The invention discloses a device and method for measuring the electrical strength of material under the stress condition. The device comprises an insulating
oil tank used for encapsulating a sample to be tested, test electrodes, an electrical
strength testing device and a stress generation
system, wherein the test electrodes are arranged at the two sides of the sample to be tested and are connected with the electrical
strength testing device by
electrode leads; and the stress generation
system comprises a clamping device used for clamping the sample to be tested. The method for measuring the electrical strength of the material under the stress condition comprises the following steps of: firstly encapsulating the sample in the insulating
oil tank, and installing the test electrodes; then, leading the sample to be clamped on the stress generation
system and connected with the electrical
strength testing device, and fully filling insulating oil; starting the stress generation system for providing a load; after that, starting the electrical strength testing device, and recording the
voltage values of the tested sample which is broken down along with the rise of output
voltage; and finally, obtaining the electrical strength of the sample. The
measurement device is simple in structure and convenient in
assembly and operation, the test method is simple and convenient, the test cost is lower, and test results is accurate.