JPH0832197B2 - Eddy current brake controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an eddy current brake control device, and more particularly to an eddy current brake control device that is less affected by a load on a brake speed.

[Prior Art] In a conventional control device for an eddy current brake, an absolute deviation | Ef−Es | when | Ef |> | Es | is obtained by matching the speed command voltage Es and the speed feedback voltage Ef of the eddy current brake
The brake torque is proportional to the control. As shown in Fig. 5, if a high-speed command voltage Esh is given and then a deceleration command is given to the low-speed command voltage Esl, | Ef−Es
When | becomes large, a large torque is generated in the eddy current brake, and a large braking torque is instantaneously applied to the load, so that the speed of the load changes suddenly and a load shake occurs. In order to prevent this, as shown in FIG. 6, a certain high speed command voltage Esh that matches the high speed of the eddy current brake is set in advance, and when the low speed command voltage Esl is input, the speed command is Esh.
Gives a speed pattern for linear deceleration from to Esl. As a result, | Ef−Es | does not increase instantaneously, and it is possible to suppress the generation of large instantaneous braking torque. However, as shown in FIG. 7, the speed of the eddy current brake may fluctuate under the influence of the load or the like. At this time, if the low speed command voltage Esl is input, the high speed command voltage E for linear deceleration start
Since sh has a constant voltage, the actual speed of Esh and the eddy current brake do not match. Therefore, | Ef−Es | becomes large instantaneously, and the eddy current brake also generates large torque instantaneously, causing the speed of the load to be rapidly decelerated and causing the product to shake.

For general properties of eddy current braking, refer to "Electrical Engineering Pocketbook" (Ohm,
1973 edition page 3-14).

[Problems to be Solved by the Invention] In the above-mentioned conventional technology, when the speed of the eddy current brake fluctuates due to the influence of a load or the like, if the low speed command voltage is input instead of the high speed command voltage, the actual speed of the eddy current brake is changed. The speed is linearly decelerated from a certain constant high-speed command voltage, which was previously input regardless of the speed, toward the low-speed command voltage. As a result, there was the problem that the linear deceleration command voltage did not match the actual speed.

The object of the present invention is to start the linear deceleration start voltage from a value that matches the actual speed of the eddy current brake, no matter how the speed of the eddy current brake changes due to the influence of the load,
Ef−Es | does not momentarily increase, and a large brake torque does not occur instantaneously, and a stable brake torque is generated to provide a eddy current brake control device that prevents load fluctuations.

[Means for Solving Problems] The eddy current brake control device generates a brake torque proportional to | Ef−Es | when a low speed command voltage is input, that is, when | Ef |> | Es | An exciting voltage is applied to the eddy current brake, and the above operation is continued until | Ef−Es | ≈0. In this case, a speed generator that always generates a voltage proportional to the speed for detecting the speed Ef of the eddy current brake is used in combination. If the voltage generated by this speed generator is constantly detected and a high speed command voltage is created based on this voltage,
The high-speed command voltage for linear deceleration start can be commanded to a value that matches the actual speed of the eddy current brake. If a low-speed command voltage is input, this can be detected, and if the operation of the high-speed command is canceled, the actual speed will be reached. It is possible to perform linear deceleration from the matched high-speed command voltage toward the low-speed command voltage.

[Operation] A voltage proportional to the actual speed of the eddy current brake is constantly detected, and based on this voltage, the actual speed command circuit is operated so that the high-speed command voltage for linear deceleration start becomes a value that matches the actual speed, and the low-speed command When a voltage is input, the presence or absence of this is discriminated by a low speed command discrimination circuit, and the operation of the actual speed command circuit is stopped, and at the same time, a linear deceleration circuit that linearly decelerates from a high speed command voltage matching the actual speed to a low speed command voltage. If the speed of the eddy current brake fluctuates to any speed, the high-speed command voltage for starting the linear deceleration becomes a value that matches the actual speed.

[Embodiment] FIG. 1 shows a block diagram of an embodiment of the present invention. In addition to the conventional eddy current brake control circuit having a linear speed reduction circuit, an actual speed command circuit 7 and a low speed command determination circuit 8 are provided. While the load driver 9 is accelerating, relay RY
Does not take in the low speed command voltage Esl as input in the off state. In this case, a voltage Ef (AC) proportional to the speed of the eddy current brake is input to the actual speed command circuit 7, a high speed command voltage Esh that matches the actual speed is generated, and the linear speed reduction circuit 6 is input. Where Ef is the speed generator 4 of the eddy current brake 3
The speed is detected by the AC signal Ef (AC) at, and then converted into a DC signal by the AC / DC converter 31. on the other hand,
The linear deceleration circuit 6 changes the command voltage Es to the value of Esh according to the fluctuation of the actual speed until receiving the Esh and inputting the low speed command voltage, that is, until the linear deceleration is started. Hold. The difference between the command voltage Es and Ef is obtained by the subtractor 33, and this difference becomes a gate pulse through the automatic phase shifter (APPS) 30 to control the thyristor converter 32.

Next, when the relay RY is turned on to input the low speed command voltage Esl, the low speed command determination circuit 8 determines whether or not the low speed command voltage is input, and the operation of the actual speed command circuit 7 is stopped.
At the same time when Esh is set to zero, the linear speed reduction circuit 6 operates and
Linear deceleration is performed for a time T seconds set toward Esl. Therefore, according to the present embodiment, when a dolly subject to a negative load when traveling on a downhill or the like is decelerated by an eddy current brake, a large brake torque is not instantaneously generated even if the speed is increased due to a delay in brake torque generation. It has the effect of not causing shake.

Embodiments of plucking control and dynamic braking other than eddy current braking will be described with reference to FIGS. 3 and 4.
When decelerating the bogie by plucking braking as shown in Fig. 3, the phase shift control of the semiconductor elements 10 to 15
By switching to the 19-phase-shift control, the phases are switched and reverse rotation torque (braking torque) is generated. See also
When the vehicle is decelerated by dynamic braking as shown in the figure, the phase shift control of the semiconductor elements 20-25 is switched to the phase shift control of 20, 25, and a DC current is passed through the motor to generate braking torque. Even in the case of these two deceleration controls, the linear deceleration circuit 6, the actual speed command circuit 7, and the low speed command discrimination circuit 8 in FIG. A linear deceleration operation can be performed from the voltage, and the load does not shake.

EFFECTS OF THE INVENTION According to the present invention, no matter how the speed of the eddy current brake changes, the high speed command voltage for starting the linear deceleration is held at a value according to the actual speed, and the low speed command voltage is input. Since the linear deceleration from the actual high-speed command voltage to the low-speed command voltage can be performed in a time set as, the large brake torque is not generated instantaneously, and the load swing phenomenon is not caused without giving a shock to the load.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an embodiment diagram of the present invention, FIG. 2 is its time chart, FIGS. 3 and 4 are IM control example diagrams, and FIGS. 5 to 7 are conventional examples. It is a figure which shows the time chart of. 1 ... Speed commander, 2 ... Control device, 3 ... Eddy current brake, 4 ...
Speed generator, 5 ... Load, 6 ... Linear deceleration circuit, 7 ... Actual speed command circuit, 8 ... Low speed command discrimination circuit, 9 ... Load driver.

Claims (1)

[Claims] 1. A speed detecting means for detecting an actual speed voltage value proportional to an actual speed of an eddy current brake, and a high speed command voltage value and the speed which follow the actual speed voltage value detected by the speed detecting means at the time of a high speed command. A means for controlling the eddy current brake with a difference value from the actual speed voltage value detected by the detecting means, and the high speed command at the time of inputting the low speed command when the low speed command is input while operating with the high speed command. A linear deceleration means for linearly decelerating the command voltage value to a low speed command voltage value from the deceleration start point to a deceleration start point of the command voltage value, and a linear deceleration means for linearly decompressing the command voltage value. An eddy current brake control device comprising: means for controlling the eddy current brake by a difference value between the command voltage value and the actual speed voltage value detected by the speed detection means when the vehicle is decelerating.