JPS6022493A - Ignition controller of thyristor motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thyristor motor that drives a synchronous motor using a power converter, and in particular to an ignition control device for controlling the generation of an ignition signal at low speed in a thyristor motor that does not have a distributor. It is related to.

A conventional device of this type is shown in FIG. In the figure, 1 is a first converter that converts alternating current to direct current, and 2
is DC reactor, TU, TV.

TW, TX, TY, TZ are 6 constituting the second converter 6
one thyristor, four synchronous motors%U,V.

W is the armature winding of the synchronous motor 4, f is the field winding,
5 is a third coil connected to the field winding fi to convert alternating current to direct current.
It is a converter. 6 is a current command circuit, 7 is a current detector,
8 is a subtracter that takes the deviation between the current command signal that is the output of the current command circuit 6 and the detected output signal of the current detector 7; 9 is an amplifier that amplifies the deviation; A gate pulse phase shifter providing a gate pulse output signal to the first converter 1. 11 is a voltage detector that detects the terminal voltage of the synchronous motor 4; 12 is a current detector that detects each phase current flowing into the synchronous motor 4; 13 is a magnetic flux calculator that detects magnetic flux from the detected voltage and current; 14 Reference numeral 15 indicates a control advance angle command circuit that provides a control advance angle set value, and 15 indicates each thyristor TO, TV, TW, TX, TY, and TZ of the second converter 6 based on the magnetic flux detection value and the control advance angle set value.
This is a gate pulse generation circuit that generates a gate pulse output signal.

Next, the operation will be explained. The control system of the first converter 1 controls the gate of the first converter 1 by a current control system composed of a 'g current detector, a subtracter 8, an amplifier 9, and a gate pulse phase shifter 10. Performs pulse phase control. As a result, a current χ equal to the current command signal generated by the current command circuit 6 is caused to flow to the DC output side of the first converter 1 . Further, one system of the second converter 60 is composed of voltage and current detectors 11 and 12, a magnetic flux calculator 13, a control advance angle command circuit 14, and a gate pulse generation circuit 15. The magnetic flux is calculated from the voltage and current, and a constant control advance angle pulse is formed. FIG. 2 is a diagram explaining the operation of this part. The terminal voltage ewU of the synchronous motor 4 has a υ-swing due to armature leakage reactance and resistance, and in order to calculate the magnetic flux, from this voltage, the speed electromotive force Ewoo, which can be considered as a sine wave without υ-swing, is calculated. I need to take it out. Therefore, the magnetic flux calculator 16 first calculates the following equation.

However, here, %R: armature resistance, L: armature leakage reactance, I, IU: W-phase, U-phase armature current. The calculated speed electromotive force Ewoo is integrated and the synchronous motor 4
The instantaneous value Φwu of the internal magnetic flux is calculated. That is, Φwo ” f ” wuo dt ten ΦwU (0) However,
Here, ΦwU(0) is an initial value. The magnetic flux ΦWU is related to the speed (has a constant width. Let this amplitude be Φ.

On the other hand, the control lead angle command circuit 14 commands a value corresponding to ψMmβ as a lead angle command signal. Then, the gate pulse generation circuit 15 calculates the magnetic flux calculation results Φwu and ΦMI.
Comparing the
U's ignition pulse output signal S.

occurs. As a result, as is clear in the same figure.

An ignition pulse output signal whose phase is advanced by the phase difference β from the zero point of the speed electromotive force E□0 is obtained, and the control advance angle becomes β. In reality, there is a commutation type angle U, and the commutation margin angle r is γ=β−U. Therefore, in order to ensure the margin angle r, the control advance angle β is set to a value larger than the margin angle by one overlap angle U.

Since the conventional thyristor motor ignition control device is configured as described above, the integration error of the magnetic flux detector and the accuracy of the initial value become a problem, and the speed electromotive force itself becomes extremely small, especially in the low speed region. Therefore, this error became very large, and it was necessary to use a distributor to detect the magnetic pole position, especially during startup. In addition, the integrator has the drawback that it requires a complicated compensation circuit to reduce the error of the integrator, and further requires an initial value circuit to calculate the initial value, resulting in an extremely complicated configuration. Ta.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above. By creating an ignition pulse output signal from a magnetic ripple, the present invention aims to provide a thyristor motor ignition control device that does not require a distributor even in low-operation ranges.

An embodiment of the present invention will be described below with reference to the drawings. Third
In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts, so the explanation will be omitted. 100°200.500 is input with the terminal voltage eWtl# e, v, evw of the three-phase synchronous motor 4 detected by the voltage detector 11, and the pulse output signals G, U, Gsv, G, w and the pulse signal [ J
, V, and W, and each has the same configuration. Therefore, the internal configuration of 200°600 will be omitted and the explanation will focus on the terminal voltage ewt. The terminal voltage ewIJ passes through the bypass filter 16χ, enters the absolute value circuit 17, and then enters the one-shot circuit 20 through the low-pass filter 18 and the first comparison 519Y. on the other hand.

The output signal of the bypass filter 16 is differentiated by a differentiating circuit 22, and the result is input directly to a second comparator 24, while also being input to a third comparator 25 through a resilient inverter 26. . Each output signal of the comparators 24 and 25 is the first n-
It is input to the set terminal S and reset terminal R of the S flip-flop 26.

The output signal of the first comparator 20 is transmitted to the pulse generating circuit 100.
, and the output signal of the first R-S flip-flop 26 becomes the pulse signal U of the pulse generation circuit 100. Similarly, pulse output signals G0 and V are output from the pulse generation circuit 200, and qsw and W are output from the pulse generation circuit 600, respectively. 31, 32.3M, 34
, 35.56 is.

For example, the gate circuit 61 outputs an output under the AND condition of the pulse output signals G8IJ and U, while the gate circuit 32 outputs the output under the AND condition of the pulse output signals G8U and U.
Output under D condition? put out. Furthermore, 41.424t, 44.4
5.46 is the second R-S flip-flop, for example, the R-8 flip-flop 70 block 41 is set when the output signal of the gate circuit 61 falls from 1H1 to IL'', and the pulse output signal G3v is set at ILI''. It is reset when the IC changes from "H" to "H".

These pulse output signals “Is S*a SSs S4
p"5tS6 is each thyristor TU of the second converter 3
,TX.

This becomes the gate signal for TV, TY, TW, and TZ. 50 again
is the second gate circuit and pulse output signals GsU, G
If there is an output signal of sv, G, or w, that output signal GSi is sent out. This output signal GS is input to a subtracter 51. On the other hand, the subtracter 51 subtracts a predetermined value from the output deviation signal of the amplifier 9 only when the output signal GS is present, and then inputs the signal to the gate pulse phase shifter 10 .

Next, the operation will be explained. FIG. 4 is an explanatory diagram of the operation of the embodiment circuit of FIG. 3. In FIG. 4, ewU is a line voltage waveform diagram between the W phase and U phase of the terminals of the synchronous motor 4, and as shown, high frequency ripples are superimposed on the line voltage. This is because the DC output waveform of the third converter 5 for passing the field current has ripples that are an integral multiple of the power supply frequency, and this ripple voltage
This is because the voltage was induced in the terminal voltage on the armature side due to mutual induction between and the armature windings U, V, and W. 'Semi-J
- Lines U, V, W and field winding #! The magnitude of mutual induction with f M
varies depending on the relative positional relationship between the two windings, so as it rotates, the magnitude changes as shown in the figure. The mutual induction M is a sine function of the electrical angle θ, so when the rotor is rotating smoothly and at a constant speed, the magnitude of the ripple voltage changes sinusoidally, and the electrical phase O of the no-load induced voltage changes. It reaches its maximum at @, and reaches O at 90°.
becomes. Therefore, by observing the size of this ripple, the position χ of the rotor can be detected. The voltage ewu detected by the voltage detector 11 is input to the pulse generator 100. First, the filter 16 cuts out the low frequency components, leaving only the ripple components.

Thereafter, the absolute value t is obtained by the absolute value circuit 17, and the amplitude of the ripple is detected by applying a low-pass filter to the signal 18.

The output of the low-pass filter 18 is a full-wave rectified sine waveform whose phase is shifted by 90 degrees from the no-load induced voltage. Moreover, the amplitude is a value determined in advance from the ripple voltage generated by the third converter 5 and the maximum value of the mutual induction M. Now, let that value be the maximum value Eb. Comparator 19
compares the comparison level set at a value EaVC slightly smaller than the maximum value Eb with the output signal of the low-pass filter 18, and outputs a signal when the output signal of the filter 18 exceeds Eb. Based on this output, the one-shot circuit 20 outputs pulse output signals Gs and Y having a constant width. These signals G and U are output at intervals of 180° in the vicinity of 180° with respect to the electrical phase oO of the no-load induced voltage in phase with WU. Similarly, the signal G8v is the electric phase of the no-load induced voltage between the U phase and 1
The signal Gsw is output at around 80°, and the signal Gsw is output at around 180° from the electrical phase θ° of the no-load induced voltage between the VW phases.

These three-phase pulses are out of phase by 6C. The output signal S of the R-87 lip-flop 45 is set by the pulse output signal G8U, and at the fall of the signal G, i is set.
Output No. 8 Sl of the t-s flip-flop 41 is set. Since the output signal S1 of the It-8 flip-flop 41 is reset at 4B-@G□, it continues to be set for an interval of 120 degrees in electrical angle. Also it-s
Flip-flop 41°4S, 45. ! : Moni 1
80'', liC/I-satt, and sotL each operate with a phase difference of 1200/6.Meanwhile, the output of the bypass filter 16 is guided to the differentiator 22, where the time differential value is obtained.The third converter It is well known that the output voltage of No. 5 has a sawtooth ripple waveform. Therefore, the time differential value becomes a spike-like voltage at the rising edge of the sawtooth wave, and this changes in magnitude as the amplitude changes. This is because the electromagnetic coupling between the field winding, lJf, and the armature windings U, V, and W changes polarity as the rotor rotates.

As shown in the figure, the polarity χ of the differential value is also changed. This change in polarity occurs at an electrical angle of 90° of the no-load induced voltage.

The comparator 24 compares the minute positive voltage EC with the output of the differentiator 22, and when the output of the differentiator 22 exceeds EC, it outputs a pulse, and this pulse sets the 7 lip-flop 26χ. The comparator 25 compares the minute negative voltage EC with the result of inverting the polarity of the output of the differentiator 22, and the output of the inverter 26 is E. When the voltage is exceeded, a pulse is generated, and the 7 lip-flop 26 is reset by this pulse. Therefore, the output U of the R-87 lip-flop 26 is 180 degrees electrical angle of the no-load induced voltage.
In the vicinity, it is always in the mHI state, and in the vicinity of electrical angle 0°, it is always in the L state. By performing an AND logic with this output signal U in the gate circuits 61 and 62, if the output signal G8U is output near the electrical angle of 180 degrees of the no-load induced voltage,
Gate pulse S is issued and signal GsU is generated near electrical angle 0°.
When , the gate pulse S4 is issued. Below ■ phase W
Phases work similarly.

The output signal GS of the second gate circuit 50 is a signal G8t,
, Gav, G8w are output, that is, electrical angle 6
Outputs pulse output signals at 0° intervals. This pa/I/
The timing is synchronized with the switching of gate pulses S, ~S6. The subtracter 51 subtracts a predetermined amount χ from the reference value of the output signal of the amplifier 9, that is, the gate pulse phase of the first converter 1, every time the output signal GS arrives. As a result, the phase shifter 10
Is the phase reference signal input to very small? In response to this, the phase shifter 10 applies a gate pulse (usually 120') with a predetermined maximum delay angle to the first converter 1, which is limited to prevent commutation failure. Due to this gate pulse, the output voltage of the first converter 1 becomes a large negative value, and the DC current 'Do is narrowed down to O.

When the pulse output signal GS disappears, the current control system resumes normal operation, and 11! The DC current IDo is raised up to the reference current generated by the current command circuit 60.

As a result of the above operations, the phase currents of U phase and W phase ■. ,■1 is
In particular, K is shown in FIG. Although the phase (2) is not shown, it has a similar waveform. Note that %U phase current■. In addition, the no-load voltage EIJ of the U phase is shown by a broken line in the figure. As can be understood from the figure, it can be seen that the current and no-load voltage are almost in phase. By reducing the value of the comparison level Ea in the figure, the current phase can be advanced, and when the load is large, it is of course possible to prevent the power factor from deteriorating due to armature reaction. Also, comparison level E
If the value of a is made sufficiently small and the current phase is advanced, commutation by the internal induced voltage of the synchronous motor 4 becomes possible. In this case, the second gate circuit 50 and subtracter 51 are unnecessary.

FIG. 5 shows another embodiment of the gate pulse generating portion of the second converter of the present invention. In the figure, 101,201°601 is
This is a pulse generation circuit in which parts 100, 200, and 500 in FIG. 3 are omitted. Code 16°17.18, 19.20
is the same as that in Figure 3 (same as 201, 501)
also has the same configuration as 101. From these, pulse output signals Gs, J, Gsvt, .

Three-phase pulses of Gaw are output, input to the second gate circuit 50 , and guided to the subtracter 51 . This pulse output signal GS is simultaneously input to the hexadecimal ring counter 52. The ring counter 52 increments the count value by one each time the pulse output GS is input, and returns to the initial state every six increments. Therefore, there are six states in one cycle, and gate pulses are applied to the two thyristors corresponding to each state, as shown in FIG. As a result,
It is clear that gate pulses can be generated that have the same effect as the gate pulses 81 to S6 generated in the circuit of FIG.

In the embodiment of the present invention, the ripple included in the line voltage is used, but the same effect can be obtained by using the ripple included in the phase voltage or by shifting the phase of the detected voltage by appropriate operations. It is easy to obtain a gate pulse that works.

As described above, according to the present invention, the field ripple voltage included in the terminal voltage of the synchronous motor is detected and the ignition pulse output signal is generated, so that the magnetic pole position can be accurately determined even in the low speed region. This has the effect of making IW detection possible and eliminating the need for a distributor.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional thyristor motor ignition control device, FIG. 2 is an explanatory diagram of the operation of the device in FIG. 1, and FIG. 3 is a thyristor motor ignition control device according to an embodiment of the present invention. Configuration block diagram. 4 is an explanatory diagram of the operation of the embodiment shown in FIG. 3, FIG. 5 is a partial block diagram of a thyristor motor ignition control device showing another embodiment of the present invention, and FIG. 6 is an embodiment of the embodiment shown in FIG. 5. FIG. 1.3.5...Converter, 2...DC reactor, 4
...Synchronous motor, 6...Current command circuit, 7...Current detector, 8.51...Subtractor, 9...Amplifier, 1
0... Gate pulse phase shifter, 11... Voltage detector,
16.18...Filter, 17...Absolute value circuit, 1
9, 24, 25...Compare! , 20... One-shot circuit, 22... Differential circuit, 26... Polarity inverter, 2
6.41.42,43°44.45,46...Flip-flop% 31,32°33.34,35,36.
50...Gate circuit %52...Ring counter. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1 Figure 2 Whistle R#8A Figure 4 TOTZ TV TX TW TY Figure 6

Claims (4)

[Claims] (1) A first converter that converts alternating current to direct current, and
a second converter connected to the converter via a DC reactor to convert direct current to alternating current; and a second converter connected to the AC output terminal of the second converter and converting alternating current to direct current. In the ignition control device for a thyristor motor, which is configured with a synchronous motor having a field winding connected to a converter of No. 3,
a voltage detector that detects a voltage in an armature winding of the synchronous motor; a filter that removes low frequency components included in the output voltage of the voltage detector; an amplitude detector that detects the amplitude of the output signal of the filter; and a point in time when the detected amplitude of the output signal of the filter reaches a predetermined magnitude. and a timing circuit that detects the timing signal and outputs a timing signal, and derives each gate pulse signal to the thyristor provided in the second converter using three phases of the timing signal. Features: Thyristor motor ignition control device. (2) a polarity detector that generates a binary signal based on a comparison output signal that compares a differential value obtained by differentiating the output signal of the filter with a predetermined value; 2. The thyristor motor ignition control device according to claim 1, wherein respective gate pulse signals to a thyristor provided in said second converter are derived from three phase components of the signal. (3) having a hexadecimal ring counter that counts in synchronization with the three phases of the timing signal and generates a pulse output signal in a predetermined order, and performs the second conversion using the pulse output signal of the ring counter. 2. The ignition control device for a thyristor motor according to claim 1, wherein each gate pulse signal is derived to a thyristor provided in the thyristor motor. (4) A patent claim characterized in that the phase of the gate pulse signal given to a thyristor provided in the first converter is shifted to a predetermined phase angle by a predetermined time based on three phases of the timing signal. The ignition control device for a thyristor motor according to item 1.