Temperature compensation type wide-temperature-range high-precision electric energy meter and acquisition terminal

Abstract

The invention relates to the technical field of electrical variable measurement, and particularly discloses a temperature compensation type wide-temperature-range high-precision electric energy meter and an acquisition terminal, and the electric energy meter comprises a signal reading and recording module, an application scene analysis module, an interval compensation error calculation module, a polynomial error calculation module and a subitem dynamic compensation module. The application scene analysis module is used for receiving the electric energy acquisition parameters acquired by the signal reading and recording module and allocating error processing modes according to scenes corresponding to the electric energy acquisition parameters; classification during wide temperature range compensation value measurement is set as an electric energy parameter linear temperature drift scene and an electric energy parameter nonlinear significant scene, and an internal temperature range error of an electric energy meter is subjected to approval processing in a corresponding environment to obtain a corresponding interval error debugging value or fitting error debugging value; and the approved interval error debugging value or the approved fitting error debugging value is used as a temperature compensation parameter for temperature compensation processing, so that the metering precision of the electric energy meter after temperature compensation is finally completed is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical variable measurement, and specifically to a temperature-compensated high-precision watt-hour meter and acquisition terminal with a wide temperature range. Background Art

[0002] Since the measurement accuracy of a watt-hour meter is directly affected by temperature conditions, there will be deviations in the measured values under high and low temperatures. Therefore, temperature compensation is required during measurement. Especially for applications in a wide temperature range environment, due to the different temperature change rates in different situations affected by the environment, the measurement error increases.

[0003] A Chinese patent discloses a method and system for dynamically compensating the measurement error of a segmented intelligent watt-hour meter, with the publication number CN101498741A. This technical solution uses the segmentation method to segment the power-on time, calculates the change value of the measurement error of the intelligent watt-hour meter when passing the maximum current during the power-on time, and calculates the measurement error compensation value of the intelligent watt-hour meter according to the change value of the measurement error and the power factor weight. However, when this technical solution is applied to temperature compensation in a wide temperature range, due to the large range of the wide temperature range and the rapid change between the values of each interval, this technical solution cannot quickly lock the change value according to the temperature interval, nor can it quickly fit the polynomial for the errors in the entire temperature range. Therefore, it is not stable enough when applied to a wide temperature range.

[0004] A Chinese patent discloses a method for improving the measurement accuracy of an intelligent electric meter, with the publication number CN105223416A. Its method of dividing multiple intervals according to the error data of each temperature point of the existing watt-hour meter for temperature compensation can reduce the error percentage, but this technical solution is mainly applied to linear temperature drift and cannot be applied to the environment with high-span temperature changes in a wide temperature range. Therefore, in order to ensure the applicability of temperature compensation in a wide temperature range, a temperature-compensated high-precision watt-hour meter and acquisition terminal with a wide temperature range are proposed. Summary of the Invention

[0005] In view of the problems in the prior art, the present invention provides a temperature-compensated high-precision watt-hour meter and acquisition terminal with a wide temperature range. The technical solution adopted by the present invention to solve its technical problems is: a temperature-compensated high-precision watt-hour meter and acquisition terminal with a wide temperature range, including a signal reading and recording module, and further including an application scenario analysis module, an interval compensation error calculation module, a polynomial error calculation module, and a sub-item dynamic compensation module; The application scenario analysis module is used to receive the power acquisition parameters obtained by the signal reading and recording module, and allocate error processing methods according to the scenarios corresponding to the power acquisition parameters; The interval compensation error calculation module is applied to the scenario of linear temperature drift of electric energy parameters. The interval compensation error calculation module pre-divides the error compensation amount of each temperature zone interval inside the electric energy meter, and after obtaining the electric energy parameters sent by the signal reading and recording module, the total error of the electric energy parameters is verified according to the error compensation amount of the current temperature zone interval inside the electric energy meter, thereby obtaining the interval error debugging value; The polynomial error calculation module is applied to the scenario where the electric energy parameter is nonlinearly significant, and the polynomial fitting of the full temperature range error inside the electric energy meter is performed through the sub-item dynamic compensation module, so as to obtain the fitting error debugging value; The sub-item dynamic compensation module is used to obtain the interval error debugging value or the fitting error debugging value, and then perform subsequent temperature compensation according to the corresponding error debugging value.

[0006] Preferably, the specific analysis process of the interval error debugging value is: S11. Read the linear compensation coefficient of the electric energy meter in each temperature zone from the existing database, including the temperature sensitivity coefficient and the reference offset ; S12, set the temperature parameter to K, the temperature interval separation point is , , ; S13. Substitute the error compensation coefficient into the following formula to calculate the total error under the temperature parameter K: ; In the formula, Expressed as the total error at temperature T, is the minimum value of the operating temperature range, is the maximum value of the operating temperature range; S14, after calculation, It is set as the interval error debugging value and output to the sub-item dynamic compensation module.

[0007] Preferably, the specific analysis process of the fitting error debugging value is: S21, obtain the reference error of the electric energy meter at zero temperature and zero current, and set it as ; S22. Obtain the coefficients of temperature-related items from the existing database, including the linear temperature item coefficients , Secondary temperature term coefficient , cubic temperature coefficient , Linear current term coefficient and the current cross-term coefficient ; S23, substituting the reference error obtained in S21 and the coefficient of the temperature-related term obtained in S22 into the following formula to obtain the fitting error debugging value: ; Wherein, K is the current temperature parameter and I is the load current; After S24 is calculated, It is set as the fitting error debugging value and output to the sub-item dynamic compensation module.

[0008] Preferably, a lag error elimination parameter module is further provided between the sub-item dynamic compensation module and the polynomial error calculation module. The lag error elimination parameter module obtains the internal temperature rise and fall rate of the electric energy meter, measures the dynamic compensation value, then analyzes and obtains the quadratic fitting error debugging value according to the dynamic compensation value, and finally eliminates the lag effect generated by the rapid temperature change during the process of obtaining the fitting error debugging value by the polynomial error calculation module through the obtained quadratic fitting error debugging value.

[0009] Preferably, the steps for the lag error elimination parameter module to obtain the dynamic compensation value are as follows: S31. Calculate the current internal temperature rise and fall rate of the electric energy meter according to the temperature data monitored inside the electric energy meter; S32. Substitute the internal temperature rise rate of the electric energy meter into the following formula for dynamic compensation to obtain the dynamic compensation value: ; In the above formula, represents the dynamic compensation value; represents the temperature change rate.

[0010] Preferably, the steps for the lag error elimination parameter module to calculate the quadratic fitting error debugging value are as follows: S41. Substitute the dynamic compensation value for the original linear temperature term coefficient , quadratic temperature term coefficient , cubic temperature term coefficient into the fitting error debugging value calculation formula to obtain the compensated quadratic fitting error debugging value: ; After S42 is calculated, is set as the quadratic fitting error debugging value and output to the sub-item dynamic compensation module.

[0011] Preferably, the signal reading and recording module includes a signal transmission unit, a ROM memory, and a signal conditioning circuit. The signal transmission unit is used to obtain the electric energy meter monitoring data and upload it to the ROM memory for short-term storage after obtaining it. The signal conditioning circuit is used to amplify and filter the noise-containing signal output by the signal transmission unit.

[0012] Preferably, the sub-item dynamic compensation module is connected to the external data processing terminal signal, and the sub-item dynamic compensation module is used to send the debugging value obtained by the interval compensation error calculation module or the polynomial error calculation module to the external data processing terminal, and the external data processing terminal performs compensation adjustment of the power collection parameters.

[0013] Preferably, the temperature-compensated wide temperature range high-precision electric energy meter comprises: The electric energy metering module is used to obtain the changes in current and voltage at the end to be detected and calculate the electric energy usage; Wide temperature power supply module, used for power supply during measurement in a wide temperature range; A multi-point temperature sensor is arranged at a local position of the PCB and is used for checking the temperature at a local position of the PCB, wherein the local position of the PCB includes a metering chip position, a current sampling resistor position, and a voltage divider network position; The display module is used to display the specific parameters obtained by the electric energy metering module and the multi-point temperature sensor.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting an application scenario analysis module, the classification during measurement of the wide temperature range compensation value is set as a scenario of linear temperature drift of electric energy parameters and a scenario of significant nonlinearity of electric energy parameters; by verifying the internal temperature zone error of the electric energy meter under the corresponding environment, the corresponding interval error debugging value or fitting error debugging value is obtained, and then the verified interval error debugging value or fitting error debugging value is used as a temperature compensation parameter for temperature compensation processing, thereby improving the metering accuracy of the electric energy meter after the temperature compensation is finally completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0016] Figure 1 This is a composition diagram of the temperature compensation wide temperature range high precision data acquisition terminal of the present invention; Figure 2 This is a flow chart of the use of the temperature compensation wide temperature range high precision acquisition terminal of the present invention; Figure 3 It is a structural schematic diagram of the temperature-compensated wide-temperature-range high-precision electric energy collection meter of the present invention. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0018] Example 1 like Figures 1-3As shown, the temperature-compensated wide-temperature-range high-precision electric energy meter and acquisition terminal of the present invention include a signal reading and recording module, an application scenario analysis module, an interval compensation error calculation module, a polynomial error calculation module, and a sub-item dynamic compensation module; The application scenario analysis module is used to receive the electric energy collection parameters obtained by the signal reading module, and allocate the error processing method according to the scene corresponding to the electric energy collection parameters; wherein, the specific method of corresponding scene allocation is to monitor whether the temperature inside the electric energy meter shows a linear temperature drift. When it shows a linear temperature drift, it is allocated to the interval compensation error calculation module for error processing through the application scenario analysis module. When it shows a nonlinear state, it is allocated to the polynomial error calculation module for error processing. The corresponding effect of error processing is ensured by the dual-zone setting.

[0019] The interval compensation error calculation module is applied to the scenario of linear temperature drift of electric energy parameters. The interval compensation error calculation module pre-divides the error compensation amount of each temperature zone inside the electric energy meter, and after obtaining the electric energy parameters sent by the signal reading and recording module, the total error of the electric energy parameters is verified according to the error compensation amount of the current temperature zone inside the electric energy meter, and then the interval error debugging value is obtained.

[0020] The polynomial error calculation module is applied to scenarios with significant nonlinearity of electric energy parameters. The polynomial fitting of the error in the entire temperature range of the electric energy meter is performed through the sub-item dynamic compensation module to obtain the fitting error debugging value.

[0021] The sub-item dynamic compensation module is used to obtain the interval error debugging value or the fitting error debugging value, and then perform subsequent temperature compensation according to the corresponding error debugging value.

[0022] In an optional implementation of this embodiment, the specific analysis process of the interval error debugging value is: S11. Read the linear compensation coefficient of the electric energy meter in each temperature zone from the existing database, including the temperature sensitivity coefficient and the reference offset ; S12, set the temperature parameter to K, the temperature interval separation point is , , ; S13. Substitute the error compensation coefficient into the following formula to calculate the total error under the temperature parameter K: ; In the formula, Expressed as the total error at temperature T, is the minimum value of the operating temperature range, It is the maximum value of the operating temperature range.

[0023] S14, after calculation, Set it to the interval error debugging value and output it to the itemized dynamic compensation module.

[0024] In an alternative implementation of this embodiment, the specific analysis process of the fitting error debugging value is as follows: S21. Obtain the reference error of the watt-hour meter at zero temperature and zero current, and set it as ; S22. Obtain the coefficients of the temperature-related terms from the existing database, including the linear temperature term coefficient , the quadratic temperature term coefficient , the cubic temperature term coefficient , the linear current term coefficient , and the current cross-term coefficient ; S23. Substitute the reference error obtained in S21 and the coefficients of the temperature-related terms obtained in S22 into the following formula to obtain the fitting error debugging value: ; In the formula, K is the current temperature parameter, and I is the load current; After calculation, Set it as the fitting error debugging value and output it to the itemized dynamic compensation module.

[0025] The physical meanings and specific acquisition methods of the coefficients proposed in the above steps are shown in Table 1 below: Table 1 Physical meanings and specific acquisition methods of the proposed coefficients

[0026] Among them, is the temperature linear drift coefficient, which appears because the resistance value of the sampling resistor drifts linearly with temperature. is the temperature nonlinear drift coefficient, which appears because of the nonlinear temperature drift of semiconductor components in the voltmeter. The quadratic correction coefficient at extreme temperatures, which appears because of the complex nonlinear drift at extreme temperatures. is the current linear influence coefficient, which appears because the magnetic core saturation characteristic of the current transformer (CT) causes different error trends for small currents and large currents. is the interaction influence coefficient of temperature and current, which appears because of the self-heating effect of the current sampling resistor (i.e., the greater the current, the more significant the temperature rise, and it is superimposed with the external temperature). The above coefficients can all be monitored and obtained through the existing watt-hour metering module.

[0027] In this embodiment, a specific analysis example of the fitting error debugging value is proposed: When the error of the electricity meter exceeds the standard (+0.2%) at high temperature (75°C) and high current (6.5A) and compensation is required, substitute the above coefficients into the fitting error debugging value calculation formula: 。

[0028] After that, start the compensation action, substitute into the following formula to adjust the gain coefficient, that is, the gain coefficient = 1 / (1 + 0.4235%) ≈ 0.7024, to offset the positive error.

[0029] In this embodiment, it should be noted that the secondary correction term at extreme temperatures was not substituted and applied in the above steps because within the current temperature range (30 - 75°C), the influence of the secondary correction term on the calculation result can be ignored. The signal recording module includes a signal transmission unit, a ROM memory, and a signal conditioning circuit. The signal transmission unit is used to obtain the monitoring data of the electricity meter and upload it to the ROM memory for short-term storage after acquisition. The signal conditioning circuit is used to amplify and filter the noisy signal output by the signal transmission unit.

[0030] The sub-item dynamic compensation module is signal-connected to an external data processing terminal. The sub-item dynamic compensation module is used to send the debugging value obtained by the interval compensation error calculation module or the polynomial error calculation module to the external data processing terminal, and the external data processing terminal performs compensation adjustment on the electricity collection parameters.

[0031] In this embodiment, after obtaining the gain coefficient, immediately send the gain coefficient debugging value to the external data processing terminal, and the external data processing terminal performs subsequent compensation adjustment to offset the positive error.

[0032] The temperature compensation type wide-temperature zone high-precision electricity meter includes: An electric energy metering module, which is used to obtain the changes in current and voltage at the end to be detected and calculate the electricity usage; select an electric energy metering chip with the model ADE9153B.

[0033] A wide-temperature power supply module, which is used for power supply during wide-temperature zone measurement; specifically select an isolated DC / DC module power supply, which is suitable for power supply operations in the wide-temperature zone.

[0034] Multiple temperature sensors are arranged at local positions on the PCB. Among them, the multiple temperature sensors are used for temperature inspection of local positions on the PCB. The local positions on the PCB include the positions of the metering chip, the current sampling resistor, and the voltage divider network position; the local positions on the PCB are also the key positions on the PCB. By arranging digital temperature sensors at the key positions on the PCB, the temperature sensors are physically close to the key components to ensure that the temperature data truly reflects the component state, and then monitor the local temperature gradient of the PCB.

[0035] A display module for displaying the specific parameters obtained by the electric energy metering module and the multi-point temperature sensor.

[0036] Embodiment 2 In this embodiment, the same parts as those in Embodiment 1 will not be described again, and the differences from Embodiment 1 are that a hysteresis error eliminating parameter module is further provided between the itemized dynamic compensation module and the polynomial error calculation module. The hysteresis error eliminating parameter module obtains the temperature rise and fall rate inside the electric energy meter, measures the dynamic compensation value, then analyzes and obtains the quadratic fitting error debugging value according to the dynamic compensation value, and finally eliminates the hysteresis influence generated by the rapid temperature change during the process of the polynomial error calculation module obtaining the fitting error debugging value through the obtained quadratic fitting error debugging value.

[0037] In an alternative implementation manner of this embodiment, the specific analysis process of the conventional fitting error debugging value is as follows: S21. Obtain the reference error of the electric energy meter at zero temperature and zero current, and set it as ; S22. Obtain the coefficients of the temperature-related terms from the existing database, including the linear temperature term coefficient , the quadratic temperature term coefficient , the cubic temperature term coefficient , the linear current term coefficient , and the current cross-term coefficient ; S23. Substitute the reference error obtained in S21 and the coefficients of the temperature-related terms obtained in S22 into the following formula to obtain the fitting error debugging value: ; In the formula, K is the current temperature parameter, and I is the load current; S24. After calculation, is set as the fitting error debugging value and output to the itemized dynamic compensation module.

[0038] In this embodiment, when performing the analysis of the conventional fitting error debugging value, if the temperature rise and fall rate inside the electric energy meter obtained by the hysteresis error eliminating parameter module exceeds the set threshold, in order to avoid the hysteresis influence caused by the rapid temperature change, that is, start to obtain the temperature rise and fall rate inside the electric energy meter through the hysteresis error eliminating parameter module, measure the dynamic compensation value, then analyze and obtain the quadratic fitting error debugging value according to the dynamic compensation value, and the quadratic fitting error debugging value obtained by the hysteresis error eliminating parameter module eliminates the hysteresis influence generated by the rapid temperature change during the process of the polynomial error calculation module obtaining the fitting error debugging value.

[0039] In this embodiment, the steps for the hysteresis error eliminating parameter module to obtain the dynamic compensation value are as follows: S31. Calculate the current temperature rise and fall rate inside the electricity meter based on the temperature data monitored inside the electricity meter; S32. For the hysteresis problem caused by rapid temperature changes, introduce the temperature change rate, and substitute the temperature rise rate inside the electricity meter into the following formula for dynamic compensation to obtain the dynamic compensation value: ; In the above formula, represents the dynamic compensation value; represents the temperature change rate.

[0040] In this embodiment, the steps for the hysteresis error cancellation parameter module to calculate the quadratic fitting error debugging value are as follows: S41. Substitute the dynamic compensation value for the original linear temperature term coefficient , quadratic temperature term coefficient , cubic temperature term coefficient into the fitting error debugging value calculation formula to obtain the compensated quadratic fitting error debugging value: ; S42. After calculation, set as the quadratic fitting error debugging value and output it to the sub-item dynamic compensation module.

[0041] S43. After obtaining the gain coefficient, send the gain coefficient debugging value to the external data processing terminal, and the external data processing terminal performs subsequent compensation adjustments to cancel the positive error.

[0042] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. Temperature-compensated wide-temperature-range high-precision electric energy acquisition terminal, including a signal reading and recording module, characterized in that: It also includes an application scenario analysis module, an interval compensation error calculation module, a polynomial error calculation module, and a sub-item dynamic compensation module; The application scenario analysis module is used to receive the power collection parameters obtained by the signal reading and recording module, and allocate an error processing method according to the scenario corresponding to the power collection parameters; The interval compensation error calculation module is applied to the scenario of linear temperature drift of electric energy parameters. The interval compensation error calculation module pre-divides the error compensation amount of each temperature zone interval inside the electric energy meter, and after obtaining the electric energy parameters sent by the signal reading and recording module, the total error of the electric energy parameters is verified according to the error compensation amount of the current temperature zone interval inside the electric energy meter, thereby obtaining the interval error debugging value; The polynomial error calculation module is applied to the scenario where the electric energy parameter is nonlinearly significant, and the polynomial fitting of the full temperature range error inside the electric energy meter is performed through the sub-item dynamic compensation module, so as to obtain the fitting error debugging value; The sub-item dynamic compensation module is used to obtain the interval error debugging value or the fitting error debugging value, and then perform subsequent temperature compensation according to the corresponding error debugging value.

2. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 1 is characterized in that: The specific analysis process of the interval error debugging value is as follows: S11. Read the linear compensation coefficient of the electric energy meter in each temperature zone from the existing database, including the temperature sensitivity coefficient and the reference offset ; S12, set the temperature parameter to K, the temperature interval separation point is , , ; S13. Substitute the error compensation coefficient into the following formula to calculate the total error under the temperature parameter K: ; In the formula, Expressed as the total error at temperature T, is the minimum value of the operating temperature range, is the maximum value of the operating temperature range; S14, after calculation, It is set as the interval error debugging value and output to the sub-item dynamic compensation module.

3. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 1 is characterized in that: The specific analysis process of the fitting error debugging value is as follows: S21, obtain the reference error of the electric energy meter at zero temperature and zero current, and set it as ; S22. Obtain the coefficients of temperature-related items from the existing database, including the linear temperature item coefficients , Secondary temperature term coefficient , cubic temperature coefficient , Linear current term coefficient and the current cross-term coefficient ; S23, substituting the reference error obtained in S21 and the coefficient of the temperature-related term obtained in S22 into the following formula to obtain the fitting error debugging value: ； In the formula, K is the current temperature parameter, and I is the load current; S24, after calculation, It is set as the fitting error debugging value and output to the sub-item dynamic compensation module.

4. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 3 is characterized in that: A lag error elimination module is also provided between the sub-item dynamic compensation module and the polynomial error calculation module. The lag error elimination module obtains the temperature rise and fall rate inside the electric energy meter and determines the dynamic compensation value, and then obtains the quadratic fitting error debugging value based on the dynamic compensation value analysis. Finally, the obtained quadratic fitting error debugging value eliminates the lag effect caused by the rapid temperature change in the process of obtaining the fitting error debugging value by the polynomial error calculation module.

5. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 4 is characterized in that: The steps of the hysteresis error elimination module to obtain the dynamic compensation value are as follows: S31, calculating the current internal temperature rise and fall rate of the electric energy meter according to the temperature data monitored inside the electric energy meter; S32, substituting the internal temperature increase rate of the electric energy meter into the following formula for dynamic compensation to obtain a dynamic compensation value: ； In the above formula, Indicates the dynamic compensation value; Indicates the rate of temperature change.

6. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 5, characterized in that: The steps of calculating the quadratic fitting error debugging value by the hysteresis error elimination module are as follows: S41, replace the original linear temperature term coefficient with the dynamic compensation value , Secondary temperature term coefficient , cubic temperature coefficient Substitute the calculation formula of the fitting error debugging value to obtain the compensated quadratic fitting error debugging value: ； S42, after calculation, It is set as the quadratic fitting error debugging value and output to the sub-item dynamic compensation module.

7. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 1, characterized in that: The signal reading and recording module includes a signal transmission unit, a ROM memory and a signal conditioning circuit. The signal transmission unit is used to obtain the monitoring data of the electric energy meter and upload it to the ROM memory for short-term storage after acquisition. The signal conditioning circuit is used to amplify and filter the noisy signal output by the signal transmission unit.

8. The temperature-compensated wide-temperature-range high-precision electric energy collection terminal according to claim 1, characterized in that: The sub-item dynamic compensation module is connected to the external data processing terminal signal, and the sub-item dynamic compensation module is used to send the debugging value obtained by the interval compensation error calculation module or the polynomial error calculation module to the external data processing terminal, and the external data processing terminal performs compensation adjustment of the power acquisition parameters.

9. A temperature-compensated wide temperature range high-precision electric energy meter, using the temperature-compensated wide temperature range high-precision electric energy acquisition terminal as described in any one of claims 1 to 8, characterized in that: include: The electric energy metering module is used to obtain the changes in current and voltage at the end to be detected and calculate the electric energy usage; Wide temperature power supply module, used for power supply during measurement in a wide temperature range; A multi-point temperature sensor is arranged at a local position of the PCB and is used for checking the temperature at a local position of the PCB, wherein the local position of the PCB includes a metering chip position, a current sampling resistor position, and a voltage divider network position; The display module is used to display the specific parameters obtained by the electric energy metering module and the multi-point temperature sensor.

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