JPS61214774A - Protecting system of power converter - Google Patents

Abstract

PURPOSE:To accelerate the protecting operation after a defect is detected by providing a protecting firing pulse output circuit and a firing pulse converter separately from a microcomputer. CONSTITUTION:A power converter has converters 1, 2, a motor 3, a position detector 4 and a speed detector 5, and the speed is controlled by a main microcomputer 8. When the defect detector 8 of the power converter detects a defect, the microcomputer 8 outputs a command (g) to perform a protecting operation for slave microcomputers 6, 7. In this case, protecting firing pulse generators 10, 11 which always have firing pulses, and firing pulse converters 12, 13 for switching the firing pulse from the microcomputers 6, 7 and the firing pulses from the generators 10, 11 by a firing pulse switching signal (h) are provided. Thus, after a defect is detected from a defect detector 9, both signals (g), (h) are immediately output to eliminate the influence due to the sampling delay of the microcomputer 8, thereby rapidly performing the protecting operation.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a protection system for a power converter that controls a power converter using a digital processing device such as a microcomputer (hereinafter simply referred to as a microcomputer). Regarding.

[Conventional technology]

In recent years, there has been an increase in the number of power conversion devices that utilize icon software, and some of these devices also use a microcomputer to control the phase of the ignition pulse for the power converter. FIG. 3 is a block diagram showing a conventional example of a power conversion device using a microcomputer. In the same figure,
1 and 2 are power converters, 3 is an electric motor, 4 is a position detector, 5
is a speed detector. The main microcomputer 8 performs speed control using the actual speed value, and sends a current command value and various operating information to the slave microcomputer 6, and a firing angle command value and various operating information to the slave microcomputer 7. Output each. Each slave microcomputer 6, 7 controls the power converter 1.2 according to instructions from the main microcomputer 8. In such a power converter, when the failure detection circuit 9 detects some kind of failure, this is notified to the microcomputer 8, which causes the microcomputer 8 to
Generally, a command is issued to perform a protective operation (for example, a pulse shift operation to reduce the current to zero).

[Problem that the invention seeks to solve]

In this case, when each microcomputer detects the occurrence of a failure and performs processing, there may be a delay due to sampling, and depending on the type of failure, there is a possibility that other failures may occur. Therefore, it is desirable to handle the failure as quickly as possible.

[Means for solving problems]

In a power conversion device using a microcomputer,
To provide a power conversion device protection system which is provided with a protective ignition pulse output circuit and an ignition pulse switching circuit, and can perform prompt failure processing without causing a sampling delay in a microcomputer when a failure occurs.

[Effect]

A discrete circuit (protective ignition pulse output circuit) is also used to generate a protection pulse for failure handling for the microcomputer-based control device, and in the event of a failure, the protection pulse from this discrete circuit is given priority over the software protection operation. Failure processing is carried out, and when the failure processing is completed, the ignition pulse from the microcomputer is returned to.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a time chart for explaining its operation. In FIG. 1, reference numeral 10.11 denotes a protective ignition pulse generation circuit that always prepares ignition pulses for the power supply side converter 1 and the motor side converter 2 in the phases in which protective operations are performed, respectively. Reference numeral 12 denotes a firing pulse switching circuit that switches between the firing pulse output from the microcomputer 6 and the firing pulse from the protective firing pulse generation circuit 10 in accordance with a firing pulse switching signal. This switching circuit 12 is used for the power supply side converter, whereas an ignition pulse switching circuit 13 is similarly provided for the motor side converter.

The microcomputer 8 performs a speed adjustment operation based on the speed command value and the actual speed value, and outputs a current command value to the microcomputer 6. The microconvenitor performs an adjustment operation according to the actual current value a and outputs an ignition pulse signal as a result. On the other hand, the microcomputer 7 outputs an ignition pulse signal in accordance with the control phase command to the motor side converter 2. At this time, an ignition pulse switching signal is given to the ignition pulse switching circuit 12.13 to select the ignition pulse from the microcomputer 6.7. An ignition pulse is output from the microcomputer 6.7 to control the motor.

If a system failure such as commutation failure occurs here, this is detected by the failure detection circuit 9 as shown in FIG. 2(b). Immediately after detecting the fault, the fault detection circuit 9 issues a fault detection signal g to the microcomputer 8 to notify the microcomputer 8 of the occurrence of the fault, and switches the ignition pulse to the ignition pulse from the protection ignition pulse generation circuit 10, 11. To achieve this, an ignition pulse switching signal as shown in FIG. 2(c) is output.

On the other hand, when the microcombiator 8 receives the failure detection signal g', it instructs each slave microcomputer 6.7 to perform a pulse shift. At this time, there is a possibility that the next ignition pulse after a failure cannot be pulse shifted due to a sampling delay in the computer 8 or a delay in commands to the slave microcomputer 6.7. In ~, the outputs of the ignition pulse switching circuits 12.13 are changed from the ignition pulses from the microcomputer 6.7 to the ignition pulses from the protective ignition pulse generation circuit 10.11, respectively, according to the ignition pulse switching signal. Figure 2 (e),
Switch as shown in (to). Therefore, the ignition pulse actually applied to each converter is pulse-shifted to the next ignition pulse after the failure occurs. In addition,
The shaded areas in Figure 2 (E) and (F) are the ignition pulse generation circuit 1
The protective ignition pulses from 0.11 are shown respectively. On the other hand, when the microcomputer 6.7.8 completes the protective operation such as pulse shift based on the failure detection signal g, that is, when it confirms that the current is zero, it sends a release signal i as shown in FIG. 2(d) to the failure detection circuit 9. Therefore, the failure detection circuit 9 turns off the ignition pulse switching signal accordingly. When the switching signal turns off, the ignition pulse switching circuit 12
．． 13 switches the ignition pulse from the protection III collapse ignition pulse generation circuit 10.11 to the ignition pulse from the microcomputer as shown in FIGS. At this point, the microcomputer side has also started its protective operation against failures, so no problems arise at this point. Thereafter, the micro combinator prepares for the next operation, such as operation after failure reset or automatic restart, and is ready for immediate transition.

By providing the protective ignition pulse output circuit and the ignition pulse switching circuit separately from one microcomputer in this way, it is possible to realize a prompt protective operation after a failure is detected.

〔Effect of the invention〕

According to the present invention, in a power converter device in which a microcomputer performs firing phase control of a power converter,
In addition to the ignition pulse control function (implemented by a microcomputer) for control, a protection ignition pulse generation circuit is provided that outputs only a protection ignition pulse, and when a failure occurs, it notifies the microcomputer. , the ignition pulse from the microcomputer is switched to the ignition pulse from the protective ignition pulse generation circuit for protection, and after the protection is completed, the ignition pulse is returned to the microcomputer, which is different from the conventional method. It is possible to perform a quick protection operation without the influence of sampling delay of the microcomputer, and also to be able to perform control by the microcomputer after the protection is completed.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of this invention, and FIG.
FIG. 3 is a time chart for explaining the operation shown in FIG. 3, and FIG. 3 is a configuration diagram showing a conventional example of a power converter protection system. Description of symbols 1...Power side converter, 2...Motor side converter, 3...Motor, 4...Position detector, 5... ...Speed detector, 6...Slave microcomputer for current control, 7...Slave microcomputer for pulse distribution, 8...Main microcomputer, 9
...Failure detection circuit, 10.11...Protective ignition pulse generation circuit, 12,13...Ignition pulse switching circuit, a...Current Actual value, b...
...actual speed value, C... synchronization signal, d...
...Position detector signals e, f...Ignition pulse,
g...Failure detection signal, h...Ignition pulse switching signal, i...Cancellation signal. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoshi Matsuzaki @Iv! '112 by electric train) 3rd reason for climbing the land

Claims (1)

[Claims] In a power conversion device in which at least the firing phase of the power converter is controlled by a predetermined digital control device, the power converter includes a failure detection means and a protective firing pulse generator that generates a firing pulse in a phase that protects the power converter. and an ignition pulse switching circuit that supplies either the protective ignition pulse or the normal ignition pulse outputted from the digital control device to the power converter as an ignition pulse, and when a failure occurs, The failure detection means notifies the digital control device of the occurrence of a failure, and also issues a command to the ignition pulse switching circuit to switch to a protective ignition pulse, and the digital control device performs this operation. A protection method for a power converter device, characterized in that the protection firing pulse is returned to the firing pulse from a digital control device by turning off the switching command after confirming that the switching command has been completed.