fan and a backup fan, the power supply circuit of the main fan is provided with a thermal relay, and the power supply circuit of the backup fan is provided with the thermal relay normally open contacts.

Through the above scheme, the main fan and the backup fan are set up, thereby improving the overall service life and reliability of use. When the main fan fails, the backup fan can also be used to work, thereby effectively maintaining the normal operation of the switch cabinet; When the relay detects that the main fan fails to work, its normally open contact will close, thereby switching to the standby fan operation mode.

To sum up, the utility model has the following beneficial effects: the cost effectively reduces the component selection of the switch cabinet, simplifies the circuit structure, and ensures the working safety and service life of the switch cabinet.

Description of drawings

Fig. 1 is the main circuit in the prior art;

Fig. 2 is the control circuit in the prior art;

Fig. 3 is the main circuit of the present embodiment;

Fig. 4 is the current indicating unit of the present embodiment;

Fig. 5 is the voltage indicating unit of the present embodiment;

Fig. 6 is a circuit connection diagram of the thermostat of this embodiment.

In the figure 1. Three-phase incoming line terminal; 2. Current indicating unit; 3. Voltage indicating unit; 4. Indicating module; QS, isolating switch; FU1, first fuse; KM1, contactor; L1, reactor; C1 , capacitor; HD, indicator light; TA, current transformer; A, ammeter; SV, voltage transfer switch; V, voltmeter; FU2, second fuse; WK, temperature controller; ZJ, temperature control switch; FAN1, Main fan; FAN2, spare fan; KH, thermal relay.

detailed description

Below in conjunction with accompanying drawing, the utility model is described in further detail.

Embodiment: Referring to Figure 3-5, a low-voltage capacitor compensation cabinet includes a three-phase incoming line terminal 1, an isolating switch QS connected in series with the three-phase incoming line terminal 1, a first fuse FU1, and a switch contact of a contactor KM1 , reactor L1 and capacitor C1, the low-voltage capacitance compensation cabinet also includes an indicator light HD, the indicator light HD is connected in parallel to the capacitor C1, and a current indicating unit 2 and a current indicating unit 2 are also coupled between the isolating switch QS and the fuse A voltage indication unit 3, the current indication unit 2 includes a current transformer TA that senses incoming current and an ammeter A connected to the current transformer TA; A voltage conversion switch SV, and a voltmeter V connected to the voltage conversion switch SV. Among them, a lightning arrester BL is also installed at the incoming line interface. The lightning arrester can reduce the grid current interference caused by direct lightning or induced lightning, and reduce the hazards of equipment use. Referring to FIG. 2 , the structure of the indicating module 4 in the control circuit in this embodiment can be omitted, thereby reducing the cost.

In FIGS. 4 and 5 , the inlet port of the voltage conversion switch SV is also connected to a second fuse FU2 . The connection mode of the left and right contacts of the voltage conversion switch SV is shown in FIG. 4 , and the left and right contacts can be selectively connected by toggling the voltage conversion switch SV. For the three-phase electrical interface in the current indication unit 2, the output ports of each current transformer TA in the figure are A401, B401, and B401 respectively, and the ammeter A is connected in series with the neutral line N401.

Compared with the existing indicator module 4, the setting of the indicator light HD saves the use of the switch contacts of the corresponding contactor KM1, simplifies the circuit wiring structure, and reduces the cost of selecting the contactor KM1, because the contacts of the contactor KM1 The more it is, the more expensive the price is, and the higher the cost is, and the indicator HD is connected in parallel to the capacitor C1, and the working state can be judged directly through the working condition of the contactor KM1 switch on the main circuit, thereby improving the practicability of the circuit. At the same time, the setting of the voltage indication unit 3 and the current indication unit 2 further improves the monitoring and judgment of the working state of the circuit, the staff can intuitively know the voltage and current of the circuit, and improve the safety performance. Further, the voltage indication adopts A voltmeter V is used for indication, and the phase voltage to be displayed is selected through the voltage conversion switch SV, thereby saving a part of the cost of the voltmeter V. The second fuse FU2 can effectively prevent damage to the voltmeter V. When an overcurrent occurs, the second fuse FU2 can be blown directly, thereby protecting the voltage conversion switch SV and the voltmeter V in the subsequent stage.

As shown in Figure 6, the low-voltage capacitor compensation cabinet also includes a temperature controller WK, a temperature control switch ZJ connected to the temperature controller WK, and a cooling fan connected to the temperature control switch ZJ. The cooling fan is provided with a main fan FAN1 and a backup fan FAN2, the power supply circuit of the main fan FAN1 is provided with a thermal relay KH, and the power supply circuit of the backup fan FAN2 is provided with a normally open contact of the thermal relay KH. The power supply of the thermostat WK is taken from any phase of the three-phase grid, and the fuse element can also be connected in series. The thermostat WK can automatically output the switching signal according to the temperature, so that the temperature control switch ZJ is closed when it is high temperature, and the temperature control switch ZJ is closed when it is low temperature. When it is disconnected, the main fan FAN1 can work at high temperature to cool down.

The setting of the controller, so that the temperature in the switch cabinet can be kept more appropriate. Since the capacitor C1 and the reactor L1 are devices with serious heat generation, the increase of the working environment temperature will cause adverse effects on the service life of the respective devices. Therefore, the structure can ensure that the switchgear can effectively cool down and improve the service life of the device. The main fan FAN1 and backup fan FAN2 are set to improve the overall service life and reliability of use. When the main fan FAN1 fails, the backup fan FAN2 can also be used to work, thereby effectively maintaining the normal operation of the switchgear; When the relay KH detects the failure of the main fan FAN1, its normally open contact will be closed, thereby switching to the working mode of the backup fan FAN2.

This specific embodiment is only an explanation of the utility model, and it is not a limitation of the utility model. After reading this description, those skilled in the art can make modifications to the embodiment without creative contribution according to needs, but as long as it is within the utility model All new claims are protected by patent law.

Claims (4)

1. A low-voltage capacitor compensation cabinet, comprising a three-phase incoming line terminal (1), an isolating switch (QS), a first fuse (FU1), and a contactor (KM1) connected in series with the three-phase incoming line terminal (1). Switch contacts, reactor (L1) and capacitor (C1), characterized in that: the low-voltage capacitor compensation cabinet also includes an indicator light (HD), and the indicator light (HD) is connected in parallel to the capacitor (C1), the A current indication unit (2) and a voltage indication unit (3) are also coupled between the isolating switch (QS) and the fuse, and the current indication unit (2) includes a current transformer (TA) that senses incoming current and a connection The ammeter (A) of the current transformer (TA); the voltage indication unit (3) includes a voltage conversion switch (SV) for selecting any one phase incoming line port of the three-phase electricity, a voltmeter connected to the voltage conversion switch (SV) (V). 2. The low-voltage capacitor compensation cabinet according to claim 1, characterized in that: the inlet port of the voltage conversion switch (SV) is also connected with a second fuse (FU2). 3. The low-voltage capacitor compensation cabinet according to claim 2, characterized in that: the low-voltage capacitor compensation cabinet also includes a thermostat (WK), a temperature control switch (ZJ) connected to the thermostat (WK), and The cooling fan connected to the temperature control switch (ZJ). 4. The low-voltage capacitor compensation cabinet according to claim 3, characterized in that: the cooling fan is provided with a main fan (FAN1) and a backup fan (FAN2), and the power supply circuit of the main fan (FAN1) is provided with a heat sink. Relay (KH), the power supply circuit of the standby fan (FAN2) is provided with a normally open contact of the thermal relay (KH).