JPS588676B2 - Seigiyosouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a non-commutator motor, and more particularly, to a control device for a self-limiting non-commutator motor that is driven using AC as a power source and is capable of regenerative control.

When performing regenerative braking and reversible operation in a self-controlled non-commutator motor, the reference speed command and the feedback signal of the finger speed generator are compared to detect the direction of the torque required for the motor, and the operating order of the thyristor commutator is determined. I'm trying to switch it up.

This operation order switching command is called a torque direction command, and is determined by determining the rotational direction and rotational speed of the motor, and the magnitude (rotation speed command) and polarity (rotation direction command) of the reference speed command. can get.

Conventionally, a direct current finger speed generator has been used as a means for detecting the rotational direction and rotational speed of an electric motor.

The reason is that the rotation direction is determined by the polarity of the finger speed generator.
This is because the rotation speed can be detected by the magnitude of the generated voltage.

However, although DC motors are finger speed generators, they require brushes and a commutator, which is not desirable in commutatorless motors that aim to be completely maintenance-free.

This invention attempts to obtain a speed control signal and a control torque direction command for a commutatorless motor using an AC finger speed generator that does not have brushes or a commutator.

First, a conventional control device for a commutatorless motor will be explained with reference to FIG.

Figure 1 shows the connection diagram. 1 is a reference speed command setting device (hereinafter referred to as speed setting device), and the command value R and the rotational speed of the motor are in a proportional relationship, and when the command value R is positive, If it is negative, it will generate a forward rotation command, and if it is negative, it will generate a reverse rotation command.

Reference numeral 3 denotes a direct current finger speed generator directly connected to the electric motor, and when the electric motor rotates in the normal direction, the output of the finger speed generator, that is, the speed feedback signal F has negative polarity.

This signal F is applied to addition point 2, that is, comparator 2.

In addition, in the case of reversal, a signal of positive polarity is added to addition point 2.

The signal added at addition point 2 has the following four forms.

That is, [1] R is positive and F is negative, and if |R|>|F|, it is positive [2] R is positive and F is negative, and if |R|<|F|, it is negative [31 If it is negative and F is positive and |R|>|F| then it is negative [4] If R is negative and F is positive and |R|<|F| then it is positive The rotational states of the non-commutator motor are shown below: |R|>|F| means power running, |R|<|F| means regenerative braking, so [1] is normal power running, [2] is forward rotation regenerative braking, [3] is reverse rotation powering, and [4] is reverse rotation regenerative braking.

Therefore, [1] and [4] require control torque direction commands in the positive direction, and [gradient] and [3] require control torque direction commands in the opposite direction.

This control torque direction command T is obtained by branching the signal after the addition from a branch point 4 and passing it through a polarity discriminator 5. If the polarity of the branch point 4 is positive, the control torque direction command T is determined to be positive or negative. If so, indicate the negative direction.

The other signal V at the branch point 4 becomes a rotational speed control signal for the commutatorless motor.

In this way, conventionally, the change in the polarity of the direct current finger speed generator 3 has been used as a determining factor for the control torque direction command.

Next, a control device for a commutatorless motor according to the present invention shown in FIG. 2 will be explained.

FIG. 2 is a connection diagram of one embodiment of the present invention, where 1 is a speed setting device similar to the conventional one, and R is its command value.

6 is an absolute value amplifier, 7 is a first polarity discriminator, and 8 is a second polarity discriminator. Their respective outputs Tr and Tv pass through a calculator 9 and become a control torque direction command T.

11 is an AC finger speed generator directly connected to the rotor of the non-commutator motor; 10 is a rectifier which rectifies the AC generated by the finger speed generator 11 and adds it to the addition point 2, that is, the comparator 2;

In this case, the polarity of the speed feedback signal F is always negative or zero regardless of the rotational direction of the finger speed generator 11.

(Zero is when the motor is stopped).

Next, the operation will be explained.

For example, if the setting value 1 is set so that the speed command value R is positive for the purpose of forward rotation of the electric motor, the output Tr of the first polarity discriminator 7 will be ON (hereinafter displayed as 1), and the arithmetic unit Join 9.

On the other hand, the speed command value R is passed through the absolute value amplifier 6 to the feedback signal F.
and added to the additional point 2.

At the addition point 2, the output of the absolute value amplifier 6 is always positive and the feedback signal F is always negative, so the connection point 4 becomes positive or negative depending on the magnitude of each absolute value.

If |R|>|F|, the connection point 4 becomes positive, and the ON signal 1 appears at the output Tv of the second polarity discriminator 8, which is applied to the arithmetic unit 9.

As shown in FIG. 3, the operation of the arithmetic unit 9 is such that the output turns ON only when both the Tr and Tv signals match.

That is, if Tr1 and Tv are 1, the output of the arithmetic unit 9 will be 1.

If the output T of the calculator 9 is defined as 1 as a forward control torque direction command and 0 as a reverse control torque direction command, the following four operation modes are obtained.

(11) When R is positive, Tr is 1, and Tv is 1 when |R|>|F|
and T is 1 (12) R is positive and Tr is 1, |R|<|F| and Tv is 0
and T is 0 [13: |R is negative and Tr is 0, |R|>|F| and Tv is 1 and T is 0 (14) R is negative and T, is 0, |R|<| Tv is O at F｜
and T is 1. That is, [11] and [14] are the forward crawling torque commands, and [12) and [13] are the boat reverse direction control torque direction commands.

Furthermore, these four operation modes correspond to the conventional four operation modes [1], [2], [3], and (4) described above.
1] is normal rotation power running, [12] is normal rotation regenerative braking, [13] is reverse rotation power running, and [14] is reverse rotation regenerative braking.

Therefore, similar results can be obtained as in the conventional method using a direct current finger speed generator.

As described above, according to the present invention, a speed control signal and a control torque direction command for a non-commutated motor can be obtained using an easy-to-maintain AC finger speed generator without using a DC finger speed generator.

Next, FIG. 4, which shows a connection diagram of a commutatorless motor device to which FIG. 2 of the present invention is actually applied, will be explained.

The part A is according to the present invention and is the same as that in FIG.

As described above, the speed control signal V and the control torque direction command T are obtained from the speed command R set by the setting device 1 and the feedback signal F of the AC finger speed generator 11 coupled to the electric motor 12.

The speed control signal V is sent to the speed control amplifier 24 and the current addition point 23
, a current control amplifier 21, and a gate amplifier 19 to control the thyristor converter 16 to adjust the voltage applied to the motor 12.

18 is an AC power supply, 17 is a current transformer, and 15 is a DC reactor.

On the other hand, the control torque direction command T converts the rotor position signal generated by the position detector 13 coupled to the motor rotor to the switching point 22.
By changing the operation order of the thyristor commutator 14, reversible operation and regenerative braking of the electric motor can be performed.

20 is a gate amplifier.

Note that the switching point 22 may be a non-contact type or a contact type.

[Brief explanation of drawings]

Fig. 1 is a connection diagram of a conventional control device for a non-commutated motor, Fig. 2 is a connection diagram showing an embodiment of the control device for a non-commutated motor of the present invention, and Fig. 3 is an explanatory diagram of the operation of a computing unit. , FIG. 4 is a connection diagram showing a commutatorless motor device to which the control device of FIG. 2 of the present invention is applied. In the figure, 1 is a reference speed command setting value, 2 is a comparator, 7,
8 is a polarity discriminator, 9 is a retractor, and 11 is an AC finger speed generator. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A reference speed command setter, where the absolute value of the command value gives the rotational speed command of the non-commutated motor and the polarity of the command value gives the rotational direction command. Determine the polarity of the command value of this reference speed command setter. A first polarity discriminator that compares the absolute value of the command value of the AC finger speed generator connected to the electric motor, and the reference speed command setter with the absolute value of the voltage generated by the AC finger speed generator; a comparator for obtaining a difference signal of the motor and a speed control signal for the motor; a second comparator for determining the polarity of the difference signal of the comparator;
A control device for a non-commutated motor, comprising: a polarity discriminator; and an arithmetic unit that obtains a control torque direction command for the motor from the outputs of the first and second polarity discriminators.