Patent Application
20140185171
This application claims all benefits accruing under 35 U.S.C. §119 from China Patent Application No. 201210589364.9, filed on Dec. 29, 2012 in the State Intellectual Property Office of China. The contents of the China Application are hereby incorporated by reference.
1. Technical Field
The disclosure generally relates to power control apparatuses and methods, and particularly relates to three-phase AC power control apparatuses and methods.
2. Description of Related Art
A three-phase power system is often used to power large motors and other heavy loads. The three-phase power system is more economical than a single-phase or a two-phase power system at an equivalent voltage level because the three-phase power system uses less conductor material to transmit electrical power. However, some problems, such as a phase sequence error and a phase loss, often occur in the three-phase power system. Such problems may lead to a failure of the equipment and may cause irreversible damages.
Therefore, there is room for improvement within the art.
Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views.
The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like reference numerals indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean “at least one.”
In general, the word “module,” as used herein, refers to logic embodied in hardware or firmware, or to a collection of software instructions, written in a programming language such as Java, C, or assembly. One or more software instructions in the modules may be embedded in firmware, such as in an erasable-programmable read-only memory (EPROM). The modules described herein may be implemented as either software and/or hardware modules and may be stored in any type of non-transitory computer-readable medium or other storage device. Some non-limiting examples of non-transitory computer-readable media are compact discs (CDs), digital versatile discs (DVDs), Blu-Ray discs, Flash memory, and hard disk drives.
An input terminal of the three-phase power control apparatus 20 is connected to a three-phase power supply 10. An output terminal of the three-phase power control apparatus is connected to a load 30. The load 30 may be a motor, an industrial air conditioner or other electronic device.
An input terminal of the first circuit breaker QF1 is connected to an output terminal of the second circuit breaker QF2. An input terminal of the second circuit breaker QF2 is connected to the three-phase power supply 10. An output terminal of the first circuit breaker QF1 is connected to the load 30.
An input terminal of the third circuit breaker QF3 is connected to the output terminal of the circuit breaker QF2. An output terminal of the third circuit breaker QF3 is connected to an input terminal of the three-phase power monitor 21.
The three-phase power monitor 21 monitors three phase voltages provided by the three-phase power supply 10. An output terminal of the three-phase power monitor 21 is connected to the power supply controller 22 and the first notification device 23. When the three-phase power monitor 21 detects an error in the three phase voltages provided by the three-phase power supply 10, the three-phase power monitor 21 transmits a voltage signal to the power supply controller 22 and the first notification device 23.
The power supply controller 22 is connected to the output terminal of the second circuit breaker QF2 and may receive one of three phase voltages from the three-phase power supply 10. The power supply controller 22 is connected to a control terminal of the first circuit breaker QF1. When the power supply controller 22 receives a voltage signal from the three-phase power monitor 21, the power supply controller 22 controls the first circuit breaker QF1 to disconnect the load 30 from the three-phase power supply 10.
When the first notification device 23 receives a voltage signal from the three-phase power monitor 21, the first notification device 23 makes a public announcement to inform the proximate persons of the need to take action, for example, to cut off the three-phase power supply 10. In one embodiment, the first notification device 23 may include a strobe light which flashes light when the first notification device 23 receives the voltage signal from the three-phase power monitor 21. In some other embodiments, the first notification device 23 may include a speaker which sounds alarms when the first notification device 23 receives the voltage signal from the three-phase power monitor 21.
In some embodiments, when the first notification device 23 receives a voltage signal from the three-phase power monitor 21, the first notification device 23 transmits an alarm signal to a remotely located monitoring station 20 via an Internet Protocol (IP) network. The monitoring station 20 may provide a visible or audible interface to inform the related persons.
Input pins P1, P2, P3 of the three-phase power monitor 21 are respectively connected to the phase power lines L1, L2, and L3 of the three-phase power supply 10 through the third circuit breaker QF3 and the second circuit breaker QF2.
The power supply controller 22 includes an AC-to-DC converter 221 and a second notification device 222. The input terminal of the AC-to-DC converter 221 is connected to one of the phase power lines L1, L2, and L3 of the three-phase power supply 10. For example, the input terminal of the AC-to-DC converter 221 is connected to the phase power line L3 of the three-phase power supply 10. The AC-to-DC converter 221 receives a phase AC voltage from the three-phase power supply 10 and converts the phase AC voltage into a DC voltage.
A cathode output terminal of the AC-to-DC converter 221 is connected to a first normally open contact C1 of the three-phase power monitor 21. An anode output terminal of the AC-to-DC converter 221 is connected to an anode input terminal of the second notification device 222. A cathode input terminal of the second notification device 222 is connected to a second normally open contact C2 of the three-phase power monitor 21.
The first normally open contact C1 is disconnected from the second normally open contact C2 under normal circumstances, that means, for most of the time, the AC-to-DC converter 221 does not provide the DC voltage to the second notification device 222.
When the three-phase power monitor 21 detects an error in the three phase voltages provided by the three-phase power supply 10, the three-phase power monitor 21 connects the first normally open contact C1 to the second normally open contact C2. Then the AC-to-DC converter 221 provides the DC voltage to the second notification device 222. The second notification device 222 is powered to make a public announcement to inform the proximate persons of the need to take action, for example, to cut off the three-phase power supply 10. In one embodiment, the second notification device 222 may include a strobe light which flashes light when the second notification device 222 receives the voltage signal from the three-phase power monitor 21. In some other embodiments, the second notification device 222 may include a speaker which sounds alarms when the second notification device 222 receives the voltage signal from the three-phase power monitor 21.
The power supply controller 20 further includes an opening solenoid KA1. An output terminal of the opening solenoid KA1 is connected to the control terminal of the first circuit breaker QF1. An anode input terminal of the opening solenoid KA1 is connected to the anode output terminal of the AC-to-DC converter 221. A cathode input terminal of the opening solenoid KA1 is connected to the second normally opening contact C2 of the three-phase power monitor 21. The opening solenoid KA1 and the second notification device 222 are connected to the AC-to-DC converter 221 in parallel.
When the three-phase power monitor 21 detects an error in the three phase voltages provided by the three-phase power supply 10, the three-phase power monitor 21 connects the first normally open contact C1 to the second normally open contact C2. Then the AC-to-DC converter 221 provides the DC voltage to the opening solenoid KA1. The opening solenoid KA1 outputs a control signal to the first circuit breaker QF1. The first circuit breaker QF1 disconnects the load 30 from the three-phase power supply 10 in response to receiving the control signal from the opening solenoid KA1.
In step S301, the three-phase power monitor 21 monitors the three phase voltages provided by the three-phase power supply 10.
In step 302, if the three-phase power monitor 21 detects an error in the three phase voltages provided by the three-phase power supply 10, the flow proceeds to step S303. Otherwise, the flow proceeds to step S301.
In step 303, the three-phase power monitor 21 transmits a voltage signal to the power supply controller 22 and the first notification device 23.
In step 304, the power supply controller 22 controls the first circuit breaker QF1 to disconnect the load 30 from the three-phase power supply 10.
In step 305, the first notification device 23 makes a public announcement to inform the proximate persons of the need to take action, for example, to cut off the three-phase power supply 10.
In step 306, when the first notification device 23 receives a voltage signal from the three-phase power monitor 21, the first notification device 23 transmits an alarm signal to the remotely located monitoring station 20 via an IP network.
Although numerous characteristics and advantages have been set forth in the foregoing description of embodiments, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in the matters of arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
In particular, depending on the embodiment, certain steps or methods described may be removed, others may be added, and the sequence of steps may be altered. The description and the claims drawn for or in relation to a method may give some indication in reference to certain steps. However, any indication given is only to be viewed for identification purposes, and is not necessarily a suggestion as to an order for the steps.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012105893649 | Dec 2012 | CN | national |
