JP2005253215A - Power flow control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power flow control device capable of achieving large resistance to transitional heavy-current, such as defective current of a rotary type transformer, eliminating generation of a higher harmonic wave, achieving reductions in loss and cost, and free maintenance by using the rotary type transformer having a stopper device as device equipment of the power flow control device. <P>SOLUTION: This power flow control device is constituted of the rotary type transformer having a rotor jointed with a first alternate current power system and a stator jointed with a second alternate current power system; the stopper device which restricts a rotational angle range of the rotor, a driving motor which drives the rotor; a flow controller which compares current transit power with the prescribed transit power of the rotary type transformer to calculate an angular speed command value of the rotor; and a torque controller which adjusts an output torque of the driving motor based on the angular speed command value and the angular speed of the rotor. The rotational angle of the rotor is adjusted while being restricted to the prescribed rotational angle range by the stopper device, thus controlling the current transit power so as to become the prescribed transit power. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a power flow control device using a rotary transformer between power systems.

  Conventionally, the power flow can be adjusted by performing line reactance compensation as a power flow controller that is connected in series between the power transmission unit and the power reception unit of the AC power system and adjusts the power flow between the power transmission unit and the power reception unit. Such variable series capacitors and phase adjusters that adjust the power flow by adjusting the voltage phase difference between the buses have been put into practical use.

  For example, A.J.F.KERI and others have introduced a switched capacitor system which is an embodiment of a variable series capacitor (Non-Patent Document 1). In this switched capacitor system, a thyristor switch connected in parallel to a plurality of series capacitors is turned on and off to vary the capacitance through which the line current passes.

  A.J.F.KERI and others also introduce a thyristor-controlled series capacitor system which is an embodiment of a variable series capacitor (Non-patent Document 1). In this thyristor-controlled series capacitor system, a thyristor control reactor is connected in parallel to the series capacitor, the firing angle of the thyristor is controlled, and the combined reactance with the capacitor is continuously controlled.

  Moreover, Ichiro Ankai et al. Show one embodiment of a phase adjuster. A series transformer that applies a phase adjustment voltage between a power transmission unit and a power reception unit, an adjustment transformer that supplies the phase adjustment voltage to the series transformer, and a tap changer (non-patent document 2). ).

 The power flow control system that controls the power flow with each of the power flow controllers such as the variable series capacitor and the phase adjuster described above detects and inputs the power flow of the line for power flow adjustment in the power system, and inputs the power flow. In order to realize a line power flow equivalent to the power flow command value with zero deviation from the command value, an operation amount of the power flow controller is output.

 The amount of operation of the power flow controller is, for example, an ON / OFF signal of each thyristor switch in the switched capacitor method, a thyristor firing angle in the thyristor controlled series capacitor method, and a tap point or It is a phase adjustment voltage command value or the like.

 In each power flow controller described above, the power flow can be adjusted by the operation amount output from the power flow control system corresponding to each device.

On the other hand, in recent years, a method has been reported in which a rotational transformer is used between power systems, the rotational speed of the rotating transformer is controlled, and the frequency deviation between the systems is adjusted (Patent Document 1).
JP-A-9-23587 MPROVING TRANSMISSION SYSTEM PERFORMANCE USING CONTROLLED SERIES CAPACITORS; Cigre 1992 AJFKERI, et.all Ichiro Yasumi and others "275kV, 1000MVA phase adjuster" The Institute of Electrical Engineers of Japan 1985 National Convention

  In conventional power flow control, the phase shift adjuster realizes power flow control by tap adjustment by a tap changer, so it is not suitable for applications that finely adjust power flow, and the operation speed is slow. there were.

  In addition, it is necessary to frequently maintain the tap changer, and there is a problem that operation costs are increased.

  Moreover, although the method of adjusting continuously at high speed using the power converter which applied power electronics is also considered, there existed a problem that cost became high and loss was relatively large.

  Further, since this power converter generates harmonics due to the switching operation of the semiconductor element, a power filter that reduces the outflow of the harmonics to the power system is necessary, and there is a problem that the installation site is difficult and the cost is high. It was.

  Furthermore, since the semiconductor element is generally unsuitable for passing a large current, a protection device for protecting the semiconductor element against a failure current generated in the event of a system failure is necessary, and immediately when the system failure occurs. There was a problem that it was impossible to control the power flow.

  Therefore, the present invention uses a rotary transformer provided with a stopper device as an element device of the power flow control device, has a large tolerance against a transient large current such as a fault current of the rotary transformer, and generates harmonics. Another object is to provide a low-loss, maintenance-free and low-cost power flow control device.

  Specifically, the rotary transformer, which is the main device in the power flow control device, sets a stopper device to limit the rotation angle range and performs maintenance by rotating in both directions within the limited angle range. A device that reduces and further enhances the control system to compensate for the nonlinear relationship between the rotor rotation angle of the rotary transformer and the active power passing through the rotary transformer, and a device that limits the rotor rotation angle Another object is to provide a damping improvement control device for frequency and voltage fluctuations.

  To achieve the above object, the power flow control device according to claim 1 includes a rotor and a stator, the rotor is coupled to the first AC power system, and the stator is the second AC. A rotary transformer coupled with the power system, a stopper device that limits the rotation angle range of the rotor, a drive motor that drives the rotor, and the current passing power and the predetermined passing power of the rotating transformer are compared, It consists of a power flow controller that calculates the angular velocity command value of the rotor, and a torque controller that adjusts the output torque of the drive motor from the angular velocity command value and the angular velocity of the rotor. It is characterized in that the current passing power can be controlled to a predetermined passing power by adjusting in a state limited to a predetermined rotation angle range by the apparatus.

  Further, the power flow control device according to claim 2 is the power flow control device according to claim 1, wherein the power flow controller is configured to adjust the voltage of the first bus connecting the rotor and the first AC power system. Taking the magnitude and the magnitude of the voltage of the second bus connecting the stator and the second AC power system, the voltage phase difference between the first bus and the second bus corresponding to the predetermined passing power, and the current pass A voltage phase difference deviation between a voltage phase difference between the first bus and the second bus corresponding to electric power is calculated, and an angular velocity command value of the rotor is calculated from the voltage phase difference deviation.

  According to a third aspect of the present invention, there is provided the power flow control device according to the first aspect, wherein the power flow controller is configured to increase the voltage of the first bus connecting the rotor and the first AC power system. And the magnitude of the voltage of the second bus connecting the stator and the second AC power system and the reactive power value passing through the first bus or the second bus, and the first bus and the second corresponding to the predetermined passing power The voltage phase difference deviation between the voltage phase difference between the two buses and the voltage phase difference between the first bus and the second bus corresponding to the current passing power is calculated, and the angular velocity command value of the rotor is calculated from the voltage phase difference deviation. It is characterized by doing.

  The power flow control device according to claim 4 is the power flow control device according to any one of claims 1 to 3, wherein the power flow controller takes in a rotation angle of the rotor and uses the rotation angle. A rotation angle soft limiter that calculates a predetermined rotation angle of the rotor corresponding to the predetermined passing power and outputs the rotation angle by limiting the predetermined rotation angle within a set angle range. An angular velocity command value of the rotor is calculated from the rotation angle.

  The power flow control device according to claim 5 is the power flow control device according to any one of claims 1 to 4, wherein the power flow controller captures the rotation angle of the rotor and is proportional to the rotation angle. A value calculated via an element or a differential element is added to the angular velocity command value, and the angular velocity command value is limited to a value within a predetermined angular velocity command value range and output.

  A power flow control device according to claim 6 is the power flow control device according to any one of claims 1 to 5, according to the system state of the AC power system to which the rotary transformer is coupled. And a command change rate limiting circuit for changing the predetermined rate of change of the predetermined passing power and outputting the predetermined passing power within the range of the rate of change limitation.

  A power flow control device according to claim 7 is the power flow control device according to any one of claims 1 to 6, wherein a gain element, a phase compensation element, and a current passing power of the rotary transformer are provided. The value calculated through the incomplete differential element is added to the predetermined passing power.

  The power flow control device according to claim 8 is the power flow control device according to any one of claims 1 to 6, wherein the first AC power system or the second power transformer to which the rotary transformer is coupled. And the value calculated through the gain element, the phase compensation element, and the incomplete differential element is added to the predetermined passing power.

  A power flow control device according to a ninth aspect is the power flow control device according to any one of the first to sixth aspects, wherein the first AC power system or the second power transformer to which the rotary transformer is coupled. The value calculated through the gain element, the phase compensation element, and the incomplete differential element is added to the predetermined passing power, taking in the magnitude of the bus voltage of the AC power system.

  A power flow control device according to a tenth aspect of the present invention is the power flow control device according to any one of the first to ninth aspects, wherein the rotor is connected to the first AC power system or the stator. And a second AC power system. A power flow control device, wherein a capacitor is connected between the connection bus and the ground or a three-phase line.

  The power flow control device according to claim 11 is the power flow control device according to any one of claims 1 to 10, wherein the rotor winding and the first AC power system are lengthened. It is characterized by being connected with a conducting wire with a margin.

  The power flow control device of the present invention uses a rotary transformer as an element device of the power flow control device, has a large tolerance against a transient large current such as a fault current of the rotary transformer, and has no generation of harmonics. In addition, it is possible to provide a power flow control device that utilizes the features of low cost and low loss.

  Furthermore, the present invention is characterized in that the rotary transformer, which is the main equipment in the power flow control device, sets a stopper device to limit the rotation angle range and rotates in both directions within the limited angle range. In addition, the control system is strengthened to compensate for the nonlinear relationship between the rotor rotation angle of the rotary transformer and the active power passing through the rotary transformer, and to limit the rotor rotation angle It is possible to provide a device, a damping improvement control device for frequency and voltage fluctuations, and the like.

  Examples will be described below.

  FIG. 1 is a configuration diagram of a power flow control device corresponding to the first embodiment of the present invention. In FIG. 1, a rotary transformer 101 has a rotor 101R and a stator 101S, and the rotor 101R is connected to the first AC power system 10 by three-phase lines RR, SR, TR included in the power transmission line 20. The stator 101S is connected to the second AC power system 11 by the three-phase lines RS, SS, TS included in the power transmission line 21.

  Note that the connection between the first AC power system 10 and the second AC power system 11, and the rotor 101R and the stator 101S may be reversed. In FIG. 1, the first AC power system 10 and the second AC power system 11 are connected only via the rotary transformer 101, but together with the rotary transformer 101, other than the rotary transformer 101. It may be connected to a power transmission line.

  In addition, as shown in FIG. 1, when the first AC power system 10 and the second AC power system 11 are connected only via the rotary transformer 101, the AC fundamental frequency is the same. However, the phases may be different.

  A drive motor 30, a speed detector 32, and an angle detector 33 are connected to the rotor 101R. The drive motor 30 may drive the rotor 101R directly or may be connected to the rotor 101R via a gear.

  The rotor 101R and the stator 101S are provided with convex stopper devices 31 that are locked to each other. By increasing the number of locations where the stopper devices 31 are installed, the rotation angle is set at a set rotation angle of 360 degrees or less. Rotation can be limited.

  The control device 200 includes a power flow controller 201, a torque controller 202, and a power transducer 203. The operating speed of the power flow controller 201 is lower than the operating speed of the torque controller 202. That is, the control speed of the power flow controller 201 is lower than the control speed of the torque controller 202.

  The power flow controller 201 receives a signal representing the passing power P of the power transmission line 20 measured by the power transducer 203 transmitted from the power transmission line 20. In the power flow controller 201, the active power command input signal Pref is set, and the difference (Pref−P) between the power command input signal Pref and the passing power P is integrated with the proportional element 304a, for example, as shown in FIG. Processing is performed through the PI control circuit 304 including the element 304 b and the limiter element 304 c, and the rotational speed command signal ωref is output to the torque controller 202.

  The torque controller 202 receives the angular velocity ωR of the rotor 101 </ b> R from the speed detector 32 and outputs a drive torque signal T to the drive motor 30. Generation of the drive torque signal T is equivalent to generally used motor speed control, and thus detailed description thereof is omitted.

  FIG. 3 is a detailed configuration diagram of the rotary transformer 101. The rotary transformer 101 includes a rotor 101R and a stator 101S. It is assumed that the windings of the rotor 101R and the stator 101S have rated values that allow maximum power to pass. The rotor 101R includes a slip ring 102 and a rotor basket 103.

  The three-phase lines RR, SR, TR from the first AC power system 10 are connected to the slip ring 102, and the three-phase lines RS, SS, TS from the second AC power system 11 are connected to the stator 101S. It is connected to the. The rotor 101R is provided with a speed detector 32 and an angle detector 33 in the vicinity thereof, and generates an angular velocity ωR of the rotor 101R and an angle θR of the rotor 101R with respect to the stator 101S.

  In FIG. 3, the rotor 101R is a rotor winding RR +, SR +, TR +, RR−, SR−, TR− spaced at 60 degrees, and the stator 101S is a stator winding RS +, SS + spaced at 60 degrees. , TS +, RS−, SS−, TS−, the number of pole pairs is 1. The configuration principle of the present invention can be applied to a rotary transformer having two or more phases. The rotor 101R is rotatable in both clockwise and counterclockwise directions with the axis RAX as the central axis. The rotor 101R is rotationally driven by a drive motor 30 coupled to the rotor 101R.

  It is assumed that the angle θR when RR + and SR + are accurately aligned is zero, and the output of the angle detector 33 is calibrated.

  A stopper device 31 that locks the rotor 101R and the stator 101S is installed. As shown in FIG. 1, the stopper device 31 will be described as having a protrusion shape as an example. When the protrusions of the rotor 101R and the protrusions of the stator 101S are in contact with each other, an angular range in which the rotor 101R can rotate is limited. If there is one protrusion on each of the rotor 101R and the stator 101S, the angle can be changed within a range of one rotation. The drive motor 30 rotates the rotor 101R in response to the drive torque signal T from the torque controller 202. The polarity of the drive torque signal T depends on whether power flows from the first AC power system 10 to the second AC power system 11 or vice versa. Depending on the amplitude of the drive torque signal T, the rotational speed of the drive motor is increased or decreased.

  As described above, desired power (power command input signal) Pref is transmitted between the first AC power system 10 and the second AC power system 11 via the rotary transformer 101, and power to be measured. The drive motor 30 given the torque command T from the control device 200 adjusts the angle θR of the rotor 101R of the rotary transformer 101 with respect to the stator 101S so that P and Pref match.

The power transmission by the rotary transformer 101 passes through the rotary transformer 101, that is, the active power passing through the power transmission line 20 is P, the voltage of the power transmission line 20 is V1, and the voltage of the power transmission line 21 is large. The phase angle of the transmission line 20 with respect to the voltage phase reference is θ1, the phase angle of the voltage of the transmission line 21 with respect to the voltage phase reference is θ2, the phase angle of the rotor 101R with respect to the stator 101S is θr, and the transmission line 20 When the total reactance between the power transmission line 21 and the power transmission line 21 is Xtr, and the turn ratio of the winding turns of the stator 101S to the winding turns of the rotor 101R of the rotary transformer 101 is n, the active power P is expressed by the following equation (1). It is represented by
P = (n × V1 × V2 / Xtr) sin (θ1 + θr−θ2) (1)
In the present invention, the phase angle represents an electrical angle. As is well known, between the electrical angle and the mechanical angle,
Electrical angle = number of pole pairs x mechanical angle (however, the number of pole pairs = number of poles / 2) (2)
There is a relationship.

Therefore, as can be seen from the equation (1), the active power P passing through the rotary transformer 101 has a characteristic affected by the phase angle θr of the rotor 101R with respect to the stator 101S. The passing power can be set to the command value Pref by measuring the passing effective power P and continuously variably adjusting the rotation speed command ωref of the rotor 101R according to the comparison amount with the desired passing effective power Pref. it can. However, the maximum value Pmax in equation (1) is
Pmax = V1 × V2 / Xtr (3)
Therefore, the active power command value Pref to be given to the power flow controller 201 should be limited to Pmax or less.

  According to the present embodiment, the control device 200 adjusts the rotation angle θR of the rotor 101R with respect to the stator 101S, and continuously fines the effective power passing through the rotary transformer 101 within a possible rotation angle range. Can be adjusted.

  FIG. 4 is a configuration diagram of the power flow controller 201 corresponding to the second embodiment of the present invention. Except for the power flow controller 201, the description is omitted because it is the same as the description in the first embodiment.

  The power flow controller 201 includes an active power command input signal Pref, a passing power P of the power transmission line 20 measured by the power transducer 203, a voltage magnitude V1 of the power transmission line 20, and a voltage magnitude V2 of the power transmission line 21. And the rotational speed command signal ωref is output to the torque controller 202.

  Further, the power flow controller 201 limits the active power command input signal Pref to the upper and lower limit values Pmax and Pmin set by the power command limiter 301, outputs Pref, and transmits it to the phase difference calculator 302a. . In general, Pmin has an opposite sign to Pmax, and Pmax can be calculated by equation (3).

The first phase difference calculator 302a receives the output Pref of the power command limiter 301, the voltage magnitude V1 of the power transmission line 20, and the voltage magnitude V2 of the power transmission line 21, and the phase of the voltage of the power transmission line 20 “Θ1 + θrref−θ2”, which is composed of the angle θ1, the phase angle θ2 of the voltage of the transmission line 21 and the phase angle θrref of the rotary transformer 101 when the passing effective power of the transmission line 20 is Pref, Is calculated by the equation (4), which is an equivalent equation, and output. The expression (4) can be easily derived by referring to the expression (1).
θ1 + θrref−θ2 = arc sin (Xtr × Pref / (n × V1 × V2)) (4)

The passing effective power P of the power transmission line 20 measured by the power transducer 203 is transmitted to the second phase difference calculator 302b. In the second phase difference calculator 302b, the passing effective power of the power transmission line 20 input to the first phase difference calculator 302a is Pref. However, the only difference is that this is the passing effective power P of the power transmission line 20. And the phase angle θ1 of the voltage of the power transmission line 20, the phase angle θ2 of the voltage of the power transmission line 21, and the rotary transformer 101 when the effective power passing through the power transmission line 20 is P in the equation (5). “Θ1 + θr−θ2” composed of the phase angle θr is calculated and output.
θ1 + θr−θ2 = arc sin (Xtr × P / (n × V1 × V2)) (5)

The output of the second phase difference calculator 302b is subtracted from the output of the first phase difference calculator 302a, and Δθr in equation (6) is calculated and transmitted to the PI control circuit 304.
Δθr = (θ1 + θrref−θ2) − (θ1 + θr−θ2) = θrref−θr (6)
As shown in the equation (6), Δθr is the rotation of each rotary transformer 101 when the passing active power of the transmission line 20 is the command value Pref and when the passing effective power P of the transmission line 20 is the current passing active power P. It represents the child rotation (electrical) phase, the deviation between θrref and θr.

  In the PI control circuit 304, Δθr is input, and as shown in FIG. 2, the rotational speed command signal ωref is calculated via the proportional element 304a, the integral element 304b, and the limiter element 304c in the PI control circuit 304. As shown in FIG. 4, it is transmitted to the rotation speed command limiter 305. The rotation speed command limiter 305 outputs the input rotation speed command signal ωref within the range between the upper and lower limit values ωrefmax and ωrefmin of the rotation speed command.

  According to such a configuration, the rotary transformer 101 having a non-linear relationship of the sine function (sin) expressed by the equation (1) with respect to the passing active power set value Pref and the passing active power P of the transmission line 20. , The phase angle deviation Δθr of the rotor 101R with respect to the stator 101S can be calculated, and the phase angle deviation Δθr can be controlled to approach zero, and the transmission line 20 can be controlled within a large change range of the phase angle θr. A constant control performance can be obtained without being influenced by the nonlinear characteristics of the passing power P and the phase angle θr of the rotor 101R.

FIG. 5 is a configuration diagram of the power flow controller 201 corresponding to the third embodiment of the present invention. The difference from the second embodiment is the acquisition of the passing reactive power Q of the first phase difference calculator 302c, the second phase difference calculator 302d, and the transmission line 20 shown in FIG. When Rtr is a total resistance between the transmission line 20 and the transmission line 21, and the passing reactive power of the transmission line 20 is Q, the passing active power P of the transmission line 20 expressed by the equation (1) is further detailed as (7 ) Expression.
P = (n × V1 × V2 / Xtr) sin (θ1 + θr−θ2) + (Rtr / Xtr) × Q (7)

The first phase difference calculator 302c includes the output Pref of the power command limiter 301, the voltage magnitude V1 of the power transmission line 20, the voltage magnitude V2 of the power transmission line 21, and the passing reactive power Q of the power transmission line 20. , And the phase angle θ1 of the voltage of the power transmission line 20, the phase angle θ2 of the voltage of the power transmission line 21, and the phase angle θrref of the rotary transformer 101 when the effective power passing through the power transmission line 20 is Pref. The following “θ1 + θrref−θ2” is calculated by the equation (8) that is equivalent to the equation (7) and output.
θ1 + θrref−θ2 = arc sin ((Xtr × Pref−Rtr × Q) / (n × V1 × V2)) (8)

The passing effective power P of the power transmission line 20 measured by the power transducer 203 is transmitted to the second phase difference calculator 302d. In the second phase difference calculator 302d, the passing effective power of the power transmission line 20 input to the first phase difference calculator 302c is Pref. However, the only difference is that this is the passing effective power P of the power transmission line 20. In equation (9), the phase angle θ1 of the voltage of the power transmission line 20, the phase angle θ2 of the voltage of the power transmission line 21, and the rotary transformer 101 when the effective power passing through the power transmission line 20 is P. “Θ1 + θr−θ2” composed of the phase angle θr is calculated and output.
θ1 + θr−θ2 = arc sin ((Xtr × P−Rtr × Q) / (n × V1 × V2)) (9)

  According to such a configuration, the rotary transformer 101 having a non-linear relationship of the sine function (sin) expressed by the equation (7) with respect to the passing active power set value Pref and the passing active power P of the transmission line 20. The phase angle deviation Δθr of the rotor 101R with respect to the stator 101S can be calculated, and the phase angle deviation Δθr can be controlled to approach zero, and the resistance component included in the leakage impedance of the rotary transformer 101 can be controlled. Even when the resistance of the transmission line is large, constant control is possible without being affected by nonlinear characteristics between the passing power P of the transmission line 20 and the phase angle θr of the rotor 101R in a large change range of the phase angle θr. Performance can be obtained.

  FIG. 6 is a configuration diagram of the power flow controller 201 corresponding to the fourth embodiment of the present invention. The difference between the second embodiment and the third embodiment is that, as shown in FIG. 6, the rotation angle soft limiter 306, the rotation angle conversion gain 307, and the angle detection connected to the vicinity of the rotor 101R of the rotary transformer 101. The rotation angle θR detected by the device 33 is captured. The angle detector 33 will be described as detecting the mechanical angle θR of the rotor 101R.

The mechanical angle θR of the rotor 101R detected by the angle detector 33 is input to the rotation angle conversion gain 307. In the rotation angle conversion gain 307, the electrical rotation angle (phase angle) θr of the rotor 101R is calculated by Equation (2) according to the number of poles of the rotary transformer 101. The rotation angle θr is the difference Δθr between the first phase difference calculator 302a and the second phase difference calculator 302b of the second embodiment or the first phase difference calculator 302c and the second phase difference of the third embodiment. Is added to the difference Δθr with respect to the device 302d, and (θr + Δθr) is input to the rotation angle soft limiter 306.

  When (θr + Δθr) input to the rotation angle soft limiter 306 is expressed by the equation (6) described in the second embodiment, Δθr is expressed as the passing effective power P of the transmission line 20 is the command value Pref. Is equivalent to the rotor rotation (electrical) phase θrref of the rotary transformer 101 in FIG.

  The rotation angle soft limiter 306 limits and outputs the input signal (θr + Δθr) within the range of the upper and lower limits θrrefmax and θrrefmin of the (electrical) rotor rotation phase set therein. The subtraction value obtained by subtracting the output value of the rotation angle conversion gain 307 from the output value of the rotation angle soft limiter 306 is input to the PI control circuit 304 in the second embodiment or the third embodiment.

  According to such a configuration, the rotor rotation (electrical) phase θrref of the rotary transformer 101 when the passing effective power P of the transmission line 20 is the command value Pref is calculated and rotated by the rotation angle soft limiter 306. Since it is possible to control the rotational phase θr by limiting the phase θrref within the set range, the mechanical shock when the rotation angle is limited by the stopper device 31 is alleviated, and the life and maintenance cycle of the stopper device 31 are reduced. It is possible to extend the operation cost and reduce the operation cost.

  FIG. 7 is a configuration diagram of a control device 200 corresponding to the fifth embodiment of the present invention. The control device 200 includes a power flow controller 201, a torque controller 202, and a power transducer 203 in the first to fifth embodiments, and a proportional / differential (PD) control circuit 308.

  The proportional differential control circuit 308 takes in the rotation angle θR detected by the angle detector 33, adds the values obtained by passing the proportional element and the differential element in parallel, and outputs the result. A value obtained by subtracting the output value of the proportional differential control circuit 308 from the output ωref of the power flow controller 201 is transmitted to the torque controller 202.

  According to such a configuration, a feedback compensation loop is configured by the proportional differential control circuit 308 for the torque controller 202, the drive motor 30, and the rotary transformer 101. Therefore, the dynamic characteristics of the torque controller 202, the drive motor 30, and the rotary transformer 101 can be changed by adjusting the proportional gain and the differential element gain of the proportional differential (PD) control circuit 308.

  The control speed of the power flow controller 201 is slower than the control speed of the torque controller 202, and according to this embodiment, the dynamic characteristics of the torque controller 202 can be adjusted without affecting the dynamic characteristics of the power flow controller 201. Therefore, the dynamic characteristics of the power flow controller 201 and the dynamic characteristics of the torque controller 202, the drive motor 30, and the rotary transformer 101 can be adjusted in coordination, and the dynamic characteristics of the power flow control device can be improved. A high-performance power flow control device can be obtained.

  FIG. 8 is a configuration diagram of the power flow controller 201 corresponding to the sixth embodiment of the present invention. The difference from the first to third embodiments is that the active power command input signal Pref is input to the change rate limiting circuit 400, and the output of the change rate limiting circuit 400 is the active power command in the first to third embodiments. The input signal Pref is changed.

  Further, the change rate limiting circuit 400 is input with a signal indicating the system state of the first AC power system 10 and / or the second AC power system 11. The signal indicating the system state is, for example, the open / close status of a circuit breaker in the power system. The rate-of-change limiting circuit 400 stores a rate of change with respect to a preset system state, and the stored rate of change is applied according to a signal representing the system state input to the rate-of-change limiting circuit 400. . The rate of change means the rate of change of the input signal per unit time.

  According to such a configuration, the rate of change of the active power command input signal Pref can be changed in accordance with the change in the system state, and the rate of change of Pref in accordance with the system state can be made variable. It becomes possible to make the power flow control speed variable with respect to the change in the active power command input signal Pref. For example, when a specific line in the power system is opened and it is better to perform power flow control by the power flow control device at a low speed in terms of system stability, a low rate of power flow control is set by setting a small change rate. If it is better to perform power flow control at high speed, power flow control considering the system stability such as increasing the rate of change is possible. The influence on the degree can be reduced.

  FIG. 9 is a configuration diagram of the power flow controller 201 corresponding to the seventh embodiment of the present invention. The difference from the first to third embodiments or the sixth embodiment is that a fluctuation suppression circuit 401 is provided, and an output of the fluctuation suppression circuit 401 is added to the active power command input signal Pref.

  In the fluctuation suppressing circuit 401, an incomplete differential element 401a, a phase advance / delay element 401b, a gain element 401c, and a limit element 401d are connected in series. The input signal is a signal representing the passing power P of the power transmission line 20 measured and detected by the power transducer 203. In the incomplete differentiation element 401a, the direct current component of the input signal is removed, and the change in the input signal is extracted and sent to the phase advance / delay element 401b. The phase advance / delay element 401b corrects the phase advance or delay for the frequency band according to the set constant, and the gain element 401c multiplies the gain to be set. Note that the phase lead / lag compensation may utilize not only one element but also a plurality of elements. The output of the gain element 401c is limited to the range of the upper and lower limit values set by the limiter element 401d, and the output of the fluctuation suppressing circuit 401 that is the output of the limiter element 401d is added to the active power command input signal Pref.

  In the eighth embodiment, the configuration of the fluctuation suppression circuit 401 is the same as that of the seventh embodiment, and the input signal of the fluctuation suppression circuit 401 is measured by the bus in the first AC power system 10 or the second AC power system 11. It is a frequency to do.

  In the ninth embodiment, the configuration of the fluctuation suppression circuit 401 is the same as that of the seventh embodiment, and the input signal of the fluctuation suppression circuit 401 is measured by the bus in the first AC power system 10 or the second AC power system 11. Is the magnitude of the voltage to be applied.

  According to such a configuration, it is possible to detect the fluctuation of the input signal of the fluctuation suppressing circuit 401, correct the phase of the input signal by performing phase advance / lag compensation, and add it to the active power command input signal Pref. Therefore, it is possible to promote the attenuation of the input signal of the fluctuation suppressing circuit 401 while adjusting the power flow of the transmission line 20 to the power command value Pref. More specifically, in the seventh embodiment, attenuation with respect to fluctuations in the power flow of the transmission line 20 can be promoted, and in the eighth embodiment, attenuation with respect to frequency fluctuations in the first AC power system 10 or the second AC power system 11. In the ninth embodiment, it is possible to promote the attenuation with respect to the voltage fluctuation measured by the bus in the first AC power system 10 or the second AC power system 11.

  Therefore, it is possible to control the power flow fluctuation, the frequency fluctuation, or the voltage fluctuation quickly while keeping the power flow of the transmission line constant.

  FIG. 10 is a configuration diagram of a power flow control device corresponding to Example 10 of the present invention. A capacitor 600 is connected to the ground from a connection bus 20b between the rotary transformer 101 and the first AC power system 10 and a connection bus 21b between the rotary transformer 101 and the second AC power system 11. . Note that the capacitor 600 connected to the connection bus 20b and the connection bus 21b may be either one.

  When the capacitor 600 is connected to one of the connection bus 20b and the connection bus 20b, the impedance −jXc of the capacitor 600 has a value having the same absolute value as the excitation impedance jXm of the rotary transformer 101, that is, “jXc = −jXm ”. When the capacitor 600 is connected to both the connection bus 20b and the connection bus 21b, each capacitor impedance jXc is set to “jXc = −jXm / 2”.

  According to such a configuration, it is possible to cancel the voltage drop due to the delayed reactive power consumption of the excitation impedance of the rotary transformer 101 by generating the reactive power due to the capacitor impedance, and by the installation of the rotary transformer 101. It is possible to prevent a voltage drop.

  Although the case where a capacitor is connected from the bus to the ground has been described here, a capacitor may be connected between each of the three-phase buses. When an impedance is connected between the three-phase lines, a capacitor having an impedance value that is three times the capacitor impedance value connected between the grounds may be connected between the three-phase lines.

  FIG. 11 is a configuration diagram of the rotary transformer 101 corresponding to the eleventh embodiment of the present invention. The difference from the description in the second embodiment shown in FIG. 2 is that the rotor 101R is only the rotor cage 103 and there is no slip ring 102. The three-phase lines RR, SR, TR from the first AC power system 10 are connected to the corresponding phases of the rotor squirrel cage part 103 via the three conducting wires 500. The rotary phase transformer 101 of the present invention rotates in both directions, but since the rotation is limited to within one rotation, even if it is connected to the rotor 101R by three conducting wires 500 having a margin in length. The rotation change of the rotor 101R is not disabled.

  According to such a configuration, since the slip ring of the rotor 101R can be omitted, maintenance is facilitated, the maintenance cycle is extended, the reliability of the power flow control device is increased, and the operation cost is reduced. It becomes possible to do.

  The power flow control device of the present invention can be used to stabilize the system regardless of the size of the power system.

1 is a configuration diagram of a power flow control device corresponding to Example 1. FIG. FIG. 3 is a configuration diagram of a power flow controller corresponding to the first embodiment. It is a block diagram of the rotary transformer of an electric power flow control apparatus. FIG. 6 is a configuration diagram of a power flow controller 201 corresponding to the second embodiment. FIG. 6 is a configuration diagram of a power flow controller 201 corresponding to the third embodiment. It is a block diagram of the tidal current controller 201 corresponding to Example 4. FIG. 10 is a configuration diagram of a control device 200 corresponding to a fifth embodiment. FIG. 10 is a configuration diagram of a power flow controller 201 corresponding to a sixth embodiment. FIG. 10 is a configuration diagram of a power flow controller 201 corresponding to Examples 7 to 9. FIG. 10 is a configuration diagram of a power flow control device corresponding to Example 10. It is a block diagram of the power flow control apparatus corresponding to Example 11.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... 1st alternating current power system, 11 ... 2nd alternating current power system, 101 ... Rotary transformer, 101R ... Rotor, 101S ... Stator, 102 ... Slip ring, 103 ... Rotor cage shape part, 20 ( RR, SR, TR) ... transmission line, 21 (RS, SS, TS) ... transmission line, 30 ... drive motor, 31 ... stopper device, 32 ... speed detector, 33 ... angle detector, 200 ... control device, 201 DESCRIPTION OF SYMBOLS ... Power flow controller, 202 ... Torque controller, 203 ... Power transducer, 301 ... Power command limiter, 302a, 302b, 302c, 302d ... Phase difference calculator, 304 ... PI control circuit, 304a ... Proportional element, 304b ... Integration element , 304c ... Limiter element, 305 ... Rotational speed command limiter, 306 ... Rotation angle soft limiter, 307 ... Rotation angle conversion gain, 308 ... Proportional differential control circuit, 400 ... Change rate control Circuit, 401 ... variation suppressor, 401a ... inexact differential element, 401b ... phase lead-lag element, 401c ... gain element 401d ... Limit element 500 ... power line, 600 ... capacitor

Claims (11)

A rotary transformer having a rotor and a stator, wherein the rotor is coupled to a first AC power system, and wherein the stator is coupled to a second AC power system;
A stopper device for limiting a rotation angle range of the rotor;
A drive motor for driving the rotor;
A power flow controller that compares a predetermined passing power with a current passing power of the rotary transformer and calculates an angular velocity command value of the rotor;
A torque controller that adjusts the output torque of the drive motor from the angular velocity command value and the angular velocity of the rotor;
The current passing electric power can be controlled to the predetermined passing electric power by adjusting a rotation angle of the rotor with respect to the stator in a state in which the rotation is limited to a predetermined rotation angle range by the stopper device. Power flow control device.   The power flow controller includes a magnitude of a voltage of a first bus that couples the rotor and the first AC power system, and a magnitude of a voltage of a second bus that couples the stator and the second AC power system. And the voltage phase difference between the first bus and the second bus corresponding to the predetermined passing power and the voltage phase difference between the first bus and the second bus corresponding to the current passing power. The power flow control device according to claim 1, wherein a voltage phase difference deviation is calculated, and an angular velocity command value of the rotor is calculated from the voltage phase difference deviation.   The power flow controller includes a magnitude of a voltage of a first bus that couples the rotor and the first AC power system, and a magnitude of a voltage of a second bus that couples the stator and the second AC power system. A reactive power value passing through the first bus or the second bus, and a voltage phase difference between the first bus and the second bus corresponding to the predetermined passing power and corresponding to the current passing power The voltage phase difference deviation between the voltage phase difference between the first bus and the second bus is calculated, and the angular velocity command value of the rotor is calculated from the voltage phase difference deviation. Power flow control device.   The power flow controller takes in a rotation angle of the rotor, calculates a predetermined rotation angle of the rotor corresponding to the predetermined passing power using the rotation angle, and sets the predetermined rotation angle within a set angle range. 4. An angular velocity command value for the rotor is calculated from an output of the rotation angle soft limiter and a rotation angle of the rotor, the rotation angle soft limiter outputting a limited rotation angle. The power flow control device according to claim 1.   The tidal current controller takes in the rotation angle of the rotor, adds a value calculated through a proportional element and / or a differential element to the rotation angle, and adds the angular speed command value to a predetermined angular speed command value. The power flow control device according to any one of claims 1 to 4, wherein the power flow control device outputs the signal while limiting the value within a range.   A command change rate limiting circuit that changes the change rate limit of the predetermined passing power according to the system state of the AC power system to which the rotary transformer is coupled, and outputs the predetermined passing power within the range of the change rate limit The power flow control device according to claim 1, comprising:   The value calculated through the gain element, the phase compensation element, and the incomplete differential element is added to the current passing power of the rotary transformer to the predetermined passing power. The power flow control device according to any one of the above.   Taking in the frequency of the first AC power system or the second AC power system to which the rotary transformer is coupled, a value calculated through a gain element, a phase compensation element, and an incomplete differential element, The power flow control device according to claim 1, wherein the power flow control device adds to the predetermined passing power.   Takes in the magnitude of the bus voltage of the first AC power system or the second AC power system to which the rotary transformer is coupled, and calculates it through a gain element, a phase compensation element, and an incomplete differential element The power flow control device according to claim 1, wherein the calculated value is added to the predetermined passing power.   A capacitor is connected between the coupling bus of the rotor and the first AC power system or between the coupling bus of the stator and the second AC power system and the ground or a three-phase line. The power flow control device according to any one of 1 to 9.   The power flow control device according to any one of claims 1 to 10, wherein the rotor winding and the first AC power system are connected by a conductive wire having a margin in length.

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