CN216848079U - Single-phase input and three-phase input equal-power load - Google Patents

Abstract

The utility model provides a power load such as single-phase input and three-phase input, includes binding post L1, L2, L3, N to and first relay, second relay, third relay, load branch road. The load branch comprises three resistors with the same resistance, one ends of the three resistors are respectively connected to the wiring terminals L1, L2 and L3 through the switches 1KM, and the other ends of the three resistors are connected to the wiring terminal N in common; the first relay is provided with three normally open contacts KM1, one ends of the three normally open contacts KM1 are respectively connected with a wiring terminal L1, a wiring terminal L2 and a wiring terminal L3, and the other ends of the three normally open contacts KM1 are connected in common; one end of a coil KA1 of the second relay is connected with a wiring terminal L1, one end of a coil KA2 of the third relay is connected with a wiring terminal L3, the other ends of the coils KA1 and KA2 are connected with the wiring terminal L2 after being connected in parallel, the second relay is provided with a normally closed contact KA1, the third relay is provided with a normally closed contact KA2, the normally closed contacts KA1 and KA2 are connected in parallel, one end of the normally closed contacts KA1 and KA2 is connected with one of the wiring terminals L1, L2 and L3, and the other end of the normally closed contact KA1 and KA2 is connected with a wiring terminal N through a coil KM1 of the first relay.

Description

Single-phase input and three-phase input equal-power load

Technical Field

The utility model relates to the field of loads, in particular to a single-phase input and three-phase input equal-power load.

Background

In practical application test of the load, it may be encountered that some power supplies to be tested require three-phase input and single-phase input, and the load can be loaded with the same power, for example, the voltage of the power supply to be tested is U1 three-phase, the load system can be loaded with P1 when the system requires three-phase input, and the load system can also be loaded with P1 when the input is single-phase and the voltage is U1/1.732. In order to solve the above-mentioned requirements, the present invention provides a new load design scheme to realize and satisfy the above-mentioned load requirements.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a power load with single-phase input, three-phase input and the like.

In order to achieve the purpose, the equal-power load with single-phase input and three-phase input comprises three-phase four-wire connecting terminals L1, L2, L3 and N, a first relay, a second relay, a third relay and at least one load branch circuit;

the load branch comprises three metal resistors with the same resistance, one ends of the three metal resistors are respectively connected to the wiring terminals L1, L2 and L3 through the switches 1KM, and the other ends of the three metal resistors are connected to the wiring terminal N in common;

the first relay is provided with three normally open contacts KM1, one ends of the three normally open contacts KM1 are respectively connected with a wiring terminal L1, a wiring terminal L2 and a wiring terminal L3, and the other ends of the three normally open contacts KM1 are connected in common;

Binding post L1 is connected to coil KA1 one end of second relay, binding post L3 is connected to coil KA2 one end of third relay, and connecting post L2 is connected after the other end of coil KA1, KA2 connects altogether, and the second relay has normally closed contact KA1, and the third relay has normally closed contact KA2, and one of binding post L1, L2, L3 is connected to one end after normally closed contact KA1, KA2 both connect in parallel, and the other end is connected to binding post N through the coil KM1 of first relay.

Further, the switch 1KM is a contactor, and the single-phase input and three-phase input equal-power loads are provided with controllers respectively connected with the contactor.

Furthermore, the single-phase input and three-phase input equal-power loads are provided with three-phase electric control main switches 1QF which are respectively connected with the wiring terminals L1, L2 and L3 in series, and the three-phase electric control main switches 1QF are connected with the controller.

Furthermore, the load branch circuit has a plurality of load branch circuits, and the resistance values of the metal resistors in each load branch circuit are different.

Furthermore, one end of each of the three metal resistors is connected to a connection terminal L1, a connection terminal L2, and a connection terminal L3 through a switch 1KM and a fuse, respectively.

According to the power load with the single-phase input, the three-phase input and the like, when the voltage input is three-phase U1 or single-phase voltage U1/1.732, the load system can always load a certain specified power, and the load can load the same power when the three-phase input and the single-phase input are realized.

The above description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following detailed description of the present invention is provided.

Drawings

Various additional advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the utility model. Also, like reference numerals are used to designate like parts throughout the drawings.

In the drawings:

fig. 1 shows the electrical topology of single-phase input and three-phase input equal power loads of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

As the three phases 380v and 50HZ are used for supplying power for China and most of electrical components are suitable for the voltage level, the three phases are listed as a class for description.

In this embodiment, the electrical topology of the power load with single-phase input and three-phase input is as shown in fig. 1, where:

l1, L2, L3 and N are connecting terminals of an external three-phase four-wire power supply to be tested, wherein L1, L2 and L3 correspond to A, B, C three phases respectively;

1QF is a three-phase electric control main switch used for controlling the on-off of a main loop;

KM1 is a first relay for controlling three-phase/single-phase automatic switching, and is disconnected in the case of three phases and is attracted in the case of single phase;

KA1 and KA2 are respectively a first relay and a second relay, and the coil voltage is AC380 v;

(1-n) FUa-c is a fuse used for overcurrent protection of the resistor;

(1-n) KM is a gear contactor, is used for switching a load and can be replaced by other switches;

and (1-n) Ra-c are metal resistors and are mainly used for active power consumption.

In this embodiment, the single-phase input and three-phase input equal-power loads further include a controller, and the gear contactor and the three-phase electric control main switch are respectively connected to the controller to realize electric control.

Specifically, the connection relationship among the above devices is as follows:

the load branch circuits are provided with a plurality of load branch circuits, the resistance values of metal resistors in the load branch circuits are different, switching of the multi-gear resistors is achieved, and the load branch circuits are identical in topological structure. For each load branch, the core is composed of three metal resistors with the same resistance value, taking the first load branch as an example, one ends of the three metal resistors are respectively connected to the wiring terminals L1, L2 and L3 through the gear contactor 1KM and the fuse, and the other ends of the three metal resistors are connected to the wiring terminal N in common.

The three-phase electric control main switch 1QF is respectively connected with the wiring terminals L1, L2 and L3 in series to realize input main control.

A relay has three normally open contact KM1, binding post L1 is connected respectively to three normally open contact KM 1's one end, L2, L3, the other end connects jointly, binding post L1 is connected to the coil KA1 one end of second relay, binding post L3 is connected to the coil KA2 one end of third relay, coil KA1, the other end of KA2 connects after connecting jointly and connects binding post L2, the second relay has normally closed contact KA1, the third relay has normally closed contact KA2, normally closed contact KA1, one of binding post L1 is connected to both parallelly connected back one end of KA2, L2, L3, the other end is connected to binding post N through the coil KM1 of first relay.

When the three phases are connected:

when an external three-phase power supply is connected to L1, L2, L3 and N, buses A, B and C are electrified after a main switch 1QF is switched on, so that the intermediate relays KA1 and KA2 are attracted at the same time, normally closed contacts of KA1 and KA2 act to be disconnected, a coil of the voltage switching contactor KM1 is not electrified, and a main contact of KM1 is in a disconnected state.

At this time, if the 1 KM-position contactor is put into operation, the resistors 1Ra, 1Rb and 1Rc are put into operation, the resistances of the resistors 1Ra, 1Rb and 1Rc are equal, the power is the same, and the total power P1 put into the 1 KM-position contactor is 3 × 220/Ra

When the single phase is connected:

when an external single-phase power supply is connected to any one of copper plates and N of L1, L2 and L3, after a main switch 1QF is switched on, the intermediate relays KA1 and KA2 are not attracted, a voltage switching contactor KM1 coil is electrified, and a KM1 main contact is attracted, so that the original three copper plates A, B and C have 220v voltage at the same time.

At this time, if a 1KM tap contactor is put into operation, the resistors 1Ra, 1Rb and 1Rc are put into operation, and the total power P2 put into the 1KM tap contactor is 3 × 220/Ra.

Therefore, no matter single-phase or three-phase connection is adopted, power P1 is equal to P2, and the same applies to gears 2 to nKM.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the utility model may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Claims (5)

1. The power load with single-phase input, three-phase input and the like is characterized by comprising three-phase four-wire connecting terminals L1, L2, L3 and N, a first relay, a second relay, a third relay and at least one load branch circuit;

the load branch comprises three metal resistors with the same resistance, one ends of the three metal resistors are respectively connected to the wiring terminals L1, L2 and L3 through the switches 1KM, and the other ends of the three metal resistors are connected to the wiring terminal N in common;

The first relay is provided with three normally open contacts KM1, one ends of the three normally open contacts KM1 are respectively connected with a connecting terminal L1, a connecting terminal L2 and a connecting terminal L3, and the other ends of the three normally open contacts are connected together;

binding post L1 is connected to coil KA1 one end of second relay, binding post L3 is connected to coil KA2 one end of third relay, coil KA1, KA 2's the other end connects back connection binding post L2 altogether, the second relay has normally closed contact KA1, the third relay has normally closed contact KA2, one of them binding post L1, L2, L3 is connected to one end after normally closed contact KA1, KA2 are parallelly connected, the other end is connected to binding post N through first relay's KM coil 1.

2. The single phase input and three phase input equal power load of claim 1, wherein: the switch 1KM is a contactor, and the single-phase input and three-phase input equal-power loads are provided with controllers which are respectively connected with the contactor.

3. The single phase input and three phase input equal power load of claim 2, wherein: the single-phase input and three-phase input equal-power load is provided with a three-phase electric control main switch 1QF which is respectively connected with a wiring terminal L1, a wiring terminal L2 and a wiring terminal L3 in series, and the three-phase electric control main switch 1QF is connected with the controller.

4. The single-phase input and three-phase input equal power load of claim 2, wherein: the load branch circuit is provided with a plurality of load branch circuits, and the resistance values of the metal resistors in the load branch circuits are different.

5. The single-phase input and three-phase input equal power load of claim 1, wherein: one ends of the three metal resistors are connected to connecting terminals L1, L2 and L3 through a switch 1KM and a fuse respectively.

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