JPS63178785A - Driving gear for pole change motor - Google Patents

Abstract

PURPOSE:To compose a device at a low cost, by using a connector for a connecting section between a stator winding and a power source, to convert the number of poles, and by switching a circuit to a motor protector according to the number of the respective poles based on the detecting signal of the fitted or removed state of the connector. CONSTITUTION:A connector 10 set at the tip of a power-supply cable 16 is fitted on or removed from a low-speed side stationary-terminal 11 connected to the lead wires 1a-1c of a motor winding 1 and a high-speed side stationary- terminal 12 connected to lead wires 1d-1f. By a cable fitting plate (bearing plate)17, the external pipe of the power-supply cable 16 is retained, and the plate 17 comes in contact with the projection 18 of the fitting plate 17 and is provided with low-speed side and high-speed side limit switches 19-20 detecting the connection(the fitted or removed state of the connector 10) of the cable 16, and the cross board 23 of a main circuit casting contactor 24 and the like. As a result, the connector 10 is easily fitted on or removed from, and the connection of the stator winding 1 to a power source is changed (the conversion of the number of poles) in a short time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a drive device for a pole number conversion motor that changes the number of poles of a stator by changing the connection state between a single stator winding and a power supply. It is related to.

[Conventional technology]

Figure 5 shows, for example, Mitsubishi Electric Technical Report 1979 Vo153°A.
8 is a circuit diagram showing the circuit configuration of the conventional pole number changing motor shown in FIG. So-called single winding pole change motors (for example, Con5equent Pol tPAM (Pole tPAM))
Amplitude Modulation) is an example of a typical square torque control circuit (high speed side double Y connection, low speed side Y connection).

In the figure, 1 is a motor winding, 2 is a terminal box attached to the motor, and 3 is a low-speed side terminal provided inside the terminal box 2. This low-speed side terminal 3 is connected to the lead wires 13 to 1c of the motor winding 1. It is connected. 4 is a high-speed side terminal provided in the terminal box 2, and this high-speed side terminal 4 is connected to the lead wire 1d of the motor winding 1.
~1f. 5 houses a low-speed side main circuit closing contactor (or breaker) 6, a high-speed side main circuit closing contactor (or breaker) 7, a low-speed side short-circuit contactor (or breaker) 8, and an overcurrent relay 9. It is a switching board.

Next, the operation will be explained. During low-speed operation, if you turn off the high-speed main circuit closing contactor 7 and the high-speed side shorting contactor 8, the Y connection will not be established, and if you close the low-speed side main circuit closing contactor 6, the number of poles on the low speed side will change. The electric motor is started and operated.

During high-speed operation, if the low-speed main circuit closing contactor 6 is turned OFF and the high-speed side shorting contactor 8 is turned ON, a double Y connection is configured. , the motor is started and operated with the number of poles on the high-speed side.

[Problem that the invention seeks to solve]

Since the drive device of the conventional pole change motor is configured as described above, when high voltage and large capacity are achieved, the low speed side main circuit closing contactor and the high speed side main circuit closing contactor must be used as circuit breakers. For this reason, the switching panel provided in the central electrical room becomes large and occupies a large space, and it also has disadvantages such as being expensive. Furthermore, since it is necessary to install an additional power cable compared to a single-speed motor, there are problems such as increased construction costs.

This invention was made to solve the above-mentioned problems, and its purpose is to provide a drive device for a pole-changing motor that requires approximately the same device space as a single-speed motor and can be constructed at low cost. shall be.

[Means for solving problems]

A drive device for a motor with pole number conversion according to the present invention converts the number of poles by using a connector at a connection between a stator winding and a power source, and based on a detection signal of a detection means for detecting the attachment/detachment state of the connector. The control circuit is equipped with a control circuit that switches the circuit to the motor protection device corresponding to each number of poles.

[For production]

Since the connector according to the present invention is easy to attach and detach, it is possible to change the connection between the stator winding and the power source, change the tabs, and change the number of poles in a short time and easily. By switching the circuit to the motor protection device corresponding to each number of poles using the detection signal of , it is possible to achieve protection coordination for different protection setting values depending on the number of poles.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a front layout view of the fixed terminal section of the motor during low-speed operation. 10 is a connector provided at the tip of the power cable 16, and this connector 10 is the lead wires 1a to 1c of the motor winding 1. The low speed fixed terminal 11 is connected to the high speed fixed terminal 11 connected to the lead wires 1d to 1f, and the high speed fixed terminal 12 is connected to the lead wires 1d to 1f.

17 is a cable mounting plate (support plate), and the power cable 16
Hold the lead or outer tube. 18 is a protrusion provided on the cable mounting plate 17, and 19 is activated to connect the power cable 16 when the protrusion 18 comes into contact with it! 2, a low-speed limit switch serving as a detection means for detecting the attachment/detachment state of the connector 10; and 27, a lid that closes an entrance/exit 28 for the power cable 16 provided in the terminal mounting box 2;

Fig. 2 is a front layout diagram of the fixed terminal section of the motor during high-speed operation. 15 is a short circuit that shorts the three connectors 10 that are connected to and removed from the low-speed fixed terminal 11, and the short-circuited part is insulated. Covered. 20 is the protrusion 1 of the cable mounting plate 17
8 is a high-speed side limit switch as a detection means that operates when it comes into contact with the power cable 16 to detect the connection of the power cable 16, the tab, and the attachment/detachment state of the connector 10; 23 is the power cable 16;
Main circuit closing contactor (or circuit breaker) 24 connected to
and a switching board housing an overcurrent relay 9.

FIG. 3 shows an example of circuit connection of this embodiment. Corresponding to FIG. 1, lead wires 1a to 1c and 1d to
f is connected to the low-speed side fixed terminal 11 and the high-speed side fixed terminal 12 in the terminal mounting box 2. 21 and 22 are interlock signals issued by limit switches 19 and 20, respectively.

FIG. 4 shows circuit switching between motor protection devices corresponding to the number of poles based on detection signals from the detection means, knob, low-speed limit switch 19, and high-speed limit switch 20 in FIGS. 1 and 2. The limit switches LSI and LS2 are controlled by the interlock signals 21 and 22 issued by the limit switches 19 and 20, respectively, and the limit switches LSI and LS2 are connected to the relays RY1. Connected in series with RY2, these relays RY1 and RY2 are energized and the contacts RY1-
1. When RY2-'2 is closed, thermal relay THR1 and overcurrent relay 0CR1, or T4R2 and 0CR2
One of the series circuits is closed. Note that PBS1 and PBS2 are a start push button switch and a stop push button switch, respectively.

Next, the operation will be explained. 1 and 3 show low-speed operation. During this low-speed operation, the connector 10 attached to the power cable 16 is connected to the low-speed fixed terminal 11.
Connect to. At this time, the protrusion 18 of the cable mounting plate 17
contacts the limit switch 19, actuating the limit switch 19, and emitted from the limit switch 19.

Interlock signal 21 turns limit switch LS1 to O
Let it be N. In this state, start pushbutton switch PBS
If 1 is pressed, the starting pushbutton switch PBS 1-
Stop pushbutton switch PBS2 - Main relay MC -
The circuit of relay contact RY1 - thermal relay THR1 - overcurrent relay 0CR1 is closed, and thermal relay THR1 and overcurrent relay 0CR1, which are in protection coordination with the low-speed motor characteristics, are activated, and the operating state is changed to main relay MC. It is self-maintained by the closed circuit of contact MC-1.

Next, when switching to high-speed operation, the stop pushbutton switch PB82 is pressed to temporarily stop the operation of the electric motor. Then, as shown in FIG. 2, connect the connector 10 attached to the power cable 16 to the high-speed side fixed terminal 12,
The connector 10 attached to the short circuit 15 is connected to the low-speed side fixed terminal 11 to short-circuit the low-speed side fixed terminals. At this time, by using a connector for the terminal part, the labor of removing and installing insulating taping can be omitted, so the work time for connecting scrap wire can be reduced by almost half compared to the conventional bolt tightening and insulating taping method. .

In this way, the power cable 16 and the short circuit 15 are connected to the high-speed side fixed terminal 12. When connected to the low-speed side fixed terminal 11 (indicated by the two-dot chain line in FIG. 3), the protrusion 18 of the cable mounting plate 1T contacts the limit switch 20 and activates the limit switch, causing the limit switch 20 to emit a signal. The limit switch L is activated by the ink lock signal 22.
Turn on S2. If the starting pushbutton switch PB81 is pressed again in this state, the starting pushbutton switch P
BS1 - Stop pushbutton switch PBS2 - Main relay MC - Relay contact RY2 - Thermal relay THR2 - Overcurrent relay 0 The circuit of CR1 is closed, and the thermal relay THR2 and overcurrent are in protection coordination with the high-speed motor characteristics. Relay 0CR2 is activated, and this operating state is the contact MC-
It is self-maintained with one closed circuit.

In addition, in the above embodiment, connection switching of square torque (double Y
Although an example of connection (wire connection/Y connection) has been shown, the same applies to connection switching for constant torque control (double Y connection/Δ connection) and connection switching for constant output control (Δ connection/double Y connection).

In addition, in the above embodiment, assuming the case of a high voltage electric motor,
Although a single connector 10 is used for each phase, in the case of a low-voltage motor, a three-phase all-in-one type connector may be used.

Further, in the above embodiment, the protrusion of the cable mounting plate is configured to activate the detection device that detects the attachment/detachment state of the connector, but the detection device may be configured so that the connector itself activates the detection device. An auxiliary contact of a connector with an auxiliary contact may be used as the detection means.

〔Effect of the invention〕

As described above, according to the present invention, a connector is employed at the connection between the stator winding and the power source, and the connection/disconnection state of the connector is detected to switch the circuit of the motor protection device corresponding to each extreme. With this configuration, it is possible to connect a single stator winding to a power source in a short time, and a protection circuit suitable for each motor number of poles is secured. Therefore, in the case of a pole change motor used for applications that do not require frequent switching and can allow sufficient time for switching, an expensive switching panel or additional cable for switching is required. This eliminates the need for υ, which has the effect of providing even more economic benefits.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the structure near the fixed terminal section of a pole converter motor according to an embodiment of the present invention when operating at low speed;
Figure 2 is the same diagram as above when operating on the high speed side, Figure 3 is a circuit diagram of the pole number changing motor of the present invention when operating on the low speed side, and Figure 4 is a relay sequence diagram used in the pole number changing motor of the present invention. , FIG. 5 is a circuit diagram of a conventional pole change motor. 1 is a single stator winding (motor winding), 10 is a connector,
19.20 is a detection means (limit switch). In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In a pole number conversion motor that changes the number of poles of a stator by changing the connection state between the single stator winding and the power source, a connector provided at a connection between the single stator winding and the power source; , detection means for detecting the attachment/detachment state of the connector;
A drive device for a motor with variable number of poles, comprising: a control circuit that switches circuits between motor protection devices corresponding to the number of poles based on a detection signal from the detection means.