A control method and device for an AC controllable self - recovering energy dissipation device

Abstract

The present invention discloses a control method and device for an AC controllable self - recovering energy dissipation device, including: obtaining the energy values absorbed by the controllable self - recovering energy dissipation device at a second preset time interval within a first preset time and accumulating them to obtain an accumulated energy value; determining whether the accumulated energy value is less than a first preset energy value; if so, obtaining a new energy value at the second preset time interval, replacing the earliest obtained energy value within the first preset time with the newly obtained energy value according to the first - in - first - out principle, and calculating a new accumulated energy value; if not, directly locking, and clearing the energy values absorbed by the controllable self - recovering energy dissipation device after the locking ends. By obtaining the single - time and accumulated energy values and comparing them with the preset energy value, it is determined whether to directly lock or replace and superimpose the energy values within the preset time. On the basis of considering the cooling requirements of the arrester, the safe and stable operation of the device is ensured, and the system fault crossing is completed on the basis of utilizing the energy consumption capacity of the equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment control, and particularly relates to a control method and device for an AC controllable self - restoring energy dissipation device. Background Art

[0002] The Zhalute - Qingzhou ±800kV DC transmission project has a DC line length of 1234 km, one double - pole DC line, and two 12 - pulse converters in series for each pole. The rated voltage is ±800 kV, the DC transmission capacity is 10000 MW, the DC rated current is 6250 A, and it was put into operation in bipolar mode in 2017. The Zhalute converter station usually operates as a rectifier station, and the Qingzhou converter station usually operates as an inverter station. The Zhalute - Qingzhou ±800kV DC transmission project is a bipolar DC system, in which the converter valve equipment and the bipolar DC control and protection system of the Zhalute station are both supplied by Xuji Electric Co., Ltd. Both the sending - end and receiving - end systems include two complete monopoles, and each complete monopole is composed of two 12 - pulse converter units in series. The converter transformer adopts a single - phase double - winding type, and three 50mH dry - type smoothing reactors are arranged on each of the pole lines and neutral buses of the sending - end and receiving - end converter stations.

[0003] The current actual transmission limit of the Zhalute - Qingzhou ±800kV DC transmission project is 6500 MW, and the main limiting factors are the transient over - voltage of the sending - end converter bus and the static stability limit of the long - distance south line of the receiving - end UHV. According to the calculation conclusion of the national dispatching center, after three thermal power units are put into production in the near area of Zhalute at the sending - end and four thermal power units are put into production in the near area of the Changzhi UHV station at the receiving - end in 2021, the transmission limit of the Zhalute - Qingzhou DC will be increased to 7200 MW, and there is still a space of about 3000 MW.

[0004] When a bipolar DC fault (bipolar commutation failure, bipolar blocking, bipolar line restart) occurs in the high - power mode, a large amount of excess reactive power is generated by the AC system and AC filters during the DC power interruption, causing a transient over - voltage exceeding the system control level (1.3 p.u.) at the Zhalute converter station, which is the main problem restricting DC power. Installing an AC controllable self - restoring energy dissipation device on the AC bus of the Zhalute station can effectively solve the system over - voltage problem.

[0005] The controllable self - restoring energy dissipation device is installed between the AC I bus and AC II bus of the Zhalute station. When a fault occurs in the system, the control system issues a closing command to the energy dissipation device. After receiving the closing command, the control switch conducts, and the controlled element of the lightning arrester is short - circuited, reducing the overall protection level of the lightning arrester and deeply suppressing the system over - voltage. When the fault disappears and the system parameters return to the normal range, the control switch opens, and the controllable self - restoring energy dissipation device resumes normal operation. Summary of the Invention

[0006] The object of the embodiment of the present invention is to provide a control method and device for an AC controllable self - recovering energy dissipation device. By obtaining the energy values obtained singly and cumulatively and comparing them with a preset energy value, it is determined whether to directly lock or perform replacement and superposition of the energy values within a preset time. On the basis of considering the cooling requirements of the lightning arrester, the safe and stable operation of the device is ensured, and the system fault crossing is completed on the basis of maximizing the energy consumption capacity of the equipment.

[0007] To solve the above - mentioned technical problems, a first aspect of the embodiment of the present invention provides a control method for an AC controllable self - recovering energy dissipation device, including the following steps:

[0008] Obtain and accumulate the energy values absorbed by the controllable self - recovering energy dissipation device at a second preset time interval within a first preset time to obtain an accumulated energy value;

[0009] Judge whether the accumulated energy value is less than a first preset energy value;

[0010] If so, obtain a new energy value at the second preset time interval, replace the earliest - obtained energy value within the first preset time with the newly - obtained energy value according to the first - in - first - out principle, and calculate a new accumulated energy value;

[0011] If not, directly lock and clear the energy values absorbed by the controllable self - recovering energy dissipation device after the locking ends.

[0012] Further, before obtaining and accumulating the energy values absorbed by the controllable self - recovering energy dissipation device at a second preset time interval within a first preset time, it further includes:

[0013] At the first preset time, obtain several energy values at the second preset time interval and accumulate them.

[0014] Further, after directly locking and clearing the energy values absorbed by the controllable self - recovering energy dissipation device after the locking ends, it further includes:

[0015] Obtain the locking time, and the locking time is inversely proportional to the heat dissipation performance of the lightning arrester.

[0016] Further, after obtaining the energy values absorbed by the controllable self - recovering energy dissipation device at a second preset time interval within a first preset time, it further includes:

[0017] When the singly - obtained energy value is greater than the first preset energy value, directly lock.

[0018] Further, after directly locking and clearing the energy values absorbed by the controllable self - recovering energy dissipation device after the locking ends, it further includes:

[0019] After the accumulated energy value is cleared, when a new input instruction is received, the timing of the first preset time is restarted.

[0020] The second aspect of the embodiments of the present invention provides a control device for an AC controllable self - recovering energy - dissipating device, including:

[0021] A data acquisition module, which is used to acquire the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval within a first preset time and accumulate them to obtain an accumulated energy value;

[0022] A data judgment module, which is used to judge whether the accumulated energy value is less than a first preset energy value;

[0023] A control module, which is used to acquire new energy values at the second preset time interval when the accumulated energy value is less than the first preset energy value, and replace the earliest - acquired energy value within the first preset time with the newly - acquired energy value according to the first - in - first - out principle, and calculate a new accumulated energy value;

[0024] The control module is further used to directly lock when the accumulated energy value is greater than or equal to the first preset energy value, and clear the energy values absorbed by the controllable self - recovering energy - dissipating device after the locking ends.

[0025] Further, the data acquisition module includes: a data accumulation unit;

[0026] The data accumulation unit is used to acquire a plurality of energy values at the second preset time interval within the first preset time and accumulate them.

[0027] Further, the control device for the AC controllable self - recovering energy - dissipating device further includes:

[0028] A locking - time calculation module, which is used to acquire a locking time, and the locking time is inversely proportional to the heat - dissipation performance of the lightning arrester.

[0029] Further, when the energy value acquired by the data acquisition module once is greater than the first preset energy value, the control module directly locks.

[0030] Further, the control module is further used to restart the timing of the first preset time when a new input instruction is received after the accumulated energy value is cleared.

[0031] The above - mentioned technical solutions of the embodiments of the present invention have the following beneficial technical effects:

[0032] By obtaining the energy values obtained singly and cumulatively, comparing them with the preset energy value to determine whether to directly lock or replace and superimpose the energy values within a preset time, on the basis of considering the cooling requirements of the arrester, the safe and stable operation of the device is ensured, and the system fault crossing is completed on the basis of maximizing the energy consumption capacity of the equipment. Description of the Drawings

[0033] Figure 1 It is a process diagram of the control method of the AC controllable self - recovering energy - dissipating device provided by the embodiment of the present invention;

[0034] Figure 2 It is a logic diagram of the control method of the AC controllable self - recovering energy - dissipating device provided by the embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the controllable self - recovering energy - dissipating device (single - phase) provided by the embodiment of the present invention;

[0036] Figure 4 It is a schematic diagram of the implementation principle of the first - in - first - out algorithm provided by the embodiment of the present invention. Detailed Embodiments

[0037] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the detailed embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the descriptions of well - known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0038] Please refer to Figure 1 、 Figure 2 and Figure 3 The first aspect of the embodiment of the present invention provides a control method for an AC controllable self - recovering energy - dissipating device, including the following steps:

[0039] Step S100, within a first preset time, obtain the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval and accumulate them to obtain an accumulated energy value.

[0040] Step S200, determine whether the accumulated energy value is less than a first preset energy value.

[0041] Step S300, if so, obtain a new energy value at the second preset time interval, and replace the earliest - obtained energy value within the first preset time with the newly - obtained energy value according to the first - in - first - out principle, and calculate the new accumulated energy value.

[0042] Step S400, if not, directly lock, and after the locking ends, clear the energy values absorbed by the controllable self - recovering energy - dissipating device.

[0043] In the above solution, the controllable self - recovering energy - dissipating device consists of a controllable part and an uncontrollable part. The controllable part is composed of a trigger switch and a bypass switch. When a system fault occurs, the controllable part is short - circuited to put the uncontrollable part of the arrester into operation. When the fault disappears, the controllable self - recovering energy - dissipating device resumes normal operation.

[0044] The locking logic control after the controllable self - recovering energy - dissipating device absorbs energy is divided into two segments. When the absorbed energy is greater than or equal to pMJ, it is directly locked. When the absorbed energy is less than pMJ, it has the ability to be put into operation at any time. However, considering energy accumulation, a method is proposed. Starting from the first input, the absorbed energy is stored in a fixed storage area within a period of time t. A set of values is stored at fixed time intervals Δt. If there is a re - input instruction during this period, the accumulated absorbed energy value is calculated. If the accumulated energy value is greater than or equal to pMJ, it is directly locked. If the energy value is less than pMJ, after time t arrives, at intervals of Δt, according to the "first - in - first - out" algorithm, the advanced array is removed, and the loop is executed until the accumulated energy value is greater than or equal to pMJ and is directly locked. When the locking ends, the absorbed energy value is cleared. When a new input instruction is received again, a new timing logic starts.

[0045] By controlling the opening and closing of the switch, the input and output of the uncontrollable part of the arrester are realized, and the input strategy of the arrester is controlled. On the premise of ensuring the safety of the equipment, the system transient over - voltage is suppressed as much as possible, the anti - disturbance ability of the system is provided, and the safe and stable operation of the power grid is guaranteed.

[0046] By controlling the trigger switch and closing the bypass switch to short - circuit the controllable part of the arrester, the operating voltage of the controllable self - recovering energy - dissipating device is reduced, so that the uncontrollable part of the arrester reaches the operating voltage and absorbs the system transient over - voltage.

[0047] When the system fault is eliminated, the DC control system completes the elimination of the input instruction, and the output instruction is valid. At this time, the controllable self - recovering energy - dissipating device opens the bypass switch and the trigger switch, the controllable part of the arrester is connected, and the operating voltage of the controllable self - recovering energy - dissipating device increases.

[0048] Further, in step S100, before obtaining and accumulating the energy value absorbed by the controllable self - recovering energy - dissipating device at the second preset time interval within the first preset time, it further includes:

[0049] Step S110, at the first preset time, obtain several energy values at the second preset time interval and accumulate them.

[0050] Further, in step S400, after directly locking and clearing the energy value absorbed by the controllable self - recovering energy - dissipating device after the locking ends, it further includes:

[0051] Step S410, obtain the locking time, and the locking time is inversely proportional to the heat dissipation performance of the arrester.

[0052] Specifically, after obtaining the energy value absorbed by the controllable self - recovering energy dissipation device at the second preset time interval within the first preset time, the following steps are further included:

[0053] Step S120: When the energy value obtained in a single acquisition is greater than the first preset energy value, directly lock out.

[0054] Further, after step S400: directly lock out and clear the energy value absorbed by the controllable self - recovering energy dissipation device after the lock - out ends, the following steps are further included:

[0055] Step S500: After clearing the accumulated energy value, when receiving a new input command, restart the timing of the first preset time.

[0056] In a specific implementation manner of the embodiment of the present invention, after the power - on of the control system of the controllable self - recovering energy dissipation device, through the self - check status, it is detected whether the allow - input is valid. If it is invalid, no input logic is executed; if it is valid, it is detected whether the input command issued by the DC control system is valid. If it is invalid, no input logic is executed. If it is valid, the first input is performed. After the input is completed, the absorbed energy m1 is calculated, and it is judged whether m 1 is greater than or equal to 60 MJ (the maximum absorption energy of the device 200 MJ - the single - time maximum absorption energy 140 MJ). If it is greater, direct lock - out is performed, and the lock - out time is shown in Table 1, the lock - out time table when the absorbed energy of the controllable self - recovering energy dissipation device is greater than or equal to 60 MJ. Due to the non - linearity of the arrester cooling, discrete processing is performed. 60 MJ is used as a critical point, and a separate cooling time is set. After that, a cooling time corresponds to every 10 MJ, and the larger value is used for cooling.

[0057] When m1 is less than 60 MJ, the absorbed energy is stored in a fixed storage area within 3 h. Considering the on - off time each time, the fixed time Δt is set to 5 min, that is, a set of values is stored every 5 min, and m 1 is stored in the first array; and the energy of each time is accumulated. If there is no input, the energy m i = 0; if the accumulated energy is greater than or equal to 60 MJ, direct lock - out processing corresponding to the time is performed, and the lock - out time is shown in Table 1. Wait for the cooling time to be cleared, and then enter the judgment logic again; if the accumulated energy is still less than 60 MJ, it is sequentially stored in the array. There are a total of 36 arrays. When the time reaches 3 h, the array is full, and the "first - in - first - out" algorithm is enabled.

[0058] Table 1 Lock - out time table when the absorbed energy of the controllable self - recovering energy dissipation device is greater than or equal to 60 MJ

[0059]

[0060] As Figure 4 shown, after the control system of the controllable self - restoring energy dissipation device is powered on, if it detects that the "first - in - first - out" algorithm is enabled effectively, it iterates a set of data every 5 minutes, that is, at the falling edge of the 5 - minute timing, the value of m 2 is assigned to m 1 ; that is, the value of m 3 is assigned to m 2 ;... the value of m 36 is assigned to m 35 ; the latest value of m i is assigned to m 36 ; until the sum (m 1 +m 2 +... +m 36 ) is greater than 60 MJ, otherwise it keeps executing. The "first - in - first - out" storage point table is shown in Table 2.

[0061] Table 2 First - in - first - out storage point table

[0062]

[0063]

[0064] Through the above - mentioned implementation manners, the lightning arrester can be utilized to the maximum extent, the transient over - voltage can be absorbed, and support can be provided for the safe and stable operation of the power grid system.

[0065] Correspondingly, the second aspect of the embodiment of the present invention provides a control device for an AC controllable self - restoring energy dissipation device, including:

[0066] A data acquisition module, which is used to acquire the energy values absorbed by the controllable self - restoring energy dissipation device at a second preset time interval within a first preset time and accumulate them to obtain an accumulated energy value;

[0067] A data judgment module, which is used to judge whether the accumulated energy value is less than a first preset energy value;

[0068] A control module, which is used to acquire new energy values at the second preset time interval when the accumulated energy value is less than the first preset energy value, and replace the earliest acquired energy value within the first preset time with the newly acquired energy value according to the first - in - first - out principle, and calculate a new accumulated energy value;

[0069] The control module is further used to directly lock when the accumulated energy value is greater than or equal to the first preset energy value, and clear the energy values absorbed by the controllable self - restoring energy dissipation device after the locking ends.

[0070] Furthermore, the data acquisition module includes: a data accumulation unit;

[0071] The data accumulation unit is used to acquire a plurality of energy values at the second preset time interval within the first preset time and accumulate them.

[0072] Furthermore, the control device of the AC controllable self - recovering energy - dissipating device further includes:

[0073] A blocking time calculation module, which is used to obtain the blocking time, and the blocking time is inversely proportional to the heat dissipation performance of the lightning arrester.

[0074] Furthermore, when the energy value obtained by the data acquisition module in a single time is greater than the first preset energy value, the control module directly blocks.

[0075] Furthermore, the control module is further used to restart the timing of the first preset time when receiving a new input instruction after clearing the accumulated energy value.

[0076] The embodiments of the present invention aim to protect an AC controllable self - recovering energy - dissipating device control method and device, having the following effects:

[0077] By obtaining the energy values obtained singly and accumulatively, comparing them with the preset energy values to determine whether to directly block or perform replacement and superposition of the energy values within a preset time, on the basis of considering the cooling requirements of the lightning arrester, the safe and stable operation of the device is ensured, and the system fault crossing is completed on the basis of maximizing the energy consumption capacity of the equipment.

[0078] It should be understood that the above - mentioned specific embodiments of the present invention are only used for exemplary illustration or explanation of the principle of the present invention, and do not constitute a limitation to the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention shall be included within the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modification examples falling within the scope and boundary of the appended claims, or equivalent forms of such scope and boundary.

Claims

1. A control method for an AC controllable self - recovering energy - dissipating device, characterized in that, it includes the following steps: Obtain the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval within a first preset time and accumulate them to obtain an accumulated energy value; Judge whether the accumulated energy value is less than a first preset energy value; If so, obtain a new one of the energy values at the second preset time interval, and replace the earliest - obtained energy value within the first preset time with the newly - obtained energy value according to the first - in - first - out principle, and calculate a new accumulated energy value; If not, directly lock it, and after the locking ends, clear the energy values absorbed by the controllable self - recovering energy - dissipating device; After directly locking and clearing the energy values absorbed by the controllable self - recovering energy - dissipating device after the locking ends, it further includes: Obtain the locking time, and the locking time is inversely proportional to the heat - dissipation performance of the lightning arrester.

2. The control method for an AC controllable self - recovering energy - dissipating device according to claim 1, characterized in that, before obtaining the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval within a first preset time and accumulating them, it further includes: At the first preset time, obtain several of the energy values at the second preset time interval and accumulate them.

3. The control method for an AC controllable self - recovering energy - dissipating device according to claim 1, characterized in that, after obtaining the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval within a first preset time, it further includes: When the energy value obtained each time is greater than the first preset energy value, directly lock it.

4. The control method for an AC controllable self - recovering energy - dissipating device according to claim 1, characterized in that, after directly locking and clearing the energy values absorbed by the controllable self - recovering energy - dissipating device after the locking ends, it further includes: After clearing the accumulated energy value, when receiving a new input command, restart the timing of the first preset time.

5. A control device for an AC controllable self - recovering energy - dissipating device, characterized in that, it includes: A data acquisition module, which is used to obtain the energy values absorbed by the controllable self - recovering energy - dissipating device at a second preset time interval within a first preset time and accumulate them to obtain an accumulated energy value; A data judgment module, which is used to judge whether the accumulated energy value is less than a first preset energy value; A control module, which is used to obtain a new one of the energy values at the second preset time interval when the accumulated energy value is less than the first preset energy value, and replace the earliest - obtained energy value within the first preset time with the newly - obtained energy value according to the first - in - first - out principle, and calculate a new accumulated energy value; The control module is further used to directly lock it when the accumulated energy value is greater than or equal to the first preset energy value, and after the locking ends, clear the energy values absorbed by the controllable self - recovering energy - dissipating device; It further includes: A locking - time calculation module, which is used to obtain the locking time, and the locking time is inversely proportional to the heat - dissipation performance of the lightning arrester.

6. The control device for an AC controllable self - recovering energy - dissipating device according to claim 5, characterized in that, The data acquisition module includes: a data accumulation unit; The data accumulation unit is configured to obtain a plurality of the energy values at the first preset time according to the second preset time interval, and accumulate them.

7. The control device of the alternating current controllable self - restoring energy - dissipating device according to claim 5, wherein, when the energy value obtained by the data acquisition module once is greater than the first preset energy value, the control module directly locks.

8. The control device of the alternating current controllable self - restoring energy - dissipating device according to claim 5, wherein, the control module is further configured to restart the timing of the first preset time when receiving a new input command after the accumulated energy value is cleared.

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