JPS60156296A - Commutation compensator of dc machine - Google Patents

Abstract

PURPOSE:To normally compensate the commutation at normal/reverse operating time by providing a detecting brush for detecting a voltage between brush commutator segments near the exit of the brush, and controlling the current amount of an auxiliary winding in response to the detected voltage of the positive or negative brush of the brushes. CONSTITUTION:Positive and negative brushes 13A, 13B for detecting the voltage between brush commutator segments are provided near the outlet of a brush 11, and the detected voltages of the positive and negative brushes 13A, 13B are applied to function generators 16A, 16B. A rotating direction discriminator 19 inputs a signal from a rotating speed detector 18 and applies rotating direction signals (a), (b) to a power amplifier 10 and switches 17A, 17B. A power converter 20 controls the current of an auxiliary winding 10 in response to the outputs of function generators 16A, 16B by the switches 17A, 17B and rotating direction signals (a), (b).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a DC machine, and particularly to a rectification compensation device for a DC machine that can improve rectification performance.

[Background of the invention]

DC machines have a phenomenon in which the sparkless band shifts with respect to the rotational speed, making it difficult to achieve sparkless commutation over the entire operating range. As a countermeasure against this problem, a method has been proposed in which the rectification state is detected, the interpolation magnetomotive force is adjusted according to the rectification state, and sparkless rectification r is achieved. An embodiment thereof is shown in FIGS. 1 to 3. 1st
The figure shows the main parts of a DC machine, and a main pole 2 and a complementary pole 3 are provided on the inner periphery of the yoke l. Main pole 2It is formed by the field core 4 and the field winding 5, and has no role of providing main magnetic flux to the armature winding 6 of the armature 9 rotating inside the stator.
is formed from a commutator core 7 and a commutator winding 8, and serves to provide a commutator magnetic flux to generate a rectified electromotive force during a rectification phenomenon in which the current flowing in the armature winding 6 is reversed. do.

In addition, an assistant ffJJ provided on the tip side of the commutating pole iron core 7
xO acts differentially with the commutator winding 8, and as shown in Fig. 2, as the no-spark zone moves toward the overflow side as the rotational speed increases, its magnetomotive force is adjusted. Is it responsible for moving the load shaft onto the O-P line at the center of the non-sparking zone? do.

Figure 3 is a circuit block diagram of a rectification compensator that supplies current to the auxiliary winding according to the rectification state using an external power supply. show. In FIG. 3, 11 is a brush, 12 is a commutator, 13 is a detection brush, and 14 is a power amplifier. With this configuration, the armature current IM is brush 11*! It flows to the armature winding via the Ml & child 12, and further flows from the brush 11 to the commutator winding 8. The voltage between the brush commutator pieces (hereinafter referred to as
A detection brush 13 detects the voltage Vbk (abbreviated as a detection voltage), and a power amplifier 14 supplies the voltage in accordance with the detection voltage Vb. That is, in this method, if the detection voltage Vb is within 137 of the normal spark generation limit voltage, the brush will not generate any sparks, so the current i is applied to the auxiliary winding lO according to the detection voltage Vb.
c? Flowing interpolation magnetomotive force? The purpose is to adjust the detection voltage Vb' to always keep it within 137 to achieve sparkless rectification.

However, although this method is good for one-way rotation, when applied to a DC machine that rotates in forward and reverse directions, the direction of rotation and armature current direction will be reversed depending on the operating condition (in the case of reverse rotation due to armature switching). Correspondingly, the detection voltage Vb is also reversed, resulting in the disadvantage that normal rectification compensation cannot be performed.

[Purpose of the invention]

An object of the present invention is to provide a rectification compensation device for a DC machine that can perform normal rectification compensation even when applied to a machine capable of forward and reverse operation.

[Overview of the invention]

The main point of the present invention is to provide a detection brush for detecting the voltage between the brush commutator pieces (detection voltage) near the entrance and exit of the brush,
In addition, input the detection voltages of the positive brush and negative brush in this book into the positive brush function generator and negative brush function generator, which have different functions, respectively, and select one function generator depending on the rotation direction of the armature. The purpose is to control the amount of current and sound in the auxiliary winding according to the results.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 4 to 7.

FIG. 4 shows a circuit block diagram of a leakage compensator applied to a DC machine operated in forward and reverse directions according to the present invention. In the figure, 13A
(for positive brush), 13B (for negative brush), 13 is detection brush, 15A, 15B is isolation amplifier, 16A, 16
B is a function generator, 17A.

17B is an analog switch, 18 is rotation speed detection 2 diagnosis, 1
Reference numeral 9 denotes a rotation direction determination circuit, and 20 a power amplifier that supplies current to the auxiliary winding 10 and can change the direction of the current.

Figure 5 shows linear rectification and under-rectification ii'i for the book position.
= indicates the brush contact voltage drop during overload flow. Figure 5 (
b) is a positive brush (current flows from the brush to the commutator),
(b) shows the case of a negative brush (the current force flows through the current flow to the duck brush), A shows the case of linear rectification, B shows the under-rectification, and C shows the case of overload flow. From the figure, it can be seen that the rectification condition of a negative flow machine can be determined by detecting the pressure (detected voltage) fc between the brush outlet, that is, between the brush commutator pieces at the rear end of the brush 27, and judging from the magnitude and direction of this voltage. Ru.

Here, in the non-spark band movement phenomenon, the non-spark band moves to the overload flow side as the rotation speed increases, so the detected voltage Vb at the rear end of the brush shifts to the negative side in (a). ,(B)
With a negative brush, the S output voltage at the rear end of the brush is ■.

shifts to the positive side.

FIG. 6 shows the detection voltage Vb by the detection brushes 13A and 13B.
l, V)2 and the output of the function generator VKI, VK2
(') indicates a relationship. FIG. 6(a) shows the input/output relationship of the function generator for the positive brush, and FIG. 6(b) shows the relationship between the input and output of the function generator for the negative brush. In other words, in the positive brush I4A number generator of (a), when the sparkless zone moves to the overload flow 011j, the detected acid ratio vb shifts to the negative side, so the When the detection voltage is Vbl, it is output to a positive voltage Vg, and that voltage V
X+ becomes more functional as the input detection voltage Vbl shifts to the negative side. (I:I) negative brush function generator-5
When the non-sparking car moves to the over-rectification side, the detection voltage Vb2 shifts to the positive side, so when the detection voltage Vb2 is higher than the command ■ (unlike the command ■, the command value Vb2o), the positive voltage Vx
zk is output, and its voltage VK2 becomes functionally larger as the input detection voltage vb2 shifts to the positive side. Here, the slopes of the functions of the function generator for the positive brush and the function generator for the negative brush are different, and the slope of the function generator for the negative brush is different. The 7th one was made smaller.
As shown in the brush VI characteristic in the figure, (current? The horizontal axis shows the brush contact voltage drop v1 of the positive brush and the brush contact voltage drop V2 of the negative brush), even with the same rectification, the brush contact voltage of the positive brush This is because the drop is large (V2>V+).

In FIGS. 4 to 7, in the case of forward rotation (the commutators 1 and 2 rotate in the direction indicated by the solid arrow X, and the armature current 1M is in the direction indicated by the solid arrow), the rotation speed detector 18 The rotation direction determination circuit 19 which receives the output from the output terminal operates and the switch 17A in the path a is turned on, so the detection bluff 13A detects the detected voltage at the rear end of the pusher (the brush that is coming out in one bundle is the positive brush). Vb1 is manually inputted to the positive brush function generator 16A in a state where it is insulated from the main circuit of the DC machine by the insulation amplifier 15A. Including this detection voltage, the non-sparking zone is overloaded @ I
Since it becomes a negative voltage when moving to HQ, it is converted to a positive voltage by the positive brush function generation Mt16A, and compared with Vbl of the command α), a positive voltage VK is determined according to the value of this detected voltage Vb. , is energized to point A via switch l7Ak.

On the other hand, in the case of reverse rotation (the commutator 12 rotates in the direction indicated by the chain arrow X, and the armature current IM is in the direction indicated by the chain line)
In this case, the rotation direction determination circuit 9 operates and the switch 17B of the path 6 is turned on, so the detection voltage Vb2 at the rear end of the brush (the brush being detected is a negative brush) is changed by the detection brush 13B to the insulation amplifier. 15B (r) is input to the negative brush function generator 16B. This detection voltage Vb2 becomes a positive voltage when the sparkless zone moves to the overload flow 11111, so it is commanded by the negative brush function generator 16B. ■v bz.

A positive voltage v according to the value of this detection voltage vb2 compared with
K2 is energized to point A via switch 178.

The current IC of the auxiliary winding IO is supplied to the power amplifier 20, and the direction is determined according to the output of the rotation direction determining circuit 19 (the direction of the arrow shown by the solid line for forward rotation and the chain line for reverse rotation).
The output voltage Vx (or v
The size is adjusted depending on the construction.

In other words, this rectification compensator has a detection voltage V in the case of forward rotation.
The auxiliary winding l is set so that b1 is within the spark generation limit voltage.
The current amount of O jc'Th function generator 16A - is adjusted according to the output voltage VI[+, and in the case of reverse, the detection voltage Vb2
The amount of current in the auxiliary winding lO is adjusted according to the output voltage VK2 of the jck function generator 16B so that the current amount falls within the spark generation limit voltage. Furthermore, the functions of the positive 7° lash function generator 16A and the negative brush function generator 16B are made different, and the brush contact voltage drop v of the positive and negative brushes with respect to rectification is
Since the difference in L is corrected by the slope of the function of both function generators 16A and 16B, even if a no-spark zone movement phenomenon occurs during forward and reverse rotation, the rectification 1c of the auxiliary winding lO is always adjusted according to the rectification state of the brush. By adjusting the size and direction of the DC voltage appropriately, sparkless rectification of the DC machine can be achieved at all times.

〔Effect of the invention〕

According to the present invention, it is possible to provide a rectification compensator for a DC machine that can compensate for the no-spark band movement phenomenon even during forward and reverse rotations, and can always achieve full spark-free rectification.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the stator and rotor of a DC machine, Fig. 2 is an explanatory diagram of the no-spark zone movement phenomenon, Fig. 3 is a circuit block diagram of a conventional rectification compensator, and Fig. 4 is a diagram of the present invention. A circuit block diagram of the rectification compensation device. Figure 5 is a characteristic diagram showing brush contact voltage drops of positive and negative brushes corresponding to linear rectification, under-rectification, and overload flow. Figure 6 is a function generator for positive and negative brushes. FIG. 7 is a characteristic diagram of the current-brush contact voltage drop of the positive and negative brushes. lO... Auxiliary winding, 13... Detection brush, 16...
・Function generator. Agent Patent Attorney Akio Takahashi Kaya 1 Eye Kaya 2 Loaf Potato 3 Mouths $4 Diagram (Lofu Potatoes 6 Mouths (Inside Potatoes 7 Mouth Currents (″/-)

Claims (1)

[Claims] 1. A rotor equipped with an armature and a commutator, and a field core,
A main pole consisting of a field winding, a commutating pole iron core, a commutating pole winding, and a commutating pole consisting of a differentially wound auxiliary winding, and a brush are all provided. a detection brush for detecting voltage sound between the brush commutator pieces of the positive brush and the negative brush in a DC machine equipped with a fixed legge and transmitting and receiving power to the armature via the brush and the commutator; means for inputting all the detected voltages by the detection brush VC to a positive brush function generator and a negative brush function generator of different functions, and selecting one of the function generators according to the rotational direction of the armature; A rectification compensator for a DC machine, comprising means for controlling the amount of current in the auxiliary winding according to the result.