CN202455255U - Winding switching circuit of elevator dragging switching magnetoresistance motor power converter - Google Patents

Abstract

The elevator pulls the winding switching circuit of the switched reluctance motor power converter, including a DC power supply and a winding unit; the winding unit includes a first winding and a second winding; each winding unit has and only one winding is energized; the first winding One end connected to the second winding is connected to the second switching tube and the negative terminal of the second diode, the other end of the second switching tube is connected to the positive output terminal of the power supply, and the positive terminal of the second diode is connected to the negative output terminal of the power supply ; The other end of the first winding is connected to the positive end of the first diode and the first switch tube, the negative end of the first diode is connected to the positive output end of the power supply, and the other end of the first switch tube is connected to the negative output end of the power supply ; The other end of the second winding is connected to the positive end of the third diode and the third switch tube, the negative end of the third diode is connected to the positive output end of the power supply, and the other end of the third switch tube is connected to the negative output end of the power supply . The utility model has the advantages of simple structure and less required switching tubes.

Description

Winding switch circuit of power converter of switched reluctance motor for elevator pull

technical field

The utility model relates to a winding switch circuit of a power converter of a switched reluctance motor for an elevator pull reference.

Background technique

The existing two most commonly used four-phase winding switched reluctance motor power converter main circuit structure forms, or when the switching tube is turned off, the voltage is relatively high and the voltage of the armature winding is small, which cannot fully use the power supply capacity and the electric torque The effectiveness is also low, as shown in Figure 1, the main circuit of the bipolar power converter. Only one main switch for each phase is its main advantage, but the voltage rating of the main switch and freewheeling diode is U _S + ΔU (ΔU is any transient voltage caused by commutation), and the voltage applied to the winding is only U _S /2, failed to fully use the rated voltage of the switching device and the capacity of the power supply. In addition, in the main circuit of the power converter with this structure, when the motor operates in single phase, because only one switch is turned on instantaneously, C ₁ and C ₂ fluctuate alternately. This problem can be solved by adopting the two-phase operation mode (the premise is that the upper and lower parts of the circuit have one phase winding conducting at the same time), but in the two-phase operation, the effectiveness of the electric torque will be reduced, and the resistance of the current in the phase winding However, the loss will increase; moreover, if the two phases are energized at the same time, the magnetic circuit of the motor will be saturated, which will further reduce the effectiveness of the current to generate electric torque.

Either the number of switching tubes required is large, and the economy is poor, such as the asymmetrical half-bridge main circuit shown in FIG. 2 . Its characteristics are: (1) The voltage rating of each main switching tube is U _S , which is approximately equal to the voltage rating of the motor winding, so this line uses up the rated voltage of the main switching tube, and the effective full power supply voltage can be used Control phase winding current. (2) Since each phase winding is connected to its own asymmetrical half-bridge, the current control between phases is completely independent in the circuit. (3) Three kinds of voltage circuits can be provided for the phase windings, that is, the positive voltage circuit when the upper and lower main switches are turned on at the same time, the zero voltage circuit when one main switch is kept on and the other main switch is turned off, and the upper and lower main switches are turned off. , The negative voltage circuit when the lower main switch is turned off. In this way, the energy non-feedback chopping method can be used in the low-speed chopping control mode, that is, during the chopping freewheeling period, the phase current continues to flow in the "zero voltage loop", avoiding the reactive energy exchange between the motor and the power supply , which is beneficial to increase the torque, improve the utilization rate of the power converter capacity, reduce the chopping times, control the fluctuation of the power supply voltage, and reduce the torque ripple. (4) Two main switches are required for each phase, which fails to fully reflect the inherent advantages of the unipolar switched reluctance motor power converter over other AC speed control system converters. From the above analysis, it can be seen that the asymmetrical half-bridge type has great advantages over the bipolar power supply type in terms of performance. The only disadvantage is that the number of switching devices used is large, especially for non-small SR motors. The cost of the power converter is poor in economy.

Utility model content

In order to overcome the above-mentioned shortcomings of the prior art, the utility model provides a switch reluctance motor with a simple structure, a small number of switch tubes, and any conductive winding can receive the full voltage when power is applied. Winding switching circuit of a power converter.

The winding switching circuit of the switched reluctance motor power converter used in the elevator pull includes an externally input DC power supply and two winding units connected in parallel. The DC power supply is loaded on the two winding units; the winding unit includes the first winding connected in series and Second winding; one and only one winding in each winding unit is energized;

One end of the first winding connected to the second winding is connected to the second switching tube and the negative end of the second diode, the other end of the second switching tube is connected to the positive output terminal of the power supply, and the positive end of the second diode is connected to the power supply The negative output end of the first winding; the other end of the first winding is connected to the positive end of the first diode and the first switch tube, the negative end of the first diode is connected to the positive output end of the power supply, and the other end of the first switch tube is connected to the power supply The negative output end of the second winding; the other end of the second winding is connected to the positive end of the third diode and the third switch tube, the negative end of the third diode is connected to the positive output end of the power supply, and the other end of the third switch tube is connected to the power supply negative output terminal. After the winding is powered off, because the winding is an inductive load, the winding current cannot drop to zero immediately, and the unidirectional conductivity of the diode is used to feed back part of the electric energy to the power supply.

Further, the windings of the two winding units are combined in accordance with the principle of multiplication to form a four-segment cycle in which two twos are conducted. Specifically: the first winding of the first winding unit is turned on and the first winding of the second winding unit is turned on -> the first winding of the second winding unit is turned on and the second winding of the first winding unit is turned on -> the first winding The second winding of the unit is turned on and the second winding of the unit is turned on—>the second winding of the unit is turned on and the first winding of the first winding unit is turned on.

The technical idea of the utility model is: to make the windings in series in two groups evenly distributed in two groups of switching circuits, each winding unit has three switching tubes, and the second switching tube of each winding unit is shared, saving the number of switching tubes, After electrification, the windings that are turned on can receive the full voltage, and the efficiency is high.

The utility model has the advantages of simple structure, less required switch tubes, and any conducting winding can receive full voltage when power is applied.

Description of drawings

Fig. 1 is the main circuit of the conventional bipolar power supply type four-phase switched reluctance motor power converter.

Fig. 2 is the main circuit of the conventional asymmetrical half-bridge four-phase switched reluctance motor power converter.

Fig. 3 is a circuit diagram of the utility model.

Detailed ways

With reference to Fig. 3, further illustrate the utility model:

The winding switching circuit of the power converter of the switched reluctance motor used in the elevator pull includes an externally input DC power supply Us and two winding units connected in parallel. The DC power supply Us is loaded on the two winding units; the winding unit includes the first winding unit connected in series A winding and a second winding; each winding unit has and only one winding is energized;

One end of the first winding connected to the second winding is connected to the second switching tube and the negative end of the second diode, the other end of the second switching tube is connected to the positive output terminal of the power supply, and the positive end of the second diode is connected to the power supply The negative output end of the first winding; the other end of the first winding is connected to the positive end of the first diode and the first switch tube, the negative end of the first diode is connected to the positive output end of the power supply, and the other end of the first switch tube is connected to the power supply The negative output end of the second winding; the other end of the second winding is connected to the positive end of the third diode and the third switch tube, the negative end of the third diode is connected to the positive output end of the power supply, and the other end of the third switch tube is connected to the power supply negative output terminal. After the winding is powered off, because the winding is an inductive load, the winding current cannot drop to zero immediately, and the unidirectional conductivity of the diode is used to feed back part of the electric energy to the power supply.

Specifically as shown in Figure 3, the first winding unit includes a motor winding A, an electronic winding C, diodes D1, D2, D3 and switching tubes T1, T2, T3;

The second winding unit includes electronic winding B, electronic winding D, diodes D4, D5, D6 and switch tubes T4, T5, T6.

Among them, D1 and T1 are connected in series, the cathode of D1 is connected to the positive terminal of the power supply Us, the cathode of T1 is connected to the negative terminal of the power supply Us; T2 and D2 are connected in series, the anode of T2 is connected to the positive terminal of the power supply Us, and the anode of D2 is connected to the negative terminal of the power supply Us; D3 and T3 In series, the cathode of D3 is connected to the positive terminal of the power supply Us, the cathode of T3 is connected to the negative terminal of the power supply Us; D4 and T4 are connected in series, the cathode of D4 is connected to the positive terminal of the power supply Us, the cathode of T4 is connected to the negative terminal of the power supply Us; T5 and D5 are connected in series, and the anode of T5 Connect to the positive terminal of the power supply Us, the anode of D5 is connected to the negative terminal of the power supply Us; D6 and T6 are connected in series, the cathode of D6 is connected to the positive terminal of the power supply Us, and the cathode of T6 is connected to the negative terminal of the power supply Us; the A and C phase windings are connected in series, and the two ends are respectively across Connected at the connection point of D1 and T1, D3 and T3, where the series connection point of A and C coincides with the series connection point of T2 and D2; the B and D phase windings are connected in series, and the two ends are respectively connected to the connection point of D4 and T4 , D6 and T6 connection points, where B, D series connection points coincide with T5, D5 series connection points.

The windings of the two winding units are combined in accordance with the principle of multiplication to form a four-segment loop running sequence in which two twos are conducted. Specifically: the first winding of the first winding unit is turned on and the first winding of the second winding unit is turned on -> the first winding of the second winding unit is turned on and the second winding of the first winding unit is turned on -> the first winding The second winding of the unit is turned on and the second winding of the unit is turned on—>the second winding of the unit is turned on and the first winding of the first winding unit is turned on. Combined with Figure 3, the four-phase windings of the motor are divided into four sections according to the sequence of AB—BC—CD—DA. As the rotor moves, the A-phase winding needs to be powered off and the BC two-phase winding is turned on, then the T1 switch tube is turned off, the T3 switch tube is closed, and so on. The next step is the CD phase, the switch tube T4 is turned off and T6 is closed until the transformation Four times a cycle, so repeated, the motor runs.

The technical concept of the utility model is: to make the windings in series in two groups evenly distributed in two groups of switching circuits, each winding unit has three switching tubes, and the second switching tube of each winding unit is shared, saving the number of switching tubes, After electrification, the windings that are turned on can receive the full voltage, and the efficiency is high.

The utility model has the advantages of simple structure, less required switch tubes, and any conducting winding can receive full voltage when power is applied.

The content described in the embodiments of this specification is only an enumeration of the realization forms of the utility model concept, and the protection scope of the utility model should not be regarded as being limited to the specific forms stated in the embodiments, and the protection scope of the utility model also extends to Equivalent technical means that those skilled in the art can think of according to the concept of the utility model.

Claims (3)

1. elevator is dragged the winding switching circuit of quoting the switched reluctance motor power inverter, it is characterized in that: comprise the DC power supply of outside input and two winding elements that are connected in parallel, DC power supply loads on two winding elements; Winding element comprises first winding and second winding that is connected in series; There is and only has a winding energising in each winding element;

An end that links to each other with second winding of first winding is connected the negative terminal of the second switch pipe and second diode, and the other end of second switch pipe connects the positive output end of power supply, and the anode of second diode connects the negative output terminal of power supply; The other end of first winding connects the anode and first switching tube of first diode, and the negative terminal of first diode connects the positive output end of power supply, and the other end of first switching tube connects the negative output terminal of power supply; The other end of second winding connects the anode and the 3rd switching tube of the 3rd diode, and the negative terminal of the 3rd diode connects the positive output end of power supply, and the other end of the 3rd switching tube connects the negative output terminal of power supply.

2. As claimed in claim 1Elevator is dragged the winding switching circuit of quoting the switched reluctance motor power inverter, it is characterized in that: the winding of two winding elements forms the operation order of four sections conductings in twos that circulate according to multiplicative principle with combining form.

3. As claimed in claim 2Elevator is dragged the winding switching circuit of quoting the switched reluctance motor power inverter, it is characterized in that: first winding conducting of first winding element and second winding element, the first winding conducting —>First winding conducting of second winding element and first winding element, the second winding conducting —>Second winding conducting of first winding element and second winding element, the second winding conducting —>Second winding conducting of second winding element and the first winding conducting of first winding element.