CN203326937U - Servo controller capable of self diagnosis of encoder faults - Google Patents

Abstract

The utility model discloses a servo controller capable of self diagnosis of encoder faults. The servo controller includes a pulse width processing circuit module which receives Z signals output by an encoder, a subcycle circuit module which receives AB signals output by the encoder, a comparison circuit module which determines whether the encoder has faults, and a memory which stores fault characteristic parameters of the encoder, corresponding fault type information and encoder related parameters, wherein the pulse width processing circuit module, the subcycle circuit module and the memory are all connected with the comparison circuit module. Thus, operation state of the encoder is detected in real time; once the encoder has a fault, the encoder is powered off and the fault is reported, and it is avoided that encoder faults cause signal loss to influence operation of a motor and cause possible severe results; in addition, the servo controller can realize both closed-loop self diagnosis and open-loop self diagnosis, which not only can carry out real-time protection under the condition that a servo driving system is in on-load operation, but also can detect the encoder when the motor is in zero load.

Description

A kind of servo controller with encoder fault self-diagnostic function

Technical field

The utility model relates to a kind of servo controller, a kind of servo controller with encoder fault self-diagnostic function of specific design.

Background technology

Incremental encoder is used widely in servo drive system as the position transducer of permagnetic synchronous motor, the positional information that the ABZ signal that servo controller in servo drive system feeds back according to incremental encoder and/or UVW signal obtain permanent-magnetic synchronous motor rotor, thus and carry out by this positional information the operation that the FOC algorithm is controlled motor.But incremental encoder is before operation or in servicely the faults such as the breakage of transducer original paper, Z phase signals loss, UVW signal error may occur, even may further cause the work disorder of servo drive system.In the servo drive system of present stage, these faults of encoder are not carried out to a real-time detection, diagnosis, control, there is leak on the fail safe when system is moved and accuracy.

The utility model content

Consider the problems referred to above of prior art, according to an aspect of the present utility model, comprising: have:

The pulsewidth processing circuit module of received code device output Z signal;

Minute all circuit modules of received code device output AB signal;

Judge the whether comparison circuit module of fault of encoder;

The memory of storage coder Fault characteristic parameters and corresponding failure type information and encoder relevant parameter;

Wherein, described pulsewidth processing circuit module, minute all circuit modules all are connected with the comparison circuit module with memory.

The utility model compared with prior art, one of the beneficial effects of the utility model are: the servo controller in servo drive system of the present utility model receives in real time to UVW signal and/or the ABZ signal of encoder output, the positional information that UVW signal and/or ABZ signal by real-time reception obtains rotor, thereby realize the real-time detection to the encoder running status, once shut down and report an error when encoder fault occurring, avoided because encoder fault causes signal deletion to affect the situation of motor operation and the generation of the serious consequence that may cause thus, in addition, method of the present utility model can realize closed loop self diagnosis and open loop self diagnosis, not only in the situation that real-time guard is carried out in the servo drive system load running, more can when empty load of motor, to encoder, be detected.

The accompanying drawing explanation

Fig. 1 shows the graph of a relation between incremental encoder AB signal and servo controller CNT count value;

Fig. 2 is shown the electric angle graph of a relation of incremental encoder UVW signal and rotor;

Fig. 3 shows the phase diagram between Z signal and UVW signal;

Fig. 4 shows according to implementing procedure during encoder closed loop self diagnosis and corresponding encoder fault in servo drive system of the present utility model;

Fig. 5 shows according to implementing procedure during encoder open loop self diagnosis and corresponding encoder fault in servo drive system of the present utility model.

Embodiment

Below in conjunction with drawings and Examples, the utility model is further illustrated, but execution mode of the present utility model is not limited to this.For complete understanding the utility model, numerous details have been mentioned in the following detailed description.But it should be appreciated by those skilled in the art that the utility model can realize without these details.In other example, be not described in detail known method, process, assembly and circuit, in order to avoid unnecessarily make embodiment fuzzy.

On the one hand, encoder fault self-diagnosing method in a kind of servo drive system comprises:

On servo controller, the line number of default encoder fault characteristic parameter and corresponding failure type information, input coding device;

Servo controller is controlled electric machine rotation, and receives in real time UVW signal and/or ABZ signal that institute's encoder that connects is exported;

Encoder fault characteristic parameter default on the UVW signal that receives in real time and/or ABZ signal and servo controller and/or the encoder relevant parameter of input are compared, judge whether fault of encoder;

Fault type, the output corresponding failure type information of confirming encoder are shown, and are stopped the servo drive system operation simultaneously;

Wherein, self-diagnosing method comprises closed loop self diagnosis and open loop self diagnosis, and during the closed loop self diagnosis, servo controller obtains the positional information of rotor by encoder, and after calculating, the voltage vector of motor operation is controlled in output.During the open loop self diagnosis, servo controller is directly exported the voltage vector of controlling the motor operation.In addition, during the closed loop self diagnosis, the operation of the motor load of servo drive system; During the open loop self diagnosis, the operation of the empty load of motor of servo drive system.

Further, default Fault characteristic parameters and corresponding failure type information comprise:

When encoder UVW signal is complete " 0 " or complete " 1 ", it is encoder UVW signal fault;

When encoder has the AB signal but AB signal numeration exceeds still without the output of Z signal, it is encoder Z signal fault;

When encoder Z signal normal but Z signal and UVW signal phase relation, not mating, is encoder UVW signal fault;

Excessive without numeration or counter value error when encoder AB signal, be encoder AB signal fault.

On the other hand, the utility model discloses a kind of servo-driver with encoder fault self-diagnostic function, it has:

The received code device is exported the pulsewidth processing circuit module of Z signal;

The received code device is exported minute all circuit modules of AB signal;

Judge the whether comparison circuit module of fault of encoder;

The memory of storage coder Fault characteristic parameters and corresponding failure type information;

Wherein, pulsewidth processing circuit module, minute all circuit modules all are connected with the comparison circuit module with memory.

In servo drive system of the present utility model, the encoder fault self-diagnosing method is based on following operation principle realization:

Permagnetic synchronous motor revolves and turns around, can export N (the line number that N is encoder) a-signal and B signal, the phase difference of 90 degree is wherein arranged between a-signal and B signal, and servo controller can pass through to compare the context of a-signal and B signal to obtain the rotating information of motor; For example, the incremental encoder of 2500 lines, it revolves and turns around 2500 a-signals of output and B signal, and servo-driver, by counting, processing to a-signal and B signal, obtains position and the rotating information of rotor; Show a-signal that incremental encoder exports and the relation between B signal and servo-driver CNT count value in Fig. 1.

Concrete, CNT produces counting at each rising edge and the trailing edge of a-signal and B signal, so the encoder that the line number is N mechanically rotates a circle, the actual 4N that answers of the count value of servo-driver inside; In addition, if the leading B signal of a-signal CNT counting upwards, otherwise a-signal hysteresis B signal CNT count downwards; Servo-driver obtains internal count value CNT by the detection to the AB signal, then with maximum count value 4N, compares the relative position information that obtains rotor.

During the closed loop self diagnosis, method of the present utility model is carried out implementing procedure as shown in Figure 4 and is exported corresponding encoder fault, and it comprises following content:

1, servo controller powers on; detect the UVW signal of encoder according to the phase relation between the Z signal shown in Fig. 3 and UVW signal; obtain initial electric angle; then control the motor operation according to instruction; continue to detect the UVW signal in running, as the state of " 1 " or complete " 0 " entirely appears in the UVW signal, illustrate that encoder UVW signal breaks down; should shut down processing, and show the corresponding failure code.

2, because the line number of encoder is determined, in running, the AB signal that number is definite just should appear in the every Z of appearance signal, and servo-driver judges by the number relation of confirming Z signal and AB signal whether encoder breaks down when operation.For example, the encoder of 2500 lines, 2500 AB signals should occur between 2 Z signals, and servo-driver adopts the counting mode in Fig. 1 to obtain corresponding CNT value and should be 10000; If the CNT counting error between 2 Z signals thinks that between +/-0.03% the AB signal is correct, otherwise think the AB signal fault; Be greater than N * 10000(N if there is the CNT counting and get 2,3 ...), still there is no the output of Z signal, think the Z signal fault;

3, servo controller is in operation, and detecting under the normal prerequisite of Z signal, the UVW signal is detected.Because once the number of pole-pairs of motor is determined; the Z signal of its encoder output and the phase place corresponding relation of UVW signal are also determined with regard to unique; by detecting after the Z signal occurs the edge up and down of the UVW immediately occurred; according to the phase diagram between the Z signal shown in Fig. 2 and UVW signal; judge that CNT value between each edge and Z signal is whether within zone of reasonableness; if exceed zone of reasonableness think and need the UVW signal fault to shut down and process, and show the corresponding failure code.

Above content is carried out in real time when servo controller is controlled the motor operation, when the feedback signal that servo controller sends according to encoder is controlled the operation of motor, carries out in real time, once break down, shuts down and reports an error at once.

During the open loop self diagnosis, method of the present utility model is carried out implementing procedure as shown in Figure 5 and is exported corresponding encoder fault, and it comprises following content:

After entering the open loop diagnostic mode, servo controller is first exported the current phasor of the control motor rotation of a fixed amplitude according to the frequency f of setting, under the operating mode that encoder is operated in synchronously drag due to the effect of this current phasor, its running frequency is relevant to the frequency f of this current phasor; Then the ruuning situation of encoder is carried out to real-time detection, concrete,

The Current Vector Control motor operation of the frequency f of 1, sending according to servo controller, the lasting UVW signal that detects encoder in running, as the state of " 1 " or complete " 0 " entirely appears in the UVW signal, illustrate that encoder UVW signal breaks down.

2, run unit time T (getting T=1/f), obtain CNT count value by encoder AB signal at T in the time, and relatively CNT and CNT_T(mechanically rotate the CNT numerical value of one week), if error exceeds 10%, the AB signal fault is described.

3, in the normal situation of AB input, judge by confirming the number relation between Z signal and AB signal whether the Z signal of encoder breaks down, determination methods is identical during with the closed loop self diagnosis.

4, in the normal situation of Z input, the UVW signal is detected, determination methods is identical during with the closed loop self diagnosis.

Above content is carried out in real time when servo controller is directly controlled the motor operation, and motor does not need the feedback signal of encoder directly to move under this pattern, and now preferably guarantees that motor is no-load running.In addition, can select to make servo drive system enter the open loop diagnostic mode by the button arranged on servo controller, simple and convenient.

By above Detection of content prejudge encoder whether normal after, then servo drive system is come into operation, guaranteed the safety and reliability of system.

Claims (1)

1. the servo controller with encoder fault self-diagnostic function is characterized in that having:

The pulsewidth processing circuit module of received code device output Z signal;

Minute all circuit modules of received code device output AB signal;

Judge the whether comparison circuit module of fault of encoder;

The memory of storage coder Fault characteristic parameters and corresponding failure type information and encoder relevant parameter;

Wherein, described pulsewidth processing circuit module, minute all circuit modules all are connected with the comparison circuit module with memory.

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