CN87200720U - Phase sequence monitor of three-phase supply - Google Patents

Abstract

The utility model discloses a phase sequence monitor of a three-phase power supply, which is composed of a sampling line, a signal driving line, photocouplers, and a displaying power supply. When a three-phase power supply and a zero line are connected in, sampling is carried out at a phase A and a phase C, and a phase B provides a power supply. The photocouplers are used as sensing, driving and isolating elements. When phase error and phase lack of the three-phase power supply occur, a control signal is immediately sent out to cut off an input three-phase power supply and protect electric equipment.

Description

Phase sequence monitor of three-phase supply

The utility model belongs to the three-phase ac power supply monitoring technical field, particularly the three-phase power supply phase sequence monitor.

The equipment of the three-phase ac power supply power supply of in communication and other industrial sector, using, as communicate by letter and use silicon rectifier, AC distribution panel, no-break power unit (UPS) and exchange threephase motor power supply etc., phase sequence to three-phase ac power supply has strict requirement, if generation misphase and phase shortage will cause equipment breakdown.Disclosed CN85204103U instructions, the test pencil for measuring phase-sequence of being put down in writing, can only do simple and easy phase sequence test, the CN85203166U instructions is and for example disclosed, the wideband three-phase electricity phase-sequence meter of being put down in writing, complex structure, select for use expensive electron device to form, also need special-purpose stabilized voltage supply or powered battery, so the cost height.Above-mentioned two examples all no signal drive function, are unsuitable for the long-term operation continuously of place in circuit; And with the phase sequence that three test probes are tested three-phase supply, bimanualness inconvenience, thereby widespread use is restricted.

The purpose of this utility model provides a kind of no step-down transformer, need not to be equipped with in addition direct supply, simple in structure, volume is little, low in energy consumption, can move continuously by place in circuit; and make the three-phase power supply phase sequence monitor that signal drives function that has simple, with low cost; the phase sequence of continuous monitoring three-phase supply in the incoming transport circuit; when misphase, phase shortage and power failure take place when; control signal can take place immediately, cuts off AC power protection consumer.

The utility model is made up of sampling circuit, signal driver circuit, photoelectric coupling circuit and display power supply, sees accompanying drawing.Sample line route silicon triode BG ₁, capacitor C ₁, diode D ₁, stabilivolt DW ₁And resistance R ₁, R ₂, R ₃, R ₄Form, take a sample mutually at A, C.The signal driver circuit is by silicon triode BG ₂, capacitor C ₂, C ₃, C ₄, diode D ₂, stabilivolt DW ₂, LED ₁, LED ₂, silicon rectification bridge QL and resistance R ₄, R ₅, R ₆, R ₇, R ₈, R ₉And the relay J composition, provide signal to drive and the signal display power supply mutually by B.By sensing and driving element photoelectric coupling circuit GD two parts are isolated.Its monitoring function is achieved in that by figure and inserts A, B, C three-phase and O line that when the correct and intact phase time of phase sequence, A is through D ₁Half-wave rectification, R ₄BG is provided after the current limliting ₁Base current, C is through C ₁Pass through R after step-down, the phase shift ₂, DW ₁BG is provided ₁The collector forward bias, A is 240 ° mutually because C lags behind mutually, and C is mutually also through C ₁Phase shift increases drag angle, and making always has certain hour A and C phase voltage direction to make BG in the same way in every half period ₁Conducting; BG ₁The light emitting diode of photoelectric coupling circuit is connected luminously after the conducting, and B is through C ₄Step-down, QL bridge rectifier and C ₃, DW ₂Filtering voltage regulation provides the operating voltage of the silicon phototriode of photoelectric coupling circuit, and when in the photoelectric coupling circuit during lumination of light emitting diode, the silicon phototriode is with regard to conducting, and the forward voltage of introducing after its conducting is through C ₂, R ₆Filter more level and smooth DC voltage through R ₆, R ₇Add to BG after the dividing potential drop ₂Base stage, make BG ₂Saturation conduction.BG ₂After the conducting, LED ₁Connect luminous, signal relay J adhesive and send the normal opened contact adhesive of J, drive the auxiliary reclay action, make contactor connect three-phase supply, consumer normal operation input.

If the generation misphase is established C and put upside down mutually with B mutually, A is 120 ° mutually because B lags behind mutually, and B is similar through C ₁Phase shift, drag angle increases, and is increased to about when being 180 °, and A is suitable for opposite, so BG with B voltage direction mutually mutually in every half period ₁By (be in and owe conducting state), photoelectric coupling circuit does not have drive current, and the silicon phototriode can not conducting, BG ₂No base current and end LED ₁Obstructed, the J contact discharges, and normal opened contact disconnects, and the auxiliary reclay contact disconnects, and contactor cuts off AC power, and consumer is protected.

If the generation phase shortage lacks A mutually or lack B mutually or the C phase, BG no matter be ₁And BG ₂All conductings simultaneously.BG ₁And BG ₂Conducting simultaneously then signal driver circuit will be sent control signal cut-out AC power.For example lack B phase, BG ₁Though the energy conducting, BG ₂No operating voltage and ending, the contact of signal relay J must discharge, and auxiliary reclay and contactor contact disconnect and cut off AC power, and consumer is protected.

The utility model is described in further detail below with reference to accompanying drawing, BG in the accompanying drawing ₁, BG ₂Be silicon triode, C ₁～C ₄Be electric capacity, D ₁, D ₂Be diode, DW ₁, DW ₂For voltage stabilizing diode, GD are that photoelectric coupling circuit, J are signal relay, LED ₁, LED ₂For light emitting diode, QL are silicon rectification bridge, R ₁～R ₉Be resistance.Above-mentioned three-phase power supply phase sequence observation circuit is simple, the application components and parts are few, volume is little, need not step-down transformer or be equipped with direct supply, low in energy consumption in addition, can directly insert or make plug-in unit incoming transport circuit moves continuously, and make simply, with low cost, be particularly suitable for using in the communication power supply equipment that exchanges 50HZ or 60HZ three-phase 380V power supply and other similar AC distribution equipment phase sequence monitoring means as three-phase supply.

Claims (2)

1, the three-phase power supply phase sequence monitor is made up of sampling circuit, signal driver circuit, photoelectric coupling circuit and display power supply.It is characterized in that: sample line route BG ₁, C ₁, D ₁, DW ₁And R ₁, R ₂, R ₃, R ₄Form, take a sample mutually at A, C.The signal driver circuit is by BG ₂, C ₂, C ₃, C ₄, D ₂, DW ₂, LED ₁, LED ₂, QL and R ₄, R ₅, R ₆, R ₇, R ₈, R ₉And signal relay J composition, provide signal to drive and the signal display power supply mutually by B.The sample line route is undertaken the GD and the signal driver circuit BG of sensing, driving and buffer action ₂Base stage link to each other.

2, three-phase power supply phase sequence monitor according to claim 1 is characterized in that described sampling circuit and signal driver circuit isolate with a photoelectric coupling circuit.